Glycated Hemoglobin and All-Cause and Cause-Specific Mortality Among Adults With and Without Diabetes

Abstract

<jats:title>Abstract</jats:title> <jats:sec> <jats:title>Context</jats:title> <jats:p>The patterns of associations between glycated Hb (HbA1c) and mortality are still unclear.</jats:p> </jats:sec> <jats:sec> <jats:title>Objective</jats:title> <jats:p>To explore the extent to which ranges of HbA1c levels are associated with the risk of mortality among participants with and without diabetes.</jats:p> </jats:sec> <jats:sec> <jats:title>Design, Setting, and Patients</jats:title> <jats:p>This was a nationwide, community-based prospective cohort study. Included were 15,869 participants (median age 64 years) of the Health and Retirement Study, with available HbA1c data and without a history of cancer. Cox proportional hazards regression models were used to estimate hazard ratios with 95% CIs for mortality.</jats:p> </jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>A total of 2133 participants died during a median follow-up of 5.8 years. In participants with diabetes, those with an HbA1c level of 6.5% were at the lowest risk of all-cause mortality. When HbA1c level was &amp;lt;5.6% or &amp;gt;7.4%, the increased all-cause mortality risk became statistically significant as compared with an HbA1c level of 6.5%. As for participants without diabetes, those with an HbA1c level of 5.4% were at the lowest risk of all-cause mortality. When the HbA1c level was &amp;lt;5.0%, the increased all-cause mortality risk became statistically significant as compared with an HbA1c level of 5.4%. However, we did not observe a statistically significant elevated risk of all-cause mortality above an HbA1c level of 5.4%.</jats:p> </jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>A U-shaped and reverse J-shaped association for all-cause mortality was found among participants with and without diabetes. The corresponding optimal ranges for overall survival are predicted to be 5.6% and 7.4% and 5.0% and 6.5%, respectively.</jats:p> </jats:sec>

Diabetes duration and glycaemic control as predictors of cardiovascular disease and mortality

“…However, the cause of increased morbidity and mortality for participants with diabetes with low HbA1c remains unclear. Hypoglycaemia or drug interactions caused by different medications may contribute to the excess health risks 40 …”

The Significant Association between Health Examination Results and Population Health: A Cross-Sectional Ecological Study Using a Nation-Wide Health Checkup Database in Japan

“…The relation between HbA1c and all-cause mortality in non-diabetic examinees was reportedly reverse J-shaped with an HbA1c of 5.4% as the lowest mortality risk. All-cause mortality risk does not increase significantly above an HbA1c level of 5.4% for non-diabetic examinees, although the risk is significantly higher in the low range, i.e., less than 5.0% [ 39 ]. Given that most participants were non-diabetic individuals, the result seemed consistent with this literature.…”

Higher blood pressure in normal weight women with PCOS compared to controls

“…In the age groups of 18–34, 35–44, 45–54, 55–64, 65–74, and 75–99 years, each 1 mmol/L higher level for total cholesterol ≥ 5.2 mmol/L, increased mortality by 14, 13, 8, 7, 6, and 3%, respectively ( 32 ). HbA1c and blood glucose is associated with all-cause mortality also in individuals without T2D ( 33 , 34 ), and the association between glucose and mortality is closer at younger ages ( 35 ). Our findings suggest that the same metabolic risk markers are relevant in women with PCOS as in other study populations.…”