Corticosteroids for preventing postherpetic neuralgia

Abstract

Background: Postherpetic neuralgia is a common serious complication of herpes zoster. Corticosteroids are anti-inflammatory and might be beneficial.

Objectives: To examine the efficacy of corticosteroids in preventing postherpetic neuralgia.

Search strategy: Search for randomised or quasi-randomised controlled trials for corticosteroids for preventing postherpetic neuralgia in MEDLINE (1950 to 2006), EMBASE (1980 to 2006), LILACS (1982 to 2005), the Chinese Biomedical Retrieval System (1978 to 2006) and the Cochrane Register of Controlled Trials (CENTRAL) (Cochrane Library Issue 3, 2006). Date of most recent search: September 2006.

Selection criteria: Types of studies: quasi-randomised or randomised controlled trials.

Types of participants: people of all ages with herpes zoster of all degrees of severity within seven days after onset. Types of interventions: all kinds of corticosteroids given by oral, intramuscular or intravenous routes during the acute stage (starting within one week of onset of the rash) compared with no treatment or placebo, but not with other treatments. We also included trials which compared corticosteroids plus routine treatment with placebo plus routine treatment. Types of outcome measures: Primary: the presence of postherpetic neuralgia six months after the onset of the acute herpetic rash. Secondary: pain severity measured by a validated visual analogue scale or numerical descriptive scale after three, six and 12 months; quality of life measured with the short form 36 questionnaire after six months; adverse events during or within two weeks after stopping treatment.

Data collection and analysis: Data were extracted by two independent reviewers.

Main results: Five trials were included with altogether 787 participants. All were randomised, double-blind, placebo-controlled parallel group studies. Our primary outcome measure was the presence of postherpetic neuralgia six months after the onset of the acute herpetic rash. There was no significant difference between the corticosteroid and control groups for the primary outcome (RR 1.27, 95% CI 0.20 to 7.97). There was also no significant difference between the corticosteroid plus antiviral agents and placebo plus antiviral agents groups for the primary outcome (RR 0.90, 95% CI 0.40 to 2.03). No included trials evaluated pain severity with a validated visual analogue scale or numerical descriptive scale and also no trials measured quality of life with the Short Form 36 questionnaire. Adverse events during or within two weeks after stopping treatment were reported by all five included trials, but after meta-analysis, there was no significant difference in any serious adverse event (death, acute cardiac insufficiency, rash dissemination, bacterial pneumonia or haematemesis) or non serious adverse event (dizziness, nausea, vomiting, hypertension or hyperglycaemia).

Authors' conclusions: There was insufficient evidence to conclude that corticosteroids are safe or effective in the prevention of postherpetic neuralgia. More randomised controlled trials with a greater number of participants are needed to determine reliably whether there is real benefit (or harm) from the use of corticosteroid therapy to prevent postherpetic neuralgia. Future trials should measure function and quality of life.