Sex differences in associations of comorbidities with incident cardiovascular disease: focus on absolute risk.

ABSTRACT

Aim: To examine sex differences in associations of obesity, type-2 diabetes, hypertension, and atrial fibrillation (AF) with incident cardiovascular disease (CVD), focusing on absolute risk measures. Methods and results: We included a total of 7994 individuals (mean age 49.1 years; 51.2% women) without prior CVD from the PREVEND (Prevention of Renal and Vascular End-stage Disease) cohort with a median follow-up of 12.5 years. Using Poisson regression, we calculated the increase in absolute as well as relative CVD risk associated with a comorbidity using incidence rate differences (IRD = IRcomorbidity-IRno-comorbidity) and incidence rate ratios (IRR = IRcomorbidity/IRno-comorbidity), respectively. Sex differences were presented as women-to-men differences (WMD = IRDwomen-IRDmen) and women-to-men ratios (WMR = IRRwomen/IRRmen). Absolute CVD risk was lower in women than in men (IRwomen 6.73 vs. IRmen 14.58 per 1000 person-years). While increase in absolute CVD risk associated with prevalent hypertension was lower in women than in men [WMD -6.12, 95% confidence interval (-9.84 to -2.40), P = 0.001], increase in absolute CVD risk associated with prevalent obesity [WMD -4.25 (-9.11 to 0.61), P = 0.087], type-2 diabetes [WMD -1.04 (-14.36 to 12.29), P = 0.879] and AF [WMD 18.39 (-39.65 to 76.43), P = 0.535] did not significantly differ between the sexes. Using relative risk measures, prevalent hypertension [WMR 1.49%, 95% confidence interval (1.12-1.99), P = 0.006], type-2 diabetes [WMR 1.73 (1.09-2.73), P = 0.019], and AF [WMR 2.53 (1.12-5.70), P = 0.025] were all associated with higher CVD risk in women than in men. Conclusion: Increase in absolute risk of developing CVD is higher in hypertensive men than in hypertensive women, but no substantial sex-related differences were observed among individuals with obesity, type-2 diabetes and AF. On a relative risk scale, comorbidities, in general, confer a higher CVD risk in women than in men.