Worldwide Incidence of Aneurysmal Subarachnoid Hemorrhage According to Region, Time Period, Blood Pressure, and Smoking Prevalence in the Population

Subarachnoid hemorrhage (SAH) from ruptured intracranial aneurysms is a subset of stroke with high fatality and morbidity. Better understanding of a change in incidence over time and of factors associated with this change could facilitate primary prevention.

To assess worldwide SAH incidence according to region, age, sex, time period, blood pressure, and smoking prevalence. Data Sources: We searched PubMed, Web of Science, and Embase for studies on SAH incidence published between January 1960 and March 2017. Worldwide blood pressure and smoking prevalence data were extracted from the Noncommunicable Disease Risk Factor and Global Burden of Disease data sets. Study Selection: Population-based studies with prospective designs representative of the entire study population according to predefined criteria. Data Extraction and Synthesis: Two reviewers independently extracted data according to PRISMA guidelines. Incidence of SAH was calculated per 100 000 person-years, and risk ratios (RRs) including 95% CIs were calculated with multivariable random-effects binomial regression. The association of SAH incidence with blood pressure and smoking prevalence was assessed with linear regression. Main Outcomes and Measures: Incidence of SAH.