A meta-analysis of active smoking and risk of meningioma

INTRODUCTION: Cigarette smoking has been hypothesized to be a risk factor for meningioma. However, the results of studies exploring the relationship between smoking exposure and the occurrence of meningioma are inconsistent. METHODS: A search of PubMed, Medline, Embase, and Science Direct (up to June 2020) databases was performed. Two authors independently extracted the data. The Newcastle–Ottawa Scale was employed for judging the quality of articles. A random-effects model was utilized for meta-analysis. Association analysis between smoking and meningioma was based on the adjusted RR and the 95% CI, as reported by eligible studies. Subgroup and sensitivity analyses were performed and publication bias was assessed. Subgroup analysis was conducted by geographical region, study design, sex, study quality, and adjustments of RR score. Begg’s and Egger’s tests were employed for detecting publication bias. RESULTS: Twelve articles, including 2 cohort studies and 10 case–control studies, and a total of 1210167 participants were identified. The pooled relative risk (RR) with 95% confidence interval (95% CI) implied that smoking was not associated with increased risk of meningioma in men and women combined (RR=1.09; 95% CI: 0.90–1.33). From the sex-stratified subgroup analysis, the risk of meningioma was significant in men (RR=1.42; 95% CI: 1.16–1.74). Risk of meningioma in women did not remain significant (RR=0.92; 95% CI: 0.73–1.16). There was a high heterogeneity in the results (I(2)=58.4%, p=0.002). Sensitivity analyses showed stable results and there was no evidence of publication bias. CONCLUSIONS: Cigarette smoking is not associated with a significantly increased risk of meningioma in the whole population, but there is a positive association in men but not in women.