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HbA1c

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• Effect of vitamin E intake on glycemic control and insulin resistance in diabetic patients: an updated systematic review and meta-analysis of randomized controlled trials - Nutr J 2023 Feb 17 - "This indicates a significant lowering effect of vitamin E on HbA1c, fasting insulin and HOMA-IR, while no significant effect on fasting blood glucose in diabetic patients. However, in subgroup analyses, we found that vitamin E intake significantly reduced fasting blood glucose in studies with an intervention duration of < 10 weeks. In conclusion, vitamin E intake has a beneficial role in improving HbA1c and insulin resistance in a population with diabetes. Moreover, short-term interventions with vitamin E have resulted in lower fasting blood glucose in these patients" - See vitamin E at Amazon.com.
• Low-Dose Empagliflozin as Adjunct to Hybrid Closed-Loop Insulin Therapy in Adults With Suboptimally Controlled Type 1 Diabetes: A Randomized Crossover Controlled Trial - Diabetes Care 2022 Nov 4 - "Empagliflozin at 2.5 and 5 mg increased time in range during hybrid closed-loop therapy by 11-13 percentage points compared with placebo in those who otherwise were unable to attain glycemic targets. Future studies are required to assess long-term efficacy and safety" - See empagliflozin inhousepharmacy.vu.
• The effects of oral magnesium supplementation on glycemic control in patients with type 2 diabetes: A systematic review and dose-response meta-analysis of controlled clinical trials - Br J Nutr 2022 Jan 20 - "The dose-response testing indicated that the estimated mean difference in HbA1c at 500 mg/day was -0.73% (95% CI: -1.25, -0.22) suggesting modest improvement in HbA1c with strong evidence [P value: 0.004]. And in FBS at 360 mg/day was -7.11 mg/dL (95% CI: -14.03, -0.19) suggesting minimal amelioration in FBS with weak evidence [P value: 0.092] against the model hypothesis at this sample size. The estimated mean difference in FBS and HbA1c at 24 weeks was -15.58 mg/dL (95%CI: -24.67, -6.49) and -0.48 (95%CI: -0.77, -0.19) respectively, suggesting modest improvement in FBS [P value: 0.034] and HbA1c [P value: 0.001] with strong evidence against the model hypothesis at this sample size" - See magnesium supplements at Amazon.com.
• Effects of 12-Week Ingestion of Yogurt Containing Lactobacillus plantarum OLL2712 on Glucose Metabolism and Chronic Inflammation in Prediabetic Adults: A Randomized Placebo-Controlled Trial - Nutrients. 2020 Jan 31 - "The ingestion of Lactobacillus plantarum OLL2712 (OLL2712) cells improved glucose metabolism by suppressing chronic inflammation in mouse models and in a preliminary clinical study. We aimed to clarify the effect of OLL2712 on glucose metabolism and chronic inflammation for healthy adults. Prediabetic adults (n = 130, age range: 20-64 years) were randomly assigned to either the placebo or OLL2712 groups (n = 65 each) and were administered conventional yogurt or yogurt containing more than 5 × 109 heat-treated OLL2712 cells, respectively, daily for 12 weeks. Reduced HbA1c levels after 12 weeks of treatment were observed in both groups compared to those at baseline; however, the 12-week reduction of HbA1c levels was significantly greater in the OLL2712 group than in the placebo group. Increased chronic inflammation marker levels and insulin-resistant index (HOMA-IR) occurred in the placebo group but not in the OLL2712 group. Fasting blood glucose (FBG) levels did not change significantly in both groups; however, in subgroup analyses including participants with higher FBG levels, FBG levels were significantly reduced only in the OLL2712 group compared to baseline. These results suggest that OLL2712 cell ingestion can reduce HbA1c levels and can prevent the aggravation of chronic inflammation and insulin resistance" - [Nutra USA]
• Increased Levels of Glycated Hemoglobin A1c and Iron Deficiency Anemia: A Review - Med Sci Monit. 2019 Nov 7;25:8371-8378 - "Studies have shown that iron deficiency anemia (IDA) is associated with increased levels of glycated hemoglobin A1c (HbA1c), but the mechanism remains unclear. Hematological changes, iron metabolism, study methodology, and other factors could affect the results of diagnostic investigations, leading to false results. Red blood cell turnover in the bone marrow and the quality and heterogeneity of erythrocytes may influence the rate of hemoglobin glycation. By changing the structure of hemoglobin and inducing peroxidation, iron deficiency accelerates glycation" - See iron supplements at Amazon.com.
• The use of probiotic L. fermentum ME-3 containing Reg'Activ Cholesterol supplement for 4 weeks has a positive influence on blood lipoprotein profiles and inflammatory cytokines: an open-label preliminary study - Nutr J. 2016 Oct 28;15(1):93 - "Reg'Activ Cholesterol (RAC) ... Forty-five clinically asymptomatic participants consumed an RAC containing an antioxidative and antiatherogenic probiotic Lactobacillus fermentum ME-3 (LFME-3) for 4 weeks ... The reduction of total cholesterol (from 6.5 ± 1.0 to 5.7 ± 0.9 mmol/l, p = 9.90806E-11) was on the account of LDL cholesterol as the HDL cholesterol level rose from 1.60 ± 0.31to 1.67 ± 0.34mml/l, p = 0.01. HbA1c% was reduced from 5.85 ± 0.28 to 5.66 ± 0.25 p = 4.64E-05 and oxLDL decreased from 84 ± 20 to 71 ± 15 U/l" - See Reg'Activ Cholesterol at Amazon.com.
• Beneficial effects of oral chromium picolinate supplementation on glycemic control in patients with type 2 diabetes: A randomized clinical study - J Trace Elem Med Biol. 2015 Oct - "A four month controlled, single blind, randomized trial was performed with 71 patients with poorly controlled (hemoglobin A1c [HbA1c]>7%) T2DM divided into 2 groups: Control (n=39, using placebo), and supplemented (n=32, using 600μg/day CrPic) ... CrPic supplementation significantly reduced the fasting glucose concentration (-31.0mg/dL supplemented group; -14.0mg/dL control group; p<0.05, post- vs. pre-treatment, in each group) and postprandial glucose concentration (-37.0mg/dL in the supplemented group; -11.5 mg/dL in the control group; p<0.05). HbA1c values were also significantly reduced in both groups (p<0.001, comparing post- vs. pre-treatment groups). Post-treatment HbA1c values in supplemented patients were significantly lower than those of control patients. HbA1c lowering in the supplemented group (-1.90), and in the control group (-1.00), was also significant, comparing pre- and post-treatment values, for each group (p<0.001 and p<0.05, respectively) ... HDL-c and LDL-c were significantly lowered, comparing pre- and post-treatment period, in the control group" - [Nutra USA] - See chromium supplements at Amazon.com.
• Impact of daily supplementation of Spirulina platensis on the immune system of naïve HIV-1 patients in Cameroon: a 12-months single blind, randomized, multicenter trial - Nutr J. 2015 Jul 21 - "The significant increase of CD4 count cells (596.32-614.92 cells count) and significant decrease of viral load levels (74.7 × 103-30.87 × 103 copies/mL) of the patients who received a supplementation of S. platensis was found after 6 months of treatment. Haemoglobin level was also significantly higher in the same group while the fasting blood glucose concentration decreased after 12 months compared to control" - See spirulina at Amazon.com.
• Effects of Resveratrol on Memory Performance, Hippocampal Functional Connectivity, and Glucose Metabolism in Healthy Older Adults - J Neurosci. 2014 Jun 4;34(23):7862-7870 - "Twenty-three healthy overweight older individuals that successfully completed 26 weeks of resveratrol intake (200 mg/d) were pairwise matched to 23 participants that received placebo ... functional connectivity (FC) ... We observed a significant effect of resveratrol on retention of words over 30 min compared with placebo (p = 0.038). In addition, resveratrol led to significant increases in hippocampal FC, decreases in glycated hemoglobin (HbA1c) and body fat, and increases in leptin compared with placebo (all p < 0.05). Increases in FC between the left posterior hippocampus and the medial prefrontal cortex correlated with increases in retention scores and with decreases in HbA1c" - See resveratrol products at Amazon.com.
