Meta-analysis of clinical studies with betahistine in Ménière's disease and vestibular vertigo.

We present a meta-analysis of 12 double-blind, randomized, placebo-controlled clinical studies with betahistine in patients suffering from vestibular vertigo or Ménière's disease, based on both published and unpublished data. The clinical endpoint we used was the investigator's overall opinion on the response to treatment of the vertigo symptoms, after at least 1 month of treatment. We introduce a new effect parameter, the odds of a favorable treatment outcome, with the odds ratio as measure to compare the responses of betahistine and placebo patients. For each study a separate odds ratio was estimated (the study-specific odds ratio). All but one of the study-specific odds ratios were >1.0, meaning that with the new effect parameter there was evidence of an effect of betahistine on vertigo symptoms in 11 of the 12 studies. Four of the 12 studies showed a statistically significant effect in favor of betahistine compared to placebo. The meta-analytical (i.e., average) odds ratio was 2.58 (95% confidence interval 1.67-3.99), a statistically significant result. This means that on average, the likelihood of a favorable outcome is almost two times higher for patients treated with betahistine than for placebo-treated patients. Sub-analyses conducted for patients with Ménière's disease on one hand and with vestibular vertigo on the other hand also yielded statistically significant results. For Ménière's disease, the meta-analytical odds ratio was 3.37 (95% CI 2.14-5.29); for vestibular vertigo, the odds ratio was 2.23 (95% CI 1.20-4.14). Our meta-analysis supports the therapeutic benefit of betahistine on vertiginous symptoms in both Ménière's disease and vestibular vertigo.