The risk of chronic kidney disease among women with polycystic ovary syndrome: A long‐term population‐based cohort study

Background and objective Results of studies focusing on chronic kidney disease (CKD) among women with polycystic ovary syndrome (PCOS) are insufficient and controversial. This study aimed to evaluate the incidence rate of CKD in women with PCOS, compared to a control group of healthy women. Methods This study was a population-based cohort study conducted from among 1460 reproductive-age women including 156 women with PCOS and 1304 controls. Incidence rates per 1000 person-years of follow-up were calculated for PCOS and control groups. Cox proportional hazards regression with age as the time-scale was used to estimate hazard ratios (HR) and 95% confidence intervals for developing CKD in relation to PCOS in both univariable and multivariable models. Results During a median follow-up of 12.9 years, 330 new cases of CKD were identified, including 25 PCOS women (14.8 per 1000 person-years; 95% CI, 10-22) and 305 healthy controls (21.5 per 1000 person-years; 95% CI, 19.2-24.1). The results of the Cox model showed that the risk of CKD among women with PCOS and healthy women is comparable and women with PCOS did not have a higher risk of developing CKD compared to healthy women (unadjusted HR: 0.883; 95% CI: 0.587-1.328; P = .551). The results remained unchanged after adjustment for potential confounders of smoking status, BMI, hypertension and diabetes at baseline and follow-up of study (multiple adjusted HR: 0.911; 95% CI: 0.600-1.383; P = .661). Conclusion Our population-based study with a long-term follow-up period showed that the risk of CKD in PCOS patients was similar to the general female population. Large studies, with long-term follow-up and more diverse phenotypes, are needed to confirm the findings.