• Effect of resveratrol on glucose control and insulin sensitivity: a meta-analysis of 11 randomized controlled trials - Am J Clin Nutr. 2014 Apr 2 - "a strategic literature search of PubMed, Embase, MEDLINE, and the Cochrane Library (updated to March 2014) for randomized controlled trials ... Resveratrol consumption significantly reduced fasting glucose, insulin, hemoglobin A1c, and insulin resistance (measured by using the homeostatic model assessment) levels in participants with diabetes. No significant effect of resveratrol on glycemic measures of nondiabetic participants was found in the meta-analysis" - See resveratrol products at Amazon.com.
• Vitamin D deficiency among the elderly: insights from Qatar - Curr Med Res Opin. 2014 Mar 13 - "A high prevalence of VitD deficiency (72%) was observed among the elderly in Qatar. Lower VitD was associated with higher HbA1c and lower HDL-C levels" - See vitamin D at Amazon.com.
• Effect of fenugreek (Trigonella foenum-graecum L.) intake on glycemia: a meta-analysis of clinical trials - Nutr J. 2014 Jan 18;13(1):7 - "A total of 10 trials were identified. Fenugreek significantly changed fasting blood glucose by -0.96 mmol/l (95% CI: -1.52, -0.40; I2 = 80%; 10 trials), 2 hour postload glucose by -2.19 mmol/l (95% CI: -3.19, -1.19; I2 = 71%; 7 trials) and HbA1c by -0.85% (95% CI -1.49%, -0.22%; I2 = 0%; 3 trials) as compared with control interventions" - See fenugreek at Amazon.com.
• Long-term effect of dietary fibre intake on glycosylated haemoglobin A1c level and glycaemic control status among Chinese patients with type 2 diabetes mellitus - Public Health Nutr. 2013 Jul 24:1-7 - "Two cross-sectional surveys were conducted in 2006 and 2011, with the second one being a repeat survey on a sub-sample from the initial one ... Dietary intake was assessed with a validated FFQ ... dietary fibre intake at the first survey was inversely associated with uncontrolled glycaemic status at the second survey, with adjusted odds ratios across the tertiles of intake being 1.00, 0.72 (95 % CI 0.43, 1.21) and 0.58 (95 % CI 0.34, 0.99; P trend = 0.048) ... Dietary fibre may have a long-term beneficial effect on HbA1c level among Chinese diabetes patients" - See Garden of Life, RAW Fiber, Beyond Organic Fiber at iHerb.
• Effect of green tea on glucose control and insulin sensitivity: a meta-analysis of 17 randomized controlled trials - Am J Clin Nutr. 2013 Jun 26 - "Seventeen trials comprising a total of 1133 subjects were included in the current meta-analysis. Green tea consumption significantly reduced the fasting glucose and hemoglobin A1c (Hb A1c) concentrations by -0.09 mmol/L (95% CI: -0.15, -0.03 mmol/L; P < 0.01) and -0.30% (95% CI: -0.37, -0.22%; P < 0.01), respectively. Further stratified analyses from high Jadad score studies showed that green tea significantly reduced fasting insulin concentrations (-1.16 μIU/mL; 95%CI: -1.91, -0.40 μIU/mL; P = 0.03)" - See green tea extract at Amazon.com.
• Vitamin C and A1c Relationship in the National Health and Nutrition Examination Survey (NHANES) 2003-2006 - J Am Coll Nutr. 2011 Dec;30(6):477-83 - "The consumption of foods high in vitamin C has been associated with lower risk of diabetes ... Vitamin C concentrations were inversely associated with A1c (p = 0.0202). Stronger inverse associations were observed in subjects 18-44 years of age (p = 0.0017), as well as in female (p = 0.0035) and Mexican American (p = 0.0149) subgroups. Evidence of a significant interaction between vitamin C and vitamin D was noted in subjects aged 18-44 years and in females (p = 0.0073 and 0.0095 respectively), with the inverse association tending to be evident at lower levels of vitamin D"
• Creatine in Type 2 Diabetes - Medscape, 5/10/11 - &"The patients were allocated to receive either creatine (CR) (5 g.d−1) or placebo (PL) ...This is the first randomized controlled trial to describe the beneficial effects of creatine supplementation on glycemic control in type 2 diabetic patients who underwent exercise training. As such, this supplement emerges as a valuable nonpharmacological approach for treating diabetes ... the mean reduction in HbA1c (−1.1%) was superior to that commonly seen with exercise training[25] or metformin[10] treatment alone, pointing out the therapeutic potential of this novel nutritional intervention" - See creatine at Amazon.com
• Effects of aerobic and resistance training on hemoglobin A1c levels in patients with type 2 diabetes: a randomized controlled trial - JAMA. 2010 Nov 24;304(20):2253-62 - "The mean changes in HbA(1c) were not statistically significant in either the resistance training (-0.16%; 95% CI, -0.46% to 0.15%; P = .32) or the aerobic (-0.24%; 95% CI, -0.55% to 0.07%; P = .14) groups compared with the control group. Only the combination exercise group improved maximum oxygen consumption (mean, 1.0 mL/kg per min; 95% CI, 0.5-1.5, P < .05) compared with the control group. All exercise groups reduced waist circumference from -1.9 to -2.8 cm compared with the control group. The resistance training group lost a mean of -1.4 kg fat mass (95% CI, -2.0 to -0.7 kg; P < .05) and combination training group lost a mean of -1.7 (-2.3 to -1.1 kg; P < .05) compared with the control group ... Among patients with type 2 diabetes mellitus, a combination of aerobic and resistance training compared with the nonexercise control group improved HbA(1c) levels. This was not achieved by aerobic or resistance training alone"
• Can the Mediterranean diet lower HbA1c in type 2 diabetes? Results from a randomized cross-over study - Nutr Metab Cardiovasc Dis. 2010 Jul 29 - "Compared with usual diet, on the ad libitum Mediterranean intervention diet glycosylated haemoglobin fell from 7.1% (95% CI: 6.5-7.7) to 6.8%"
• Poor control of diabetes may be linked to low vitamin D - Science Daily, 6/21/10 - "Despite receiving regular primary care visits before referral to the endocrine clinic, 91 percent of patients had either vitamin D deficiency (defined as a level below 15 nanograms per deciliter, or ng/dL) or insufficiency (15 to 31 ng/dL) ... Additionally, the investigators found an inverse relationship between the patients' blood levels of vitamin D and their hemoglobin A1c value, a measure of blood sugar control over the past several months. Lower vitamin D levels were discovered in patients with higher average blood sugars as measured by HbA1c" - See vitamin D at Amazon.com.
• Effect of Oral Acetyl L-Carnitine Arginate on Biomarkers in Pre-Diabetics - Medscape, 10/28/09 - "3 g.day−1 of ALCA (n = 14; 31 +/- 3 yrs) or placebo (n = 15; 35 +/- 3 yrs) in a double-blind design, to consume for eight weeks ... slight improvements in glucose (109 +/- 5 to 103 +/- 5 mg.dL−1), HbA1c (6.6 +/- 1.1 to 6.2 +/- 1.2%), and HOMA-IR (3.3 +/- 1.3 to 2.9 +/- 1.2) ... slight improvement in glucose metabolism, as evidenced by minor decreases in blood glucose, insulin, and HbA1c (which may have been more pronounced with longer treatment, as HbA1c has a half-life equal to approximately 12 weeks" - See propionyl-l-carnitine products at Amazon.com.
• Low Glycemic Diets Help Diabetics Control Blood Sugar, Review Suggests - Science Daily, 1/2/0/09 - "Clinicians measured hemoglobin A1c levels, which give a picture of a person's blood glucose control over several weeks or months. The reviewers found that levels decreased by 0.5 percent with a low GI diet, noting that the findings were significant, both statistically and clinically"
• Fructose consumption and consequences for glycation, plasma triacylglycerol, and body weight: meta-analyses and meta-regression models of intervention studies - Am J Clin Nutr. 2008 Nov;88(5):1419-37 - "The meta-analysis shows that fructose intakes from 0 to >or=90 g/d have a beneficial effect on HbA(1c). Significant effects on postprandial triacylglycerols are not evident unless >50 g fructose/d is consumed, and no significant effects are seen for fasting triacylglycerol or body weight with intakes of <or=100 g fructose/d in adults" - I don't get it.  It would seem like fructose would make HbA(1c) worse.
