Association between preventive treatment for unruptured intracranial aneurysms and incident dementia: a nationwide population-based cohort study

Preventive treatments for unruptured intracranial aneurysms (UIAs) are used worldwide. However, the long-term effects to cognition have been underestimated. Using representative sample data from the National Health Insurance Service-Senior Cohort database, we compared cumulative risk of incident dementia between two groups: (1) treatment versus observation group, and (2) within the treatment group (surgical versus endovascular treatment). Cox proportional hazard ratios were estimated after applying one-to-one propensity score matching. Subgroup analyses were conducted to investigate interactions between treatment effects and sex, age and history of stroke, respectively. After matching, 3,763 participants were included in each group. The 10-year incidence rates of dementia were 9.82 and 8.68 per 1,000 person-years in the treatment and observation groups, respectively (HR: 1.11, 95% CI: 0.90–1.38, P = 0.33). Furthermore, the risk of incident dementia was not different between the surgical and endovascular treatment groups (HR: 0.98, 95% CI: 0.70–1.37, P = 0.91). In the subgroup analysis, surgical treatment was associated with an increased risk of developing dementia, particularly among male patient (HR: 2.34, 95% CI: 1.04–5.28). Preventive treatment of UIAs appears acceptable in terms of long-term effects to cognition. However, further researches are strongly required to identify the high risk patients of development of dementia.