Polycystic ovary syndrome and cardiovascular disease: a premature association?

Women with polycystic ovary syndrome (PCOS) are often assumed, a priori, to be at increased risk for cardiovascular disease (CVD), given the high prevalence of the metabolic syndrome X among them. There is, however, no single definition of PCOS, and for that reason a comparison of studies that have analyzed its association with CVD is compromised from the start. Long-term studies of well characterized women with PCOS are lacking, and the link to primary cardiovascular events such as stroke or myocardial infarction remains more speculative than substantive. Epidemiological studies that have focused on isolated signs and stigmata of PCOS, such as polycystic ovaries, hyperandrogenism, or chronic anovulation, have found mixed results. There are studies that suggest a slight increase in cardiovascular events in women with polycystic ovaries, with perhaps stronger evidence between an increased risk of cardiovascular events in women with menstrual irregularity. However, there is little evidence for an association between hyperandrogenism per se and cardiovascular events. Furthermore, there are less data to substantiate an increased risk of events in women with PCOS identified on the basis of a combination of signs and symptoms, such as hyperandrogenic chronic anovulation. The existing data suggest that PCOS may adversely affect or accelerate the development of an adverse cardiovascular risk profile, and even of subclinical signs of atherosclerosis, but it does not appear to lower the age of clinical presentation to a premenopausal age group. Future studies to identify the risk of cardiovascular events in women with PCOS will benefit from clear and extensive phenotyping of PCOS abnormalities at baseline, from a prospective design, from larger sample sizes, and from longer follow-up.