• Effects of niacin on glucose control in patients with dyslipidemia - Mayo Clin Proc. 2008 Apr;83(4):470-8 - "the effects of niacin (</=2.5 g/d), alone or in combination with statins, on fasting glucose (an increase of 4%-5%) and hemoglobin A1c levels (an increase of </=0.3%) are modest, transient or reversible, and typically amenable to adjustments in oral hypoglycemic regimens without discontinuing niacin. Niacin therapy was infrequently associated with incident diabetes or the need for new insulin prescriptions. Studies showed important clinical benefits of niacin or niacin-statin regimens despite modest effects on glucose control. On a population basis, significant reductions in incidences of cardiovascular events and the degree of atherosclerotic progression associated with long-term niacin (or niacin-statin) therapy in patients with diabetic dyslipidemia outweigh the typically mild effects of this therapy on glycemic regulation"
• Randomized controlled trial for an effect of green tea-extract powder supplementation on glucose abnormalities - Eur J Clin Nutr. 2007 Jun 6 - "consumed a packet of green tea-extract powder containing 544 mg polyphenols (456 mg catechins) daily ... A significant reduction in hemoglobin A1c level and a borderline significant reduction in diastolic blood pressure were associated with the intervention" - See Jarrow green tea at iHerb.
• Study Results Show Diachrome(R) Improves Poorly-Controlled Blood Sugar Levels for People on Antidiabetic Prescription Medications - Doctor's Guide, 9/13/05 - "Study participants taking Diachrome with one or more antidiabetic medications saw an average range of 0.7 - 1.9% point reduction in HbA1c levels. The study also showed that insulin resistance was significantly reduced (P<0.05) in those taking thiazolidinediones and Diachrome ... Diachrome is a nutritional supplement specifically formulated for people with diabetes. It contains 600 mcg of chromium as Chromax(R) chromium picolinate and 2 mg of biotin" - See chromium supplements at Amazon.com and biotin at iHerb.
• The effect of the ingestion of Ginkgo biloba extract (EGb 761) on the pharmacokinetics of metformin in non-diabetic and type 2 diabetic subjects-A double blind placebo-controlled, crossover study - Clin Nutr. 2006 May 12 - "Ingestion of EGb 761 produced no significant changes in diagnostic laboratory tests in either group, except reducing glycosylated hemoglobin A(1c) levels (from 7.7+/-1.2 to 7.2+/-0.9%, P<0.05) in T2DM the subjects"
• Supplemental Chromium Picolinate and Biotin Appear to Decrease Blood Glucose and Lipid Levels in Type 2 Diabetics: Presented at ADA - Doctor's Guide, 6/17/05 - "Our most important finding is that chromium picolinate and biotin help to decrease hemoglobin A1c [HbA1c] values in poorly controlled diabetics ... 600 mcg chromium picolinate and biotin 2 mg/per day" - See biotin at Amazon.com.
• Uses of Metformin May Extend Beyond Patients with Type 2 Diabetes - Doctor's Guide, 9/4/03 - "In type 2 diabetics, metformin appears to decrease plasma fasting glucose and HbA1c levels without causing weight gain. Metformin may also have a positive influence on a variety of cardiovascular risk factors and may be useful in preventing diabetes in overweight individuals with mild hyperglycaemia ... while further study is necessary before more widespread use is encouraged, the role of metformin may be expanded for glucose control in children and teenagers with type 2 diabetes, in non-diabetic women with PCOS, and to prevent progression to diabetes"
• Chromium Supplements Appear to Improve Glucose Sensitivity in Diabetics - Medscape, 8/29/03 - "We think that chromium picolinate can influence a person's diabetic treatment so that levels of insulin required may be reduced ... HbA1c levels decreased from 9.5% to 9% during a six-month period in patients receiving a higher dose of the supplement, a difference that was statistically significant ... The study also showed a significant reduction in cholesterol levels and trends for improvement in triglycerides in both chromium picolinate groups as well as a reduction in blood pressure in all groups" - See iHerb or Vitacost chromium products.

Other News:

• Association between hemoglobin A 1c and asymptomatic carotid intima-media thickness in middle-aged and elderly populations without diabetes - Nutr Metab Cardiovasc Dis 2022 Feb 18 - "Carotid atherosclerosis, including carotid artery intima-media thickness, plaques, and stenosis, is an important risk factor for stroke. However, the association between hemoglobin A1c (HbA1c) and carotid intima-media thickness (cIMT) was inconsistent ... In this large-scale and cross-sectional study, high-normal HbA1c was associated with the risk of increased asymptomatic cIMT in a rural Chinese population without diabetes, especially in individuals aged <60 years"
• What are ideal blood sugar levels for preventing repeat strokes, heart attacks? - Science Daily, 9/29/21 - "After adjusting for factors like age and sex, researchers found that people's risk for a heart attack or similar vascular diseases was 27% greater when they were admitted to the hospital with A1C levels above 7.0%, compared to those admitted with A1C levels below 6.5%. People's risk for having another stroke was 28% greater when admitted to the hospital with A1C levels above 7.0%, compared to those below 6.5%"
• Evaluation of the effects of glycated hemoglobin on cardiac function in patients with short-duration type 2 diabetes mellitus: a cardiovascular magnetic resonance study - Diabetes Res Clin Pract 2021 Jul 14 - "Poor blood glucose control is an independent predictor of LV myocardial dysfunction for patients with short-term T2DM"
• Hemoglobin A1c-levels and subsequent risk of depression in individuals with and without diabetes - J Diabetes Complications 2021 May 12 - "In a population without baseline diabetes, higher HbA1c levels seemed associated with higher depression risk in women, whereas a U-shaped association was found in patients with known diabetes"
• Prediabetes may be linked to worse brain health - Science Daily, 2/11/21 - "people with higher than normal blood sugar levels were 42% more likely to experience cognitive decline over an average of four years, and were 54% more likely to develop vascular dementia over an average of eight years (although absolute rates of both cognitive decline and dementia were low) ... Participants were divided into five groups on the basis of the results -- "low-normal" level of blood sugar, normoglycaemia (having a normal concentration of sugar in the blood), prediabetes, undiagnosed diabetes and diabetes. A result between 42-48 mmol/mol (6.0-6.5%) was classified as prediabetes ... Though absolute rates of cognitive decline were low, people with prediabetes and diabetes had a similarly higher likelihood of cognitive decline -- 42% and 39% respectively ... Among 35,418 participants of the UK Biobank study who underwent MRI brain scans, researchers found that prediabetes was associated somewhat with a smaller hippocampus and more strongly associated with having lesions on the brain (white matter hyperintensities, WMHs) -- both associated with age-related cognitive impairment"
• HbA1c Levels in Diabetes Linked to Cognitive Decline - Medscape, 1/30/18 - "HbA1c has gained ground in the diagnosis and management of diabetes, showing greater reliability in predicting diabetes and indicating average circulating glucose levels over the prior 2 to 3 months ... each 1 mmol/mol increment in HbA1c was associated with an increased rate of decline in global cognitive z scores (–0.0009 SD/year), memory z scores (–0.0005 SD/year), and executive function z scores (–0.0008 SD/year). ... In terms of possible underlying mechanisms of the link between diabetes and cognitive decline, some evidence points to glycemic fluctuation as having a stronger effect on cognitive decline compared with sustained hyperglycemia, possibly through effects on endothelial function and induction of oxidative stress ... In addition, diabetes has been linked to subsequent cognitive impairment through direct mechanisms, such as inducing amyloid accumulation, and indirect mechanisms, including increasing microvascular disease of the central nervous system, thereby potentially playing a key role in vascular dementia, the authors note"
• Low Hemoglobin A1c Increases the Risk of Disability in Community-dwelling Older Non-diabetics Adults - J Nutr Health Aging. 2016;20(3):341-6 - "Lower level of HbA1c was associated with less frequent hypertension and less frequent use of aspirin or statin, and lower values of body mass index, hematocrit, total iron-binding capacity, albumin, and cholesterol level. The participants were categorized into 3 groups according to their HbA1c (group I, < 5.5%; group II, 5.5~5.9%; and group III, 6.0 ~ 6.4%). Although, there was no significant difference in functional status according to baseline HbA1c level, disability was more frequently observed as the HbA1c level decrease (18.3% in group I, 12.5% in group II, and 5.3% in group III, p=0.029) at the 5-year follow-up evaluation ... There was no significant difference in mortality among the groups, however, group I had a 2.071-fold higher risk for the incident disability or mortality over group III after adjusting age, gender, and possible confounder"
• High hemoglobin A1c levels within the non-diabetic range are associated with the risk of all cancers - Int J Cancer. 2015 Nov 6 - "Compared to individuals without known diabetes and HbA1c levels of 5.0-5.4%, the HRs for all cancers were 1.27 (95% confidence interval, 1.07-1.52); 1.01 (0.90-1.14); 1.28 (1.09-1.49); and 1.43 (1.14-1.80) for individuals without known diabetes and HbA1c levels <5.0%, 5.5-5.9%, 6.0-6.4%, and ≥6.5%, respectively, and 1.22 (1.02-1.47) for individuals with known diabetes. The lowest HbA1c group had the highest risk of liver cancer, and HbA1c levels were linearly associated with the risk of all cancers after excluding liver cancer ... our findings corroborate the notion that glycemic control in individuals with high HbA1c levels may be important not only to prevent diabetes but also to prevent cancer"
• Diabetes in midlife linked to significant cognitive decline 20 years later - Science Daily, 12/1/14 - "diabetes appears to age the mind roughly five years faster beyond the normal effects of aging. For example, on average, a 60-year-old with diabetes experiences cognitive decline on par with a healthy 65-year-old aging normally ... to have a healthy brain when you're 70, you need to eat right and exercise when you're 50 ... There is a substantial cognitive decline associated with diabetes, pre-diabetes and poor glucose control in people with diabetes" - Note:  It raises the question whether the lower the better for HBA1C or whether there's a U-curve.
