Location specific risk factors for intracerebral hemorrhage: Systematic review and meta-analysis.

Jolink, Wilmar M T; Wiegertjes, Kim; Rinkel, Gabriël J E; Algra, Ale; de Leeuw, Frank-Erik; Klijn, Catharina J M

OBJECTIVE To conduct a systematic review and meta-analysis of studies reporting on risk factors according to the location of the intracerebral hemorrhage. METHODS We searched PubMed and Embase for cohort and case-control studies reporting on ≥100 patients with spontaneous intracerebral hemorrhage, that specified the location of the hematoma and reported associations with risk factors published until June 27th 2019. Two authors independently extracted data on risk factors. Estimates were pooled with the generic variance-based random effects method. RESULTS After screening 10 013 articles, we included 42 studies totaling 26 174 patients with intracerebral hemorrhage (9 141 lobar and 17 033 non-lobar). Risk factors for non-lobar intracerebral hemorrhage were hypertension (risk ratio 4.25, 95% confidence interval 3.05-5.91, I2=92%), diabetes (RR 1.35, 1.11-1.64, I2=37% ), male sex (RR 1.63, 1.25-2.14, I2=61%), alcohol overuse (RR 1.48, 1.21-1.81, I2=19%), underweight (RR 2.12, 1.12-4.01, I2=31%), and being black (RR 2.19, 1.21-3.96, I2=96%) or Hispanic (RR 2.13,0.94-4.81, I2=71%) in comparison with being white. Hypertension, but not any of the other risk factors, was also a risk factor for lobar intracerebral hemorrhage (RR 1.83, 1.39-2.42, I2=76%). Smoking, hypercholesterolemia and obesity were associated with neither non-lobar nor lobar intracerebral hemorrhage. CONCLUSIONS Hypertension is a risk factor for both non-lobar and lobar intracerebral hemorrhage, although with double the effect for non-lobar intracerebral hemorrhage. Diabetes, male sex, alcohol overuse, underweight, and being black or Hispanic are risk factors for non-lobar intracerebral hemorrhage only. Hence, the term "hypertensive intracerebral hemorrhage" for non-lobar intracerebral hemorrhage is not appropriate.