Endometriosis Might Be Inversely Associated with Developing Chronic Kidney Disease: A Population-Based Cohort Study in Taiwan.

This study was conducted to determine the risk of chronic kidney disease (CKD) among women with endometriosis in Taiwan. We conducted a retrospective cohort study using the National Health Insurance Research Database of Taiwan. A total of 27,973 women with a diagnosis of endometriosis and 27,973 multivariable-matched controls (1:1) from 2000 to 2010 were selected. Cox regression and computed hazard ratios (HR) with 95% confidence intervals (95% CI) were used to determine the risk of CKD among women with endometriosis. The incidence rates (IR, per 10,000 person-years) of CKD among women with and without endometriosis were 4.64 and 7.01, respectively, with a significantly decreased risk of CKD (crude HR 0.65, 95% CI 0.53-0.81; adjusted HR 0.69, 95% CI 0.56-0.86) among women with endometriosis. The IR of CKD progressively increased with age, but the trend of lower CKD risk among women with endometriosis was consistent. However, the lower risk of CKD in women with endometriosis was no longer statistically significant after adjusting for menopausal status (adjusted HR 0.85, 95% CI 0.65-1.10). The results suggest that endometriosis is inversely associated with CKD, but this effect was mediated by menopause. The possible mechanism of this association is worthy of further evaluation.