• Hemoglobin A1c, comorbid conditions and all-cause mortality in older patients with diabetes: A retrospective 9-year cohort study - Diabetes Res Clin Pract. 2014 Jul 29 - "In our patient population, HbA1c scores<6.4% have significantly higher all-cause mortality"
• Glycosylated Hemoglobin Level Is Associated with Hearing Impairment in Older Japanese: The Kurabuchi Study - J Am Geriatr Soc. 2014 Jul 8 - "HbA1c levels were positively associated with hearing impairment (OR per 1.0% increase in HbA1c = 1.30, 95% CI = 1.00-1.68). This association persisted even after excluding 58 participants with a self-reported history of diagnosed diabetes mellitus. Longitudinal analysis revealed the temporality of the discussed association (OR = 1.52, 95% CI = 1.03-2.23)"
• Hemoglobin a1c in nondiabetic patients: an independent predictor of coronary artery disease and its severity - Mayo Clin Proc. 2014 Jul;89(7):908-16 - "compared with patients with HbA1c levels less than 5.5%, the odds ratios of occurrence of CAD in the HbA1c quartiles of 5.5% to 5.7%, 5.8% to 6.1%, and greater than 6.1% were 1.8 (95% CI, 1.2-2.7), 3.5 (95% CI, 2.3-5.3), and 4.9 (95% CI, 3.0-8.1), respectively" - See metformin at The Antiaging Store.
• Hemoglobin A1c and Cardiovascular Risk - Medscape, 6/24/14 - "An approximately J-shaped association was found between A1c and CVD risk (approximate 20% increased risk at < 4.5% and beginning at ≥5.5%, relative to the reference category of 5.0%-5.5%)"
• Stroke Risk Increases With HbA1c Level in Women but Not Men - Medscape, 3/3/14 - "Among women, those with HbA 1c of 8.0%–8.9% were 19% more likely to have a stroke than those with normal blood sugar levels; those with levels of 9.0%–9.9% had a 32% increased risk for stroke; and those with HbA 1c above 10% a 42% higher risk ( P for trend < .001). Men demonstrated a trend toward increased risk for stroke as HbA 1c increased, but this was not statistically significant"

• HbA1c and Heart Failure Risk among Diabetic Patients - J Clin Endocrinol Metab. 2013 Dec 2 - "prospectively investigated the race-specific association of different levels of HbA1c at baseline and during an average of 6.5 years of follow-up with incident HF risk among 17,181 African American and 12,446 White diabetic patients within the Louisiana State University (LSU) Hospital System ... The multivariable-adjusted hazard ratios (HRs) of HF associated with different levels of HbA1c at baseline (<6.0% [reference group], 6.0-6.9%, 7.0-7.9%, 8.0-8.9%, 9.0-9.9%, and ≥10.0%,) were 1.00, 1.02 (95% confidence interval [CI] 0.91-1.15), 1.21 (1.05-1.38), 1.29 (1.12-1.50), 1.37 (1.17-1.61), and 1.49 (1.31-1.69) (P trend <0.001) for African American diabetic patients, and 1.00, 1.09 (0.96-1.22), 1.09 (0.95-1.26), 1.43 (1.22-1.67), 1.49 (1.25-1.77), and 1.61 (1.38-1.87) (P trend <0.001) for white diabetic patients, respectively"

  HbA1c	African American	White
  <6.0%	1.00	1.00
  6.0-6.9%	1.02	1.09
  7.0-7.9%	1.21	1.09
  8.0-8.9%	1.29	1.43
  9.0-9.9%	1.37	1.49
  ≥10.0%	1.49	1.61

• Glucose Levels Linked to Dementia - Medscape, 11/14/13 - "This elegantly conducted study demonstrated that an increased risk for dementia was associated with higher glucose levels in populations with and without diabetes"
• Hemoglobin A1C in non-diabetic patients: An independent predictor of coronary artery disease and its severity - Diabetes Res Clin Pract. 2013 Oct 9 - "We enrolled 299 consecutive individuals undergoing coronary angiography for suspected ischemia. Patients were included if they had no history of prior revascularization or diabetes mellitus and had fasting blood glucose<126mg/dl (7.0mmol/l) and HbA1c<6.5% (47mmol/mol). The severity of the CAD was also evaluated using the Gensini score ... With increasing HbA1c levels, there was a significant increase in the prevalence of CAD and number of vessels involved. In multivariate analysis, HbA1c emerged as an independent predictor of significant CAD (OR: 2.8, 95% CI: 1.3-6.2, p=0.009). Adjusted ORs for the occurrence of CAD were highest in subjects with both hsCRP and HbA1c in the upper 2 quartiles (OR: 4.183; 95% CI: 1.883-9.290, p<0.0001). There was a significant association between Gensini score and increasing HbA1c tertiles (p=0.038). The ideal cut-off value of HbA1c for prediction of the occurrence of CAD was 5.6% 38mmol/mol)"
• High Glucose Linked to Poorer Memory, Even Without Diabetes - Medscape, 10/23/13 - "lowering blood glucose levels, possibly even to relatively low levels, might help preserve cognition ... Strategies that help lower blood glucose levels include a healthy Mediterranean-type diet and regular physical activity ... cross-sectional study included 141 healthy persons (mean age, 63.1 years) ... lower performance on 3 memory tasks (delayed recall, learning ability, and consolidation) was associated with higher levels of both the long-term marker of glucose control (HbA1c) and the short-term glucose marker ... For insulin, there was a "general trend going in the same direction" but correlations were less clear, and without the same direct relationship ... How low is it safe to go in terms of blood glucose levels? ... If you're used to low blood sugar levels, you can go quite low ... The idea is that the lower the A1c the better your brain function" - [Science Daily]
• Glycemic Control and Risk of Cardiovascular Disease Hospitalization and All-Cause Mortality - J Am Coll Cardiol. 2013 May - "Compared with patients with mean A1C 7.0%-7.4%, those with mean A1C <6.0% had a 75% increased risk of CVD hospitalization (hazard ratio [HR] 1.68, 95% CI 1.39-2.04, p<0.001) after adjustment for demographic and clinical characteristics. Those with A1C 6.0%-6.4% (1.18, 1.00-1.40, p=0.048) and 6.5%-6.9% (1.18, 1.02-1.37, p=0.031) also had significantly higher risk relative to the reference group of 7.0%-7.4%, as did patients with A1C 8.5%-8.9% (HR 1.55, 1.24-1.94, p<0.001) and >9.0% (HR 1.83, 1.50-2.22, p<0.001). Risk of all-cause mortality was significantly greater than the reference group among A1C categories <6.0%, 6.0%-6.4%, 6.5%-6.9%, and >9.0% ... The relationship between mean A1C and CVD hospitalizations and all-cause mortality is U-shaped, with greater risk at both higher and lower A1C levels"
• Insulin sensitivity, and β-cell function in relation to hemoglobin A1C - Nutr Metab Cardiovasc Dis. 2013 Apr 16 - "As A1C increased to ≥5.7%, a sharp decrease in insulin sensitivity and β-cell function, measured as disposition index, was observed ... Caucasian individuals with A1C ≥5.7% exhibit both core pathophysiological defects of type 2 diabetes i.e. insulin resistance and β-cell dysfunction"
• U-Shape Association Between Hemoglobin A1c and Late Mortality in Patients With Heart Failure After Cardiac Surgery - Am J Cardiol. 2013 Feb 4 - "Patients with and without New York Heart Association class III or IV heart failure were divided into quartiles according to the preoperative HbA1c level ... After adjusting for confounders, the patients without heart failure and with HbA1c ≤5.7% had the lowest risk of death. In patients with preoperative heart failure, we found a U-shaped association between HbA1c levels and late mortality, with those patients with HbA1c levels of 5.8% to 6.2% having the lowest risk of death. HbA1c levels ≤5.7% and ≥7.2% were associated with statistically significant greater risks of death"
• Glycated Hemoglobin is Associated with the Complexity of Coronary Artery Disease, Even in Non-Diabetic Adults - J Atheroscler Thromb. 2012 Aug 9 - "Glycated hemoglobin (HbA1c) is associated with an increased risk of cardiovascular disease and death from any cause. The aim of this study was to examine the relationship between HbA1c value and coronary artery lesion complexity ... The complexity of the coronary artery lesions was evaluated using the SYNTAX score (SXscore). The subjects were divided into quartiles according to either the HbA1c or the fasting plasma glucose (FPG) values ... Both the higher HbA1c quartiles (Q1 to Q4) and higher FPG quartiles were significantly associated with a higher SXscore ... HbA1c is significantly associated with the complexity of coronary lesions. This association is even observed in non-diabetic adults. A higher HbA1c value is an independent predictor of the prevalence of complex coronary lesions"
