Oral Corticosteroid Therapy for Preventing Postherpetic Neuralgia: A Systematic Review and Meta-analysis

Abstract

The purpose of this systematic review was to examine the efficacy of oral corticosteroids for prevention of postherpetic neuralgia (PHN). Randomized controlled trials of patients suffering from herpes zoster comparing corticosteroids to control therapy (placebo or carbamazepine) or acyclovir were included. Three electronic databases (MEDLINE via PubMed, Web of Science and The Cochrane Library) were searched. Two authors assessed all eligible studies for risk of bias. Ninety-one references were found. After applying inclusion/exclusion criteria 7 studies were eligible for this systematic review. All 7 studies were at high risk of bias. Corticosteroids, rather than carbamazepine, protected the patients against PHN (Relative Risk [RR] = 0.543, 95% CI 0.087 to 3.376, p=0.512), however the results were not statistically significant. Additionally, a second meta-analysis showed that the use of corticosteroids does not prevent PHN compared to the use of a placebo (RR=0.990, 95% CI 0.092 to 10.663, p=0.994). Mild and reversible side effects were reported in patients taking only corticosteroids; two serious cardiovascular events were reported in the patients prescribed acyclovir and corticosteroid, though those two events were probably unrelated to the therapy. Individual studies reported quality of life improvements and reduction in the incidence and severity of pain with the addition of prednisone to acyclovir therapy; however the heterogeneity of the outcomes and comparison group prevented from performing meta-analyses on these outcomes. Due to the low number of studies, high risk of bias, heterogeneity of the outcomes and comparison groups, the evidence this systematic review provided was of low quality.