Polycystic ovary syndrome (PCOS) has been associated with diabetes and
cardiovascular disease; however, whether the relationship is causal is
uncertain. We conducted a two-sample Mendelian randomization (MR) study to
investigate the associations of PCOS with type 2 diabetes, coronary heart
disease (CHD) and stroke. Association between PCOS and diabetes risk was examined
in European and Asian cohorts, both sex-specific and sex-combined. Causal
effects of PCOS on risks of CHD and stroke were evaluated in European cohorts.
Stroke was analyzed as any stroke as well as four sub-types of stroke
(ischemic, large artery, cardioembolic, small vessel). We found no association
of genetically predicted PCOS with risk of diabetes, CHD or stroke. This
suggests that PCOS in and of itself does not increase the risk of these
outcomes. Other features of PCOS (obesity, elevated testosterone, low sex
hormone binding globulin) may explain the association between PCOS and
cardiometabolic diseases. In light of these results, efforts to prevent
cardiometabolic complications in PCOS should focus on women with high-risk
factures, rather than all women with PCOS.
Polycystic ovary syndrome (PCOS) and the risk of coronary heart disease (CHD): a meta-analysis