• Low Hemoglobin A1c in Nondiabetic Adults: An elevated risk state? - Diabetes Care. 2012 Aug 1 - "Compared with participants with HbA(1c) in the normal range (5.0 to <5.7%), participants with low HbA(1c) were younger, less likely to smoke, had lower BMI, lower white cell count and fibrinogen levels, and lower prevalence of hypercholesterolemia and history of coronary heart disease. However, this group was more likely to have anemia and had a higher mean corpuscular volume. In adjusted Cox models with HbA(1c) of 5.0 to <5.7% as the reference group, HbA(1c) <5.0% was associated with a significantly increased risk of all-cause mortality (hazard ratio [HR]: 1.32, 95% CI: 1.13-1.55) and of cancer death (1.47, 95% CI: 1.16-1.84). We also noted nonsignificant trends toward increased risk of death from cardiovascular causes (1.27; 95% CI, 0.93-1.75) and respiratory causes (1.42, 95% CI: 0.78-2.56). There was a J-shaped association between HbA(1c) and risk of liver disease hospitalization"
• Association of glycated hemoglobin with carotid intimal medial thickness in Asian Indians with normal glucose tolerance - J Diabetes Complications. 2012 Jul 11 - "To assess the association of glycated hemoglobin (HbA1c) levels with carotid intimal medial thickness (CIMT) in Asian Indians with normal glucose tolerance (NGT) ... The study group included 1383 NGT subjects, of whom 760 (54.9%) were women. The mean CIMT value in the 1st quartile of HbA1c (<5.2%) was 0.65 and it increased significantly to 0.73 in the last quartile of HbA1c (>5.8) (p<0.001). Regression analysis showed that HbA1c had a strong association with CIMT after adjusting for age, gender, waist circumference, systolic and diastolic blood pressure, LDL cholesterol, serum triglycerides, HOMA-IR and smoking (ß - 0.046, p=0.047) ... Even among subjects with NGT, there is a significant increase in CIMT with increasing levels of HbA1c, showing the value of using HbA1c for diagnosis of glucose intolerance"
• Relationship between HbA(1c) levels and risk of cardiovascular adverse outcomes and all-cause mortality in overweight and obese cardiovascular high-risk women and men with type 2 diabetes - Diabetologia. 2012 May 26 - "The median HbA(1c) concentration was 7.2% (3.8-15.9%) (55 mmol/l [18-150 mmol/l]) and median diabetes duration was 7 years (0-57 years). For each 1 percentage point HbA(1c) increase, the adjusted HR for the primary endpoint was 1.17 (95% CI 1.11, 1.23); no differential sex effect was observed (p = 0.12 for interaction). In contrast, the risk of all-cause mortality was found to be greater in women than in men: HR 1.22 (1.10, 1.34) vs 1.12 (1.04, 1.20) for each 1 percentage point HbA(1c) increase (p = 0.02 for interaction). There was no evidence of increased risk associated with HbA(1c) ≤6.4% (≤46 mmol/l). Glucose-lowering treatment regimens, diabetes duration or a history of cardiovascular disease did not modify the associations"
• Low Glycated Hemoglobin and Liver Disease in the U.S. Population - Diabetes Care. 2011 Sep 27 - "We observed J-shaped associations between HbA(1c) and liver enzymes and hepatic steatosis. In adjusted models, HbA(1c) <4.0% was strongly associated with elevated alanine aminotransferase (OR 3.62 [95% CI 1.09-12.02]) and aspartate aminotransferase (6.80 [2.99-15.43]).CONCLUSIONSLow HbA(1c) values were associated with liver enzymes and steatosis in the U.S. population. Liver disease may partially explain the association of HbA(1c) with mortality and other long-term outcomes"
• Registry Data Support 'J-Curve' CV Risk Theory for Hba1c in Diabetes - Medscape, 9/16/11 - "In Cox regression analyses that used age and systolic blood pressure as covariates, the hazard ratio for the composite end point was lowest for HbA1c levels in the range of 6% to 7%, but rose below 6% and above 7%"
• Association between HbA(1c) and cardiovascular disease mortality in older Hong Kong Chinese with diabetes - Diabet Med. 2011 Sep 14. - "A total of 2137 Chinese aged 65 years or above attending the Elderly Health Service, Department of Health, Hong Kong, with diagnosed diabetes had HbA(1c) measured during 1998 to 2000 and were followed up to 2009 ... After adjusting for potential confounders, higher HbA(1c) (≥ 69 mmol/mol, 8.5%) increased the risk of cardiovascular disease (hazard ratio 2.11;95% CI 1.37-3.25) and stroke mortality (hazard ratio 2.43; 95% CI 1.06-5.55) compared with HbA(1c) of 58-68 mmol/mol (7.5-8.4%), and increased the risk of all-cause (hazard ratio 1.41; 95% CI 1.06-1.86) and coronary heart disease mortality (hazard ratio 2.44; 95% CI 1.11-5.37) compared with HbA(1c) of 48 mmol/mol (6.5%) or less. Analysis of HbA(1c) as a continuous variable showed that every XX mmol/mol (1%) increase in HbA(1c) decreased stroke mortality risk by 51% in those with HbA(1c) level less than 48 mmol/mol (6.5%) and increased stroke mortality risk by 30% in those with an HbA(1c) level of 48 mmol/mol (6.5%) or higher, suggesting a U-shaped association between HbA(1c) and stroke mortality.  Conclusion: High HbA(1c) predicted excess risk of all-cause, cardiovascular disease, coronary heart disease and stroke mortality. The question of whether low HbA(1c) increases mortality in older patients with diabetes needs further investigation"
• Glycated Hemoglobin A1c, Fasting Plasma Glucose, and Two-Hour Postchallenge Plasma Glucose Levels in Relation to Carotid Intima-Media Thickness in Chinese with Normal Glucose Tolerance - J Clin Endocrinol Metab. 2011 Jun 29 - "carotid intima-media thickness (CIMT) ... participants in the highest quartile of HbA1c, as compared with those in the lowest quartile, still conferred a 68% increased odds of elevated CIMT (≥0.70 mm)"
• Optimal range of HbA1c for the prediction of future diabetes: A 4-year longitudinal study - Diabetes Res Clin Pract. 2011 Jun 13 - "The point showing a substantial difference in the Kaplan-Meier curves was a HbA1c of 5.7%. The incidence of diabetes was 20.8% among subjects with a baseline HbA1c of 5.7-6.4%. The hazard ratio of developing diabetes was 6.5 (95% CI, 3.7-10.2) in the subjects with a HbA1c of 5.7% compared with the bottom category of HbA1c (<5.0%)"
• Association between glycosylated haemoglobin A(1c) and endothelial function in an adult non-diabetic population - Atherosclerosis. 2011 Apr 16 - "Flow-mediated dilation (FMD) and nitrate-mediated dilation (NMD) measurements of the brachial artery were performed using standardised ultrasound techniques ... We conclude that higher serum HbA(1c) levels in non-diabetic subjects are inversely associated with FMD in women without antihypertensive medication, but not in men. The gender-specific aspects concerning the association of HbA(1c) levels and NMD in this population should be investigated in further studies. Our results support current considerations that subclinical disorders of glucose metabolism measured by serum HbA(1c) are associated with subclinical cardiovascular diseases detected by FMD, especially in women"
• Glycated Hemoglobin Predicts All-Cause, Cardiovascular, and Cancer Mortality in People Without a History of Diabetes Undergoing Coronary Angiography - Diabetes Care. 2011 Apr 22 - "The multivariable-adjusted hazard ratios (HR) (95% CI) for glycated hemoglobin values of <5.0, 5.0-5.4, 5.5-5.9, 6.0-6.4, 6.5-7.4, and ≥7.5% for all-cause mortality were 1.36 (0.85-2.18), 1.00 (0.76-1.32), 1.00 (reference), 1.11 (0.88-1.41), 1.39 (1.07-1.82), and 2.15 (1.32-3.53), respectively. Similar J-shaped relationships were found between glycated hemoglobin and cardiovascular and cancer mortality. The associations of glycated hemoglobin with all-cause and cardiovascular mortality remained significant after inclusion of fasting glucose as a covariate. However, fasting glucose was not significantly related to mortality when adjusting for glycated hemoglobin"
