Abstract / Summary
Abstract Objective We aimed to evaluate the association between bariatric surgery (BS) and the incidence of dementia and Parkinson’s disease. To assess consistency with established benefits of BS, we examined its association with cardiovascular disease, obesity-associated cancers, and all-cause mortality. Methods We conducted a longitudinal cohort study using electronic health records from TriNetX network. Patients aged ≥16 years with at least one BMI record of ≥35 kg/m 2 between 1st Jan 2005 and 31st Dec 2022 were included. The exposed cohort included those who underwent a BS; the unexposed cohort included everyone without BS. The index date was the earliest date for BS up to 6 months after a BMI of ≥35 kg/m 2 for the exposed, and the earliest encounter code up to 6 months after a BMI of ≥35 kg/m 2 for the unexposed. Individuals were 1:1 matched using propensity score matching on covariates age at index date, gender, ethnicity, race, BMI, hypertension, type 2 diabetes (T2D), socioeconomic status, smoking, alcohol, and history of neurological diseases. Cox proportional hazards regressions were performed for each outcome. Results After matching, there were 32,552 individuals each in the BS and non-BS group. The median follow-up was 4.7 years in individuals with BS and 5.9 years in those without. Compared to the non-BS group, individuals who underwent BS had significantly reduced incidence rates of dementia (hazard ratio 0.48, 95% CI: 0.39–0.58) and Parkinson’s disease (0.70; 0.51–0.96). Similar associations were observed for CVD (0.53; 0.51–0.56); obesity-associated cancers (0.66; 0.60–0.72) and all-cause death (0.46; 0.41–0.51). Survival probability at 20-years was 84.7% (95% CI: 71.1–92.3%) in the BS group vs 81.8% (77.5–85.4%) in those without. Conclusion BS was associated with a lower incidence of dementia and Parkinson’s disease in individuals with BMI ≥ 35 kg/m 2 , in addition to reducing CVD, obesity-associated cancers, and mortality, suggesting potential neuroprotective and systemic health benefits.