Diabetes is More Lethal in Mexicans and Mexican-Americans Compared to Non-Hispanic Whites

PURPOSE: To examine the mortality risk associated with diabetes in the Mexico City Diabetes Study (MCDS) and the San Antonio Heart Study (SAHS). METHODS: Prospective cohorts conducted 1990-2007 in MCDS and 1979-2000 in SAHS. Mortality risk was examined using Cox proportional hazard models in 1402 non-Hispanic whites (NHW), 1907 U.S.-born Mexican-Americans (MA), 444 Mexican-horn MA, and 2281 Mexico City residents (MCR) between the ages of 35-64. RESULTS: Age- and sex-adjusted mortality hazard ratios (FIR) comparing U.S.-born MA, Mexican-born MA, and MCR to NHW were 1.09(95% confidence interval [CI]: 0.86, 1.37), 1.23 (95% Cl: 0.86, 1.76), and 0.97 (95% Cl: 0.77, 1.23), respectively, in nondiabetic individuals; in contrast, mortality risk varied in diabetic individuals with respective HRs of 1.77 (95% Cl: 1.20, 2.61), 1.08 (95% Cl: 0.59, 1.97), and 2.27 (95% Cl: 1.53, 3.35) (interaction p = .0003). Excluding Mexican-born MA and nondiabetic individuals, controlling for medication use, insulin use, fasting glucose levels, and duration of diabetes explained a significant proportion of the mortality differential (HRs relative to NHW were 1.31 [95% Cl: 0.87, 1.981 in U.S.-born MA and 1.38(95% CI: 0.89, 2.121 in MCR). CONCLUSIONS: This study provides evidence that diabetes is more lethal in U.S.-born MA and MCR than in NHW. Ann Epidemiol 201121:899-906. (C) 2011 Elsevier Inc. All rights reserved.