Abstract 1756: Marijuana use and serum testosterone concentrations among U.S. males

Abstract Background: Testicular germ cell tumors (TGCT) of young men can be histologically divided into nonseminomas and seminomas. Although TGCTs are thought