• Low Glycemic Level Linked to Higher Mortality in Elderly - Medscape, 4/21/11 - "There was a U-shaped association of mortality with A1c level. Compared with the mortality risk with A1c level of less than 6.0%, the risk was lower for A1c levels between 6.0% and 9.0% (eg, HR, 0.83 [95% CI, 0.76 - 0.90] for A1c levels 7.0% - 7.9%) and higher at A1c levels of 11.0% or more (HR, 1.31; 95% CI, 1.09 - 1.57). At A1c levels of 8.0% or higher, the risk was significantly higher for any endpoint (complication or death) ... We cannot say whether this unexpected finding is due to the very low blood sugar itself, the treatments used to control blood sugars, or to some other factors not directly related to the care of diabetes ... It may be that the sickest patients at high risk of dying simply had low blood sugars to start with, rather than anything directly associated with the care of diabetes increasing the risk of death"
• High-Normal HbA1c Is a Strong Predictor of Type 2 Diabetes in the General Population - Diabetes Care. 2011 Feb 9 - "We measured HbA(1c) in 919 Caucasian subjects, aged 40-79 years, and recorded new cases of type 2 diabetes in the following 15 years. Diabetes was diagnosed with HbA(1c). RESULTS Subjects were stratified according to baseline HbA(1c) (<5.0, 5.00-5.49 [reference], 5.50-5.99, and 6.00-6.49%). Sex- and age-adjusted hazard ratios (95% CI) for type 2 diabetes were 1.11 (0.30-4.41), 1.00, 3.79 (1.79-8.06), and 12.50 (5.51-28.34), respectively. Results did not change after adjusting for several putative confounding factors and were confirmed when models with updated variables were used. CONCLUSIONS HbA(1c) is an independent risk factor for type 2 diabetes. Subjects with high-normal levels of HbA(1c) deserve particular attention because they have a strong risk of developing diabetes"
• Influence of glycosylated hemoglobin on sight-threatening diabetic retinopathy: A population-based study - Diabetes Res Clin Pract. 2011 Feb 3 - "sight-threatening diabetic retinopathy (STDR) ... A statistically significant difference (p<0.05) was noted in the duration of diabetes, gender, body mass index, HbA1c, micro- and macro-albuminuria between both non-STDR and STDR groups as compared to the no-diabetic retinopathy (DR) group. On multivariate analysis, HbA1c (non-STDR: odd's ratio OR=1.23; 95% confidence interval CI=1.15-1.32; p<0.0001; STDR: OR=1.31 95% CI=1.14-1.52; p<0.0001) was found to be significantly associated with non-STDR and STDR when compared with the no-DR group. The Receiver Operating Characteristic analysis showed that the cut-off value of 8.0 had 75.6% sensitivity and 58.2% specificity with 64.9% maximum area under the curve ... HbA1c value >8.0% was significantly related with STDR. In a screening programme, the cut-off value of HbA1c >8.0% provided a maximum yield of STDR"
• Hemoglobin A1c as a Predictor of Incident Diabetes - Diabetes Care. 2011 Feb 2 - "These patients were tracked for 8 years for a subsequent diagnosis of diabetes. RESULTS During an average follow-up of 4.4 years, 3,329 (26.9%) developed diabetes. HbA(1c) ≥5.0% carried a significant risk for developing diabetes during follow-up. When compared with the reference group (HbA(1c) <4.5%), HbA(1c) increments of 0.5% between 5.0 and 6.4% had adjusted odds ratios of 1.70 (5.0-5.4%), 4.87 (5.5-5.9%), and 16.06 (6.0-6.4%) (P < 0.0001). Estimates of hazard ratios similarly showed significant increases for HbA(1c) ≥5.0%. A risk model for incident diabetes within 5 years was developed and validated using HbA(1c), age, BMI, and systolic blood pressure. CONCLUSIONS The incidence of diabetes progressively and significantly increased among patients with an HbA(1c) ≥5.0%, with substantially expanded risk for those with HbA(1c) 6.0-6.4%"
• Haemoglobin A1c is superior to fasting glucose in predicting the incidence of diabetes over 8 years among Chinese - Diabetes Res Clin Pract. 2010 Dec 22 - "Baseline haemoglobin A1c had a higher standardized hazard ratio, and more optimal sensitivity and specificity than fasting glucose in predicting the 8-year incidence of diabetes among 530 non-diabetic Chinese from the population-based Hong Kong Cardiovascular Risk Factor Prevalence Study"
• Hemoglobin A1c between 5.7 and 6.4% as a marker for identifying pre-diabetes, insulin sensitivity and secretion, and cardiovascular risk factors: The Insulin Resistance Atherosclerosis Study (IRAS) - Diabetes Care. 2010 Jun 23 - "impaired glucose tolerance (IGT) ... impaired fasting glucose (IFG) ... A1C(5.7-6.4%) is less sensitive for detecting at-risk individuals than IFG and IGT, particularly among non-Hispanic whites. Single determinations of FPG and 2-h PG appear more precise correlates of insulin resistance and secretion than A1C and in general better for other metabolic disorders"
• A1c Levels: Is Lower Always Better? - Medscape, 4/23/10 - "A1c values in the lowest decile (median, 6.4%) were associated with an increased risk for mortality for all patients (hazard ratio [HR], 1.52; 95% confidence interval [CI], 1.40-1.64). This finding was stronger in the INS cohort (HR, 1.79; 95% CI, 1.45-1.22) than in the SUMET cohort (HR, 1.30; 95% CI, 1.07-1.58). Only the 10th decile (median, 10.4%) was also associated with increased mortality risk in the SUMET cohort (HR, 1.93; 95% CI, 1.55-2.42); but in the INS cohort, deciles 2 (median, 6.95%; HR,1.45; 95% CI, 1.17-1.80), 3 (median, 7.3%; HR, 1.35; 95% CI, 1.09-1.67), 9 (median, 9.4%; HR, 1.46; 95% CI, 1.21-1.77), and 10 (median, 10.6%; HR, 1.80; 95% CI, 1.49-2.17) were all associated with greater risk. The combined model yielded results similar to the INS cohort, and the inclusion of a variable for membership in the INS cohort was significantly associated with increased mortality (HR, 1.49; 95% CI, 1.39-1.59). The adjusted risk for progression to large-vessel disease had the same general U-shaped association as for all-cause mortality, and insulin treatment was associated with an increased risk for a first large-vessel disease event"
• Hemoglobin A1c outperforms fasting glucose for risk prediction - Science Daily, 3/3/10 - "Measurements of hemoglobin A1c (HbA1c) more accurately identify persons at risk for clinical outcomes than the commonly used measurement of fasting glucose ... people with HbA1c levels between 5.0 to 5.5 percent were identified as being within "normal" range ... With each incremental HbA1c increase, the study found, the incidence of diabetes increased as well; those at a level of 6.5 percent or greater are considered diabetic, and those between 6.0 and 6.5 percent are considered at a "very high risk" (9 times greater than those at the "normal" range) for developing diabetes"
• Effect of age and race/ethnicity on HbA1c levels in people without known diabetes mellitus: Implications for the diagnosis of diabetes - Diabetes Res Clin Pract. 2010 Jan 8 - "Over 90% of all race/ethnicity groups would have diabetes with HbA1c levels >/=7.0% ... we recommend an HbA1c level of >/=7.0% to diagnose diabetes"
• A1C Blood Test OK for Diabetes Diagnosis - WebMD, 12/29/09
• HbA1c Treatment Targets Cut CV Risk in Diabetics With Few Comorbidities - Medscape, 12/16/09 - "aggressive control of glycated hemoglobin (HbA1c) levels--that is, to no higher than 6.5% or 7%--significantly improves cardiovascular risk over five years, but only in patients who aren't too old or sick at the outset"
