Impact of incident diabetes and incident nonfatal cardiovascular disease on 18-year mortality: The Multiple Risk Factor Intervention Trial experience

OBJECTIVE - To report long-term risks for total, cardiovascular disease (CVD), and coronary heart disease (CHD) mortality associated with incident diabetes (using current diagnostic criteria) and with incident nonfatal CVD (NF-CVD). RESEARCH DESIGN AND METHODS - A total of 11,645 participants without diabetes or CVD at baseline from the Multiple Risk Factor Intervention Trial who survived to the end of the trial were grouped by during-trial incident diabetes and/or NF-CVD events: neither diabetes nor NF-CVD, diabetes only, NF-CVD only, or both diabetes and NF-CVD. Incident diabetes was defined by use of hypoglycemic agents or fasting glucose ≥126 mg/dl at any time over the 6 trial years. Proportional hazards models tested group differences in mortality over 18 post-trial years. RESULTS - Among 3,859 total deaths were 1,846 from CVD and 1,277 from CHD, with death rates per 10,000 person-years of 203, 97, and 67, respectively. Multivariate-adjusted hazard ratios (HRs) for total mortality were 2.75 (P < 0.0001) for those with NF-CVD and diabetes both, 1.92 (P < 0.0001) for those with NF-CVD only, and 1.49 (P < 0.0001) for those with diabetes only, relative to neither diabetes nor NF-CVD. NF-CVD was associated with a higher hazard of death than diabetes for total (HR 1.29, P = 0.0004), CVD (HR 1.76, P < 0.0001), and CHD (HR 1.88, P < 0.0001) mortality. Only the subgroup of participants on hypoglycemic agents showed an equivalent risk of total mortality relative to participants with NF-CVD (HR 0.93, P = 0.54). CONCLUSIONS - Current diabetes diagnostic criteria conferred significantly increased total, CVD, and CHD mortality risks independent of the impact of NF-CVD. NF-CVD was more strongly predictive of mortality.