Association between chronic hepatitis B virus infection and stroke risk: a propensity score-matched analysis.

Evidence on the association between chronic hepatitis B virus (HBV) infection and stroke is limited, inconsistent, and confined predominantly to endemic regions in Asia. This study investigated the association between chronic HBV infection and stroke using data from the largest healthcare provider in Israel. All individuals aged 20 and older who were tested for hepatitis B surface antigen (HBsAg) between 2005 and 2023 were identified. Newly diagnosed HBV patients (HBsAg-positive) were propensity scorematched to non-HBV subjects (HBsAg-negative) in a 1:4 ratio and followed for stroke occurrence through 2024. The study included 20 544 HBV patients and 82 176 matched controls. Overall stroke was diagnosed in 472 HBV patients and 1 717 controls (incidence rates: 2.13 vs. 1.94 per 1 000 person-years). Hazard ratios were 1.09 (95% CI, 0.98-1.22) for overall stroke, 1.01 (0.89-1.14) for ischemic stroke, and 1.82 (1.35-2.45) for intracerebral hemorrhage (ICH). Ischemic stroke risk was specifically increased in younger individuals and females (p-for-interaction = 0.006 and 0.079, respectively). Results remained consistent when excluding patients with prior stroke. Exploratory analysis suggested hepatitis D coinfection is associated with increased ICH risk. In conclusion, chronic HBV infection was associated with significantly increased ICH risk, with subgroup-specific increases in ischemic stroke risk.