Diabetes and number of years of life lost with and without cardiovascular disease: a multi-state homogeneous semi-Markov model.

Abstract

We quantified the impact of type 2 diabetes on incidence of non-fatal cardiovascular disease (CVD) and mortality, considering CVD as a continuum from occurrence of diabetes to the end point, and estimated the 15-year life expectancy with and without CVD. A total of 7239 Iranian adults (3246 men), aged ≥30years, were followed from 1999 to 2014. We applied a multi-state semi-Markov model with three transitions including CVD-free to non-fatal CVD, CVD-free to death and non-fatal CVD to death, and studied the influence of diabetes on each transition rate, stratifying by sex and adjusting for confounders. Diabetes was significantly associated with increased risk of non-fatal CVD in men [hazard ratio, 1.70 (1.36-3.53)] and women [2.19 (1.74-2.77)], and of all-cause death [2.72 (2.03-3.63) and 1.92 (1.37-2.67) in men and women, respectively]. An increased risk of mortality was found only among diabetic men, when non-fatal CVD was occurred [2.19 (1.36-3.53)]. Men with diabetes experienced first non-fatal CVD and death without CVD 1.7 and 1.4years, respectively, earlier than those without diabetes; the corresponding values were 1.4 and 0.7years for women. Moreover, diabetic men lived 1.3years less than non-diabetic counterparts when non-fatal CVD was occurred. Diabetes increased the risk of non-fatal CVD events and all-cause mortality and consequently decreased the number of years lived without CVD. A decrease in LE was found only among diabetic men compared to non-diabetics after non-fatal CVD occurred.