Objective: To investigate the prevalence of polycystic ovary syndrome (PCOS) and its comorbidities in patients with autoimmune thyroid disease (AITD). Population: In this cohort study, patients newly diagnosed as having Hashimoto thyroiditis (HT) or Grave disease (GD) were recruited into the AITD group. Method: The logistic regression model was used to investigate the association between exposure, endpoint, later diseases and treatment. Main Outcome Measures: We assessed the cumulative incidence using the Kaplan-Meier method and verified the difference by the log-rank test. Results: The AITD group included 3599 GD patients and 1332 HT patients. PCOS risk in patients with AITD was higher than that in the control group (adjusted hazard ratio = 1.39; 95% confidence interval = 1.07-1.71). In patients with both AITD and PCOS, the odds ratios of diabetes, hyperlipidemia and coronary artery disease were 2.48, 2.05 and 2.63, respectively. Conclusions: The risks of PCOS and its comorbidities such as diabetes, dyslipidemia and cardiac artery disease are high in patients with AITD in Taiwan.
