Alcohol intake and risk of glioma: results from three prospective cohort studies

Purpose: The association between alcohol intake and glioma remains unclear. We evaluated the association between alcohol intake and incidence of glioma in three large, prospective cohort studies with repeated alcohol assessments. Methods: We harnessed data from three studies with repeat alcohol assessment to compute hazard ratios (HR) and 95% confidence intervals (CI) for glioma by overall alcohol intake and intake from specific beverages using Cox proportional hazards regression, adjusted for age, cohort, body mass index, smoking status, and caloric intake. Analyses were conducted separately for glioma overall and for glioblastoma (GBM). Results: We confirmed 554 incident glioma cases (362 GBM) among 237,505 participants with 6,216,378 person-years of follow up. Cumulative average alcohol intake was associated with reduced risk of glioma (HR = 0.75, 95%CI:0.56–0.99 comparing > 8–15 to ≤ 0.5 g/d; HR = 0.71, 95%CI:0.53–0.96 comparing > 15 g/d to ≤ 0.5 g/d). When stratified by sex, for the same comparisons, the HRs for men were 0.57 (95%CI:0.36–0.89) and 0.79 (0.53–1.16), and for women 0.90 (95%CI:0.62–1.30) and 0.62, 95%CI:0.39–0.97. Results were consistent when examining cumulative average, baseline, and recent intake, and with a 4 year lag. Conclusion: These results provide evidence against a positive association between alcohol intake and glioma risk. Alcohol intake was associated with reduced risk of glioma in both men and women.