GLP-1 Receptor Agonist Use Is Associated With Lower Risk of Intracranial Aneurysm Rupture and Rupture Severity

BACKGROUND: Unruptured intracranial aneurysms (UIAs) affect up to 5% of the population, and rupture can lead to devastating subarachnoid hemorrhage. GLP-1RAs (glucagon-like peptide-1 receptor agonists) have anti-inflammatory and vasculoprotective effects, but their impact on aneurysm stability and subarachnoid hemorrhage outcomes is unexplored. This study evaluated whether GLP-1RA use is associated with reduced rupture risk and attenuated severity in the event of a rupture. METHODS: We conducted a retrospective cohort study using the TriNetX US Collaborative Network (2016–2024). Cohort 1 included patients with newly diagnosed, untreated UIA; cohort 2 included those who suffered aneurysm rupture. GLP-1RA exposure was defined as use before or within 3 months of UIA diagnosis (cohort 1) or before rupture (cohort 2). The primary outcome was aneurysm rupture risk in cohort 1. Secondary outcomes include presentation severity, vasospasm, and mortality in cohort 2. Propensity score matching balanced demographics, comorbidities, and medications. RESULTS: After propensity score match, cohort 1 of patients with untreated UIA included 8088 GLP-1RA users and 8088 nonusers. GLP-1RA use was associated with significantly lower probabilities of aneurysm rupture at 1-year (0.65% versus 1.51%; P <0.001), 3-year (1.18% versus 1.85%; P <0.001), and 5-year (1.49% versus 2.10%; P <0.001) timepoints, representing a 48% decrease in hazards (hazard ratio, 0.52 [95% CI, 0.38–0.69]). Among patients who suffered aneurysm rupture (cohort 2, N=298 after propensity score match), prerupture GLP-1RA use (n=149) was associated with lower rates of intraparenchymal hemorrhage (17.4% versus 33.6%; P <0.001), intraventricular hemorrhage (10.1% versus 23.5%; P <0.001), and clinically significant vasospasm (10.7% versus 24.2%; P =0.002), as well as numerically lower rates of 30-day mortality (9.4% versus 14.1%; P =0.21). CONCLUSIONS: For patients with untreated UIA, GLP-1RA use was associated with a 48% reduction in aneurysm rupture risk and, among those who suffered aneurysm rupture, milder clinical and radiographic severity. These findings suggest possible neuroprotective and vascular stabilizing effects of GLP-1RAs for patients with UIA.