Racial disparities in all-cause mortality among veterans with type 2 diabetes

Abstract

Background: Racial differences in mortality among veterans with diabetes are less well characterized than those in the general population.

Objective: To examine racial differences in all-cause mortality in a large sample of veterans with diabetes.

Design: A retrospective cohort.

Participants: Participants comprised 8,812 veterans with type 2 diabetes.

Measurements: The main outcome measure was time to death. The main predictor was race/ethnicity. Other risk factors (or covariates) included age, gender, marital status, employment, glycosylated hemoglobin (HgbA1c), and several ICD-9 coded physical and mental health comorbidities.

Results: Average follow-up was 4.5 years; 64% of veterans were non-Hispanic whites (NHW), 97% male, and 84% at least 50 years old. The overall mortality rate was 15% and was significantly lower for non-Hispanic blacks (NHB). Baseline HgbA1c values also differed for NHW (mean = 7.05) and NHB (mean = 7.65) (p < 0.001). In sequentially-built models NHB race was associated with a lower risk of mortality with HR ranging 0.80-0.92. After adjusting for all significant covariates, the risk of mortality remained lower for NHB (HR = 0.84, 95% CI: 0.75, 0.94). Increased mortality risk was associated with age, not being employed or retired, poor glycemic control, cancer, Coronary Heart Disease (CHD), and anxiety disorder; while a lower risk was associated with being female and ever being married.

Conclusions: The risk of death among NHB veterans with diabetes remained significantly lower than that of NHW after controlling for important confounding variables. Future studies in the VA need to examine detailed contributions of patient, provider and system-level factors on racial differences in mortality in adults with diabetes, especially if the findings of this study are replicated at other sites or using national VA data.

Figure 1

Survival curve for time to death by racial group and glycemic control.