How Dexamethasone Affects Necessity for Surgical Intervention for Chronic Subdural Hematoma: Systematic Review and Meta-Analysis

The effectiveness of dexamethasone in managing chronic subdural hematoma (cSDH) patients remains uncertain although the drug is widely used in this condition. The present systematic review aims to understand the role of dexamethasone in reducing the need for surgery in cSDH patients. This study was conducted as per the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched the electronic databases of PubMed, SCOPUS, Cochrane Central Register of Controlled Trials (the Cochrane Library), and ScienceDirect with a predefined search strategy. The population consisted of cSDH patients older than 18 years and treated primarily with dexamethasone. The primary outcome was the need for surgery after dexamethasone therapy in cSDH patients. The meta-analysis of a group of patients was done with the invariance method to estimate the pooled odds of the requirement for surgery after dexamethasone therapy. In the studies with a one-to-one comparison of dexamethasone with placebo/observation, the Mantel-Haenszel statistics were used to determine the odds of surgery. The quality of the studies was assessed with the Newcastle-Ottawa scale (NOS) and the Cochrane risk of bias tool was used to assess the risk of bias in randomized studies. In total, 598 studies were obtained from the database search and after applying the inclusion and exclusion criteria, 10 studies were finally selected for the qualitative and quantitative synthesis. One of the 10 studies was a randomized controlled trial (RCT), while the rest were observational studies. There were 653 patients who received the primary dexamethasone therapy. Of these, 388 patients did not require surgery, while 256 needed surgeries after the therapy. The pooled estimate of requirement for surgery after dexamethasone therapy was 0.41, with a 95% confidence interval of 0.37 to 0.45. A meta-analysis of the one-to-one comparison from three included studies showed a higher need of surgery in the (comparator) placebo/observation group than in the dexamethasone group with odds ratio of 7.16 (95% confidence interval: 2.21-23.13, with p = 0.0001). In addition, we identified the gaps in literature, and the complications and mortality reported in the studies. Dexamethasone is effective in reducing the requirement for surgery in some selected cSDH cases, although many patients still require surgical intervention.