• HbA1c Levels Predict Carotid IMT in Diabetic Adolescents - Medscape, 11/13/09 - "For every 1% increase in HbA1c, the likelihood of having a thicker common carotid IMT increased by 35%, after adjustment for sex, systolic blood pressure z-score, and insulin use ... These data suggest that poor glycemic control is associated with structural changes in the carotid artery that are consistent with early atherosclerosis"
• HbA1c is associated with intima media thickness in individuals with normal glucose tolerance - Diabetes Care. 2009 Oct 6 - "normal glucose tolerant individuals (NGT) ... 1h-glucose and HbA1c were significantly correlated to carotid IMT in individuals with NGT, while fasting and 2h-glucose were not informative. Only HbA1c was associated with IMT independent of other confounders, while 1h-glucose was not informative ... HbA1c was the most informative glycemic marker with respect to IMT in individuals with NGT"
• Erectile function in men with diabetes type 2: correlation with glycemic control - Int J Impot Res. 2009 Sep 17 - "the level of HbA(1c) is significantly higher with declining degrees of potency (P-value=0.003). Also, there is an association between potency degree and glycemic control (P=0.002). We conclude that glycemic control is independently and inversely associated with ED in men with diabetes type 2"
• Efficacy and safety of therapy with metformin plus pioglitazone in the treatment of patients with type 2 diabetes: a double-blind, placebo-controlled, clinical trial - Curr Med Res Opin. 2009 Mar 23 - "Mean HbA(1c) was reduced by 0.67% in patients receiving pioglitazone plus metformin versus an increase of 0.25% in those receiving metformin alone (p < 0.0001). After 8 weeks' treatment and until the end of the study, HbA(1c) was significantly lower with pioglitazone plus metformin and more patients in this group achieved an HbA(1c) < 6.5% (38.6% vs. 8.1%; p < 0.0001). FBG was also reduced by a significantly greater amount in patients receiving pioglitazone plus metformin compared with metformin monotherapy (-20.5 vs. 1.9 mg/dl; p < 0.0001). Combination therapy was associated with significantly increased HDL-cholesterol, total cholesterol, and adiponectin, and significantly decreased levels of fasting insulin, free fatty acids, and homeostasis model assessment insulin resistance (HOMA-R) compared with metformin monotherapy" - See pioglitazone at OffshoreRx1.com.
• Diabetes Linked To Cognitive Deterioration - Science Daily, 3/5/09 - "people with diabetes were 1.5 more likely to experience cognitive decline, and 1.6 more likely to suffer from dementia than people without diabetes ... suggests that higher-than-average levels of blood glucose (blood sugar) may have a role in this relationship ... in people with type 2 diabetes, higher levels of haemoglobin A1C (a measure of average blood glucose) are significantly associated with poorer performance on three cognitive tasks which require memory, speed and ability to manage multiple tasks at the same time. A higher A1C level was also associated with a lower score on a test of global cognitive function ... lowering A1C levels could slow the accelerated rate of cognitive decline experienced by people with diabetes"
• Higher Blood Sugar Levels Linked to Lower Brain Function in Diabetics - Doctor's Guide, 2/11/09 - "The ongoing Memory in Diabetes (MIND) study, a sub-study of the Action to Control Cardiovascular Risk in Diabetes Trial (ACCORD), found a statistically significant inverse relationship between A1C levels over a period of 2 to 3 months and subjects' scores on four cognitive tests ... This study adds to the growing evidence that poorer blood glucose control is strongly associated with poorer memory function and that these associations can be detected well before a person develops severe memory loss"
• Doctors use diabetes test A1C as diagnostic tool- USA Today, 2/1/09 - "Within the next six months, a consensus by several leading diabetes organizations will lead to the publication of guidelines recommending the A1C test as a diagnostic tool for type 2 diabetes ... The benefit of the A1C test is that it can be taken at any time of day and is not thrown off by events of the day ... People who don't have diabetes typically have about a 6 or less reading"
• HemoglobinA1c level in healthy Thai adults: reference interval and fasting plasma glucose - Diabetes Res Clin Pract. 2009 Feb;83(2):e43-6. Epub 2009 Jan 8 - "Reference interval of HbA1c IFCC was 2.90-4.90%" - Note:  I saw this abstract last month and deleted it and have been thinking about it ever since so I did a medline search of "hba1c thailand" and found it again.  The point is that the range of hba1c was 2.90-4.90% in non-diabetics in Thailand.  Mine is 4.97% and I had two doctors tell me that was great.  In my opinion, and I'm not a doctor (Bachelor of Science in Electrical Engineering), American doctors are so used to seeing a high hba1c that they've lost track of what's normal.
• HbA1c Tied to Cardiovascular Risks in Patients With Symptomatic HF - Medscape, 8/28/08 - "Over a median follow-up period of almost 3 years, the researchers found that for each 1% rise in HbA1c, the risk of cardiovascular death, heart failure hospitalization and overall mortality rose by about 25%. Moreover, this was true in subjects with and without a history of diabetes and whether or not ejection fraction was reduced or preserved"
• Comparison of the effects of telmisartan and olmesartan on home blood pressure, glucose, and lipid profiles in patients with hypertension, chronic heart failure, and metabolic syndrome - Hypertens Res. 2008 May;31(5):921-9 - "telmisartan had more beneficial effects on glucose and lipid profiles in patients with relatively high HbA1c, serum total and low-density lipoprotein cholesterol, and triglyceride levels. Therefore, we concluded that telmisartan was more beneficial than olmesartan for controlling blood pressure in the early morning, as well as for improving glucose and lipid profiles in patients with hypertension, chronic heart failure, and metabolic syndrome" - Click here for why I feel that telmisartan should be the first line treatment for hypertension.
• HbA1C, but not serum glycated albumin, is elevated in late pregnancy due to iron deficiency - Diabetes Care. 2008 Jul 3 - "HbA(1C) levels were elevated in late pregnancy due to iron deficiency. Serum GA may offer a better index for monitoring glycemic control in pregnancy"
• Translating the A1C Assay Into Estimated Average Glucose Values - Diabetes Care. 2008 Jun 7 - "28.7 x A1C - 46.7"
• Hemoglobin A1C Levels Strongly Linked to Subsequent Mortality in Diabetes - Medscape, 6/9/08 - "For participants without a previous diagnosis of diabetes, HRs for all-cause mortality steadily increased from the A1C reference category to the highest category (≥ 7.0%; HR, 2.36; 95% confidence interval [CI], 1.72 - 3.25). In addition, A1C was associated with mortality from circulatory, endocrine, nutritional, metabolic, and immune diseases as well as from other and unknown causes"
• New Insights In Diagnosing Diabetes May Help The Millions Who Are Undiagnosed - Science Daily, 5/27/08 - "The measurement of HbA1c does not require fasting, while current accepted tests require the patient to fast for at least eight hours. Furthermore, HbA1c more accurately reflects longer-term glucose concentration in the blood; other tests can easily be affected by short-term lifestyle changes, such as a few days of dieting or exercise. And finally, HbA1c laboratory methods are now well standardized and reliable ... HbA1c greater than 6 percent would qualify as being in need of follow-up; HbA1c greater than or equal to 6.5 percent confirmed by a glucose-dependent test should establish the diagnosis of diabetes" - Note:  I feel there is something to this.  My fasting glucose is always high yet my HbA1c is 4.97 (normal 4.7 to 6.2) and my 2 hour fasting glucose bounces a point or two about the low normal.
