Sex differences in risk factors for coronary heart disease events: a prospective cohort study in Iran

We investigated sex-specific associations and their differences between major cardiovascular risk factors and the risk of incident coronary heart disease (CHD) and hard CHD (defined as nonfatal myocardial infarction and CHD death). A total of 7518 (3377 men) participants from the Tehran Lipid and Glucose Study were included. Cox models were used to estimate the hazard ratios (HRs) and women-to-men ratios of HRs for CHD events associated with each risk factor. During 20 years of follow-up (1999-2018), 1068 (631 men) and 345 (238 men) new cases of CHD and hard CHD, respectively, were documented. In total population, the incidence rates per 1000 person-years were 9.5 (9.0-10.1) and 2.9 (2.6-3.2) for CHD and hard CHD, respectively. Hypertension, diabetes, pre-diabetes, and a high waist-to-hip ratio (WHR) were associated with a greater HR of hard CHD in women than men; the women-to-men HRs were 2.85 [1.36-5.98], 1.92 [1.11-3.31], 2.04 [1.09-3.80] and 1.42 [1.10-1.82], respectively. Diabetes was associated with a higher HR of CHD in women than men (ratio of HRs 1.49 (1.10-2.01). In conclusion, we found that hypertension, diabetes, pre-diabetes, and high WHR conferred a greater excess risk of CHD events in women than in men, suggesting that Iranian women may require greater attention for the prevention of CHD events.