Headache after hemorrhagic stroke: A systematic review and meta‐analysis.

BACKGROUND/OBJECTIVE: Hemorrhagic stroke comprises about 20% of all strokes, with intracerebral hemorrhage (ICH) being the most common type. While post-stroke care often focuses on motor and functional recovery, post-stroke headaches remain underrecognized and understudied. This study aimed to summarize and pool the evidence on the prevalence and patterns of headaches after hemorrhagic stroke. METHODS: We conducted a systematic review and meta-analysis of studies published from database inception to December 2024, identifying observational studies that investigated headaches after hemorrhagic stroke. Studies enrolling five or more adult patients were included. Meta-analyses were conducted to estimate pooled prevalence of overall, acute/subacute, persistent, and severe headaches. Acute/subacute headache was defined as onset within 3 months of stroke, while persistent headache as headache lasting more than 3 months. Severe headache was defined as either a ≥ 7/10 pain intensity or functional impairment. RESULTS: Twenty-four studies comprising 4688 patients (58.2% female; mean age 56.9) were included. The overall pooled headache prevalence of 46.1% (95% confidence interval [CI]: 36.3%-56.1%; 95% prediction interval [PI]: 4.3%-91.8%; I2 = 96.7%) following hemorrhagic stroke. Stratified analyses showed that the prevalence was 58.3% (95% CI: 44.4%-71.6%, I2 = 97.5%) in patients with subarachnoid hemorrhage (SAH) and 36.1% (95% CI: 26.7%-46.0%, I2 = 93.9%) in those with ICH. Acute/subacute headache occurred in 55.9% (95% CI: 41.1%-70.1%; I2 = 97.6%), while persistent headache occurred in 36.7% (95% CI: 25.6%-48.5%, I2 = 93.1%). Severe headaches were reported in 42.7% (95% CI: 15.8%-72.1%; I2 = 98.0%) of patients with acute/subacute headache and 14.3% (95% CI: 10.4%-18.7%; I2 = 71.5%) with persistent headache. In both SAH and ICH, headaches frequently become chronic. No significant differences were observed by study design, geographic region, Human Development Index, or risk of bias. CONCLUSION: Headache is a common but understudied condition that can manifest at or soon after a hemorrhagic stroke and can persist for years, potentially contributing to long-term morbidity. Standardized headache definitions and longitudinal assessments are needed to improve recognition and inform future clinical trials targeting this underappreciated source of post-stroke morbidity. Further research is essential to better understand the nature of these headaches, which will help shape treatment protocols and enhance patient care.