Results
As shown in Table 1, we included 5927 patients with PCOS from 2000 to 2012 and 23708 patients without PCOS. The mean follow-up time of the case cohort was 6.80 (±3.56) years. The participants in our study were mainly aged from 20-30 years old (60%). The mean age was about 29 years old. The proportion of patients with comorbidities was similar in both cohorts.
The incidence rate of Graves’ diseases for PCOS patients was 1.46 per 1000 person-years and that of non-PCOS patients was 1.06 per 1000 person-years (Table 2.). Figure 1 presented the cumulative incidence curve of Graves’ diseases in patients with PCOS was significantly higher than that in the patient without PCOS (Log-rank test: p-value=0.03). The adjusted hazard ratio (aHR) of Graves’ disease for the PCOS cohort relative to the non-PCOS cohort was 1.34 (95% CI=1.00-1.81). Patients with CAD and DM increased the risk of Graves’ disease by 2.66 (95% CI = 1.08-6.56) and 2.17 (95% CI = 1.06, 4.44) folds, respectively.
Table 3 presents the stratification analysis of the association of PCOS and Graves’ disease in each age group and comorbidities. PCOS patients aged 31-40 had a higher risk of Graves’ disease (aHR=2.31, 95%CI=1.48-3.61). The independent association of PCOS with Graves’ disease was significant in patients without anxiety, COPD, or hypertension. For patients with hyperlipidemia, PCOS raises the risk of Graves’ disease by 10.2 (95% CI=1.21, 85.1) times.