The Effect of Statins on the Recurrence of Chronic Subdural Hematomas: A Systematic Review and Meta-Analysis

Background: Statins have been proposed to improve the resolution of chronic subdural hematoma (cSDH), with conflicting results likely due to underpowered analysis or confounding factors, such as the use of antithrombotic medication. We performed a systematic literature review and meta-analysis to better elucidate the effect of statin therapy on cSDH recurrence. Methods: We performed a comprehensive search of PubMed, MEDLINE, and Embase databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Articles were included if the number of recurrences requiring surgical evacuation or leading to neurological deterioration was reported and could be extracted separately for patients who did or did not receive statin therapy. Results: Seven studies were included, comprising 1359 cSDH patients (statin therapy, 449 vs. non-statin therapy, 910). Age was not different between groups (P = 0.548). The proportion of men was significantly different (statin, 80.1% vs. non-statin, 74.7%; P = 0.02). Use of antithrombotic medication was significantly higher (P = 0.005) in the statin group (11.7%) than in the non-statin group (7.3%). The statin group had a non-significant lower odds of recurrence (odds ratio 0.80, 95% confidence interval 0.35–1.81). In an exploratory data analysis of 4 studies without a difference between groups in antithrombotic medication use, the statin group had significantly lower odds of recurrence (odds ratio 0.29, 95% confidence interval 0.17–0.50). Conclusions: Overall, we found that statin use did not result in lower odds of cSDH recurrence, likely due to a dilution caused by the higher rate of patients on antithrombotic medications in the statin group.