Association between hysterectomy and kidney stone disease: results from the National Health and Nutrition Examination Survey 2007-2018 and Mendelian randomization analysis.

Purpose: Hysterectomy is one of the most common types of gynecological operations and it is associated with numerous postoperative complications. Few studies have reported a definitive association between hysterectomy and kidney stone disease (KSD). This study aimed to explore whether hysterectomy increases the risk of KSD.

Methods: This is a cross-sectional study that used six continuous cycles of data obtained from the National Health and Nutrition Examination Survey from 2007 to 2018. The correlations between hysterectomy or age at hysterectomy and the prevalence of KSD were assessed using weighted multivariable-adjusted logistic regression. Further, five methods of two-sample Mendelian randomization (MR) were applied to decrease bias and infer causality in the observational study.

Results: After adjusting for potential confounders, hysterectomy (OR: 1.37, 95% CI 1.04-1.81) was found to be positively associated with the prevalence of KSD, whereas age at hysterectomy was found to be negatively associated with the prevalence of KSD (OR: 0.96, 95% CI: 0.94-0.98). In the inverse-variance weighted method, MR analyses suggested that genetically predicted hysterectomy is causally associated with a higher risk of KSD (OR: 11.961, 95% CI 1.12-1.28E2).

Conclusions: Hysterectomy could increase the risk of KSD. Younger age at hysterectomy is associated with a higher risk of KSD. Further prospective cohort studies with larger sample sizes and longer follow-up times are needed.