Alcohol intake and risk of pituitary adenoma

Background: The association between alcohol intake and incidence of pituitary adenoma has not been reported previously. We examined this association in three large, prospective cohort studies. Methods: Using data from the Nurses’ Health Study, Nurses’ Health Study II, and Health Professionals Follow-Up Study, we computed multivariable-adjusted hazard ratios (MVHR) and 95% confidence intervals (CI) for pituitary adenoma by levels of alcohol intake using Cox proportional hazards regression. Results: We identified 292 incident cases of pituitary adenoma (225 among women, 67 among men) among 235,973 participants with 6,548,732 person-years of follow-up. Compared with intake of ≤ 0.5 g/day, cumulative average alcohol intake in all categories was associated with reduced risk of pituitary adenoma (MVHR = 0.60, 95% CI 0.43–0.83 for 0.5–≤ 2 g/day, MVHR = 0.57, 95% CI 0.41–0.79 for > 2.0–≤ 8.0, MVHR = 0.70, 95% CI 0.47–1.04 for > 8.0–≤ 15.0, and MVHR = 0.51, 95% CI 0.32–0.83 for > 15.0 g/day). Significant inverse findings were present in women and were similar but non-significant in men. For specific alcoholic beverages, inverse associations were statistically significant for total wine (MVHR = 0.58, 95% CI 0.43–0.79 comparing 0.5–≤ 2 to ≤ 0.5 g/day), red wine (MVHR = 0.65, 95% CI 0.46–0.92 comparing 0.5–≤ 2 to ≤ 0.5 g/day), and white wine (MVHR = 0.72, 95% CI 0.53–0.97 comparing 0.5–≤ 2 to ≤ 0.5 g/day). Results were consistent using baseline intake, recent intake, and with an 8-year lag. Conclusion: In three prospective cohorts, compared to almost no consumption, alcohol consumption was associated with reduced risk of pituitary adenoma. Sensitivity analyses suggest that these results are unlikely to be the result of reverse causation or diagnostic bias.