• The Relationship Between A1C Levels & PAD Severity - Physician's Weekly, 11/19/07
• Rosiglitazone Reduces Liver Fat and Insulin Requirements While Improving Hepatic Insulin Sensitivity And Glycemic Control In Patients With Type 2 Diabetes Requiring High Insulin Doses - J Clin Endocrinol Metab. 2007 Oct 23 - "During rosiglitazone, HbA1c decreased from 8.9+/-0.4% to 7.8+/-0.3% (p=0.007) and insulin requirements from 218+/-22 to 129+/-20 IU/day (p=0.002). Liver fat content decreased by 46+/-9% from 20+/-3% to 11+/-3% (p=0.0002). Hepatic insulin sensitivity, measured from the % suppression of endogenous glucose production by insulin, increased from -40+/-7% to -89+/-12% (p=0.001). The % change in liver fat correlated with the % decrease in HbA1c (r=0.53, p=0.06), insulin dose (r=0.66, p=0.014), and suppression of endogenous glucose production (r=0.76, p=0.003)"
• Insulin Linked to Colonic Polyps, Neoplasia - oncologystat.com, 10/23/07 - "those with poorly controlled diabetes, identified by a high serum level of hemoglobin A 1c (HbA 1c ), were significantly more likely to have advanced colonic adenomatous polyps, compared with diabetic patients with better glycemic control ... patients with poorly controlled diabetes were more than sixfold as likely to have advanced polyps and nearly sixfold as likely to have right-sided polyps, compared with patients who had better glycemic control. The average number of polyps found in poorly controlled patients was 5.5; in better-controlled patients, the average was 2.5 polyps per patient. Results from a third study reported at the meeting showed that having three or more polyps was the strongest predictor of risk for recurrent advanced neoplasia in the colon"
• The Association of Elevated HbA1c on the Behavior of Adenomatous Polyps in Patients with Type-II Diabetes Mellitus - Dig Dis Sci. 2007 Oct 16 - "colonic adenomatous polyps (APs) ... univariate analysis (UA) ... UA demonstrated that patients with poorly controlled DM-2 had a significantly increased incidence of right-sided APs (P = 0.001), a greater number of APs (P < 0.005), more advanced APs (P < 0.005), a younger age of presentation (P = 0.001), a history of smoking (P = 0.05), and greater use of exogenous insulin (P = 0.01). Logistic regression, as measured by HbA1c, demonstrated that poorly controlled DM-2 independently predicted a greater prevalence of right-sided AP, a more advanced lesion at the time of presentation, a greater number of polyps, and greater use of exogenous insulin"
• Hemoglobin A1c predicts diabetes but not cardiovascular disease in nondiabetic women - Am J Med. 2007 Aug;120(8):720-7 - "HbA1c levels are elevated well in advance of the clinical development of type 2 diabetes, supporting recent recommendations for lowering of diagnostic thresholds for glucose metabolic disorders. In contrast, the association of HbA1c with incident cardiovascular events is modest and largely attributable to coexistent traditional risk factors"
• Thiazolidinedione increases serum soluble receptor for advanced glycation end-products in type 2 diabetes - Diabetologia. 2007 Jul 18 - "At 6 months, both rosiglitazone and sulfonylurea resulted in a significant reduction in HbA(1c), fasting glucose and AGE"
• Relation of increased hemoglobin a(1c) levels to severity of peripheral arterial disease in patients with diabetes mellitus - Am J Cardiol. 2007 May 15;99(10):1468-9 - "the higher the hemoglobin A(1c) levels in patients with diabetes with PAD, the higher the prevalence of severe PAD"
• New Data Shows Rimonabant Benefited Patients with Type 2 Diabetes by Improving Blood Sugar Control, Reducing Weight and Acting on Other Cardiometabolic Risk Factors - Doctor's Guide, 12/5/06 - "treatment-naive type 2 diabetes patients receiving rimonabant 20mg per day for a duration of six months significantly lowered their HbA1c levels by 0.8% from a baseline value of 7.9 as compared to a reduction of 0.3% in the placebo group (P =.002). In addition, patients with an HbA1c level greater than or equal to 8.5% at baseline, significantly reduced their HbA1c by 1.9% with rimonabant as compared to 0.7% with placebo" - See rimonabant at International Antiaging Systems.
• HbA1c - the gold standard in the assessment of diabetes treatment? - Dtsch Med Wochenschr. 2006 Dec;131 Suppl 8:S243-6
• Chronically High Blood Sugar Linked To Risk Of Cognitive Impairment - Science Daily, 8/9/06 - "Women with a glycosylated hemoglobin of seven percent or higher at baseline were four times more likely to develop MCI or dementia than women who tested at less than seven percent"
• Periodontal Therapy May Help Diabetic Patients Improve Sugar Control - Doctor's Guide, 4/12/06 - "periodontal therapy may reduce a diabetic patient's HbA1c count by as much as 20% at three and six months following treatment"
• High Blood Sugar Levels a Risk Factor for Heart Disease - Doctor's Guide, 9/14/05 - "Lowering blood sugar levels could reduce the risk of coronary heart disease in both diabetics and non-diabetics ... Non-diabetic persons with HbA1c levels of 6% or higher had almost a two-fold greater heart disease risk compared to persons with an HbA1c level below 4.6%"
• Rimonabant Study Shows Significant Improvements in Hba1c and Cardiometabolic Risk Factors in People With Type 2 Diabetes - Doctor's Guide, 6/16/05
• Metabolic Effect of Telmisartan [Micardis] and Losartan [Cozaar] in Hypertensive Patients with Metabolic Syndrome - Cardiovasc Diabetol. 2005 May 15;4(1):6 - "Telmisartan, but not losartan, significantly (p < 0.05) reduced free plasma glucose, free plasma insulin, homeostasis model assessment of insulin resistance and HbAic. Following treatment, plasma glucose and insulin were reduced during the oral glucose tolerance test by telmisartan, but not by losartan. Telmisartan also significantly reduced 24-hour mean systolic blood pressure (p < 0.05) and diastolic blood pressure (p < 0.05) compared with losartan"
• Glycosylated haemoglobin levels and the severity of erectile function in diabetic men - BJU Int. 2005 Mar;95(4):615-7 - "This study suggests that the severity of ED is associated with increasing HbA(1c) levels in diabetic men"
• High-Dose Atorvastatin Associated with Worsening Glycemic Control - Doctor's Guide, 11/10/04 - "Atorvastatin was associated with a statistically significant increased risk of developing an HbA1c greater than 6 -- both in non-diabetics and in diabetics"
• Death Risk Rises With Blood Sugar - WebMD, 9/20/04 - "As your blood sugar level goes up, so does your risk of death and heart disease - even if you don't have diabetes ... every 1% increase in HbA1c ups the risk of death -- from all causes -- by 24% for men and 28% for women ... These are important studies because they show we should be concerned about blood glucose elevations even in people who do not have diabetes"
• Hormone Therapy May Need to be Used Cautiously in Patients Taking Rosiglitazone - Doctor's Guide, 9/19/03 - "rosiglitazone reduced glucose levels from a mean of 9.15 to 7.5 mM/L; (P=0.013), insulin from 11.7 to 8.8 mU/L (P=0.026), haemoglobin A1c from 8.0% to 6.9% (P=0.001), triglycerides from 2.3 to 1.8 mM/L (P=0.009), systolic BP from 130 to 117 mm Hg (P=0.02), diastolic BP from 72 to 67 mm"
• Indications and Management Strategies for Insulin Therapy in the Treatment of Type 2 Diabetes - Doctor's Guide, 9/8/03 - "The American Diabetes Association goals for glucose control are a haemoglobin A1c level of less than 7%, a fasting glucose level between 90 and 130 mg/dL, and a post-prandial glucose concentration of less that 180 mg/dL"