Abstract 5026: Gender Differences In The Effect Of Hemoglobin A1c On Mortality In Adults with Diabetes: Findings From A National Population-based Follow-up Study
Background: Diabetes is associated with a greater relative risk of cardiovascular mortality in women than in men. Further, diabetes may carry a larger cardiovascular mortality risk than established coronary heart disease in women. It is unclear however if increasing glycosylated hemoglobin (HbA1c) levels are more strongly related to increased mortality in women than men.
Methods: We examined the relationship between increasing levels of HbA1c and subsequent all-cause and cardiovascular mortality in a cohort of self-reported diabetics using data from the Third National Health and Nutrition Examination Survey. Mortality outcomes were assessed from the national death index. Population hazard ratios (HR) with 95% confidence intervals (CI) for mortality were derived from Cox proportional hazards models adjusting for age, race, education, income, smoking, obesity, hypertension, hyperlipidemia, physical activity, and diabetes duration. The study’s complex survey design was incorporated in all analyses to obtain population estimates by utilizing the appropriate survey weights, strata, and cluster variables.
Results: There were a total of 1323 adults with diabetes with a mean follow-up time of 7.7 years. Among the 544 male diabetics, there were 235 all-cause deaths, 124 of which were from cardiovascular causes. Among the 779 female diabetics, there were 235 all-cause deaths, 111 of which were due to cardiovascular causes. In fully adjusted Cox models, a 2 percent increase in hemoglobin A1c was more strongly related to mortality in women (all-cause HR 1.23, 95% CI 1.04 –1.44, p=.02, cardiovascular HR 1.42, 95% CI 1.08 –1.85, p=.01) than in men (all-cause HR 1.17, 95% CI 0.88 –1.56, p=.27, cardiovascular HR 1.02, 95% CI 0.69 –1.54, p=.92). However, we did not find significant gender-Hemoglobin A1c interactions for either all-cause or cardiovascular mortality.
Conclusions: Increasing hemoglobin A1c may be more strongly related to increased all-cause and cardiovascular mortality in women than in men.