Introduction: Endometriosis is a chronic inflammatory condition that affects at least 10% of reproductive-age females and is associated with increased stroke risk. Current treatments, including oophorectomy and medications such as hormonal therapies and analgesics, can further elevate stroke risk. Despite the known relationship between traditional vascular risk factors and dementia, the relationship between endometriosis and long-term cognitive impairment is unknown. Methods: We compared the incidence of cognitive impairment, including dementia, in female patients over age 18 exposed versus unexposed to endometriosis using population-level United States emergency department and inpatient data from 2016 to 2020 from the Healthcare Cost and Utilization Project, a combined population of around 83 million residents, comprising 25% of the total US population. We used validated ICD-10-CM codes to identify patients with both cognitive impairment disorders and endometriosis. Cox proportional hazards regression with IP-weights were used to calculate hazard ratios (HR) with 95% confidence intervals (CI) reported. Results: A total of 193,942 patients with endometriosis (exposed) and 19,222,110 without endometriosis (unexposed), with a median follow up time of 5.18 years, were included. In the endometriosis group, 1,542 (0.8%) had a cognitive impairment diagnosis outcome versus 1,633,824 (8.5%) in the unexposed group. After adjusting for patient age and race-ethnicity, the risk of cognitive impairment diagnosis was lower in patients with endometriosis (HR 0.53, 95% CI: 0.50-0.56). Results did not change when additionally adjusted for vascular risk factors and Charlson comorbidities (HR 0.70, CI 0.58-0.83) or oophorectomy (HR 0.70, CI 0.58-0.83). Conclusions: Despite its association with stroke, we found that endometriosis was inversely associated with a diagnosis of cognitive impairment using large, population-level data. Limitations include the low event rate and the potential for residual confounding. Future studies are warranted to further explore reasons why, despite being associated with increased stroke risk, patients with endometriosis have a lower risk of cognitive impairment diagnosis.
Seitz et al. (Thu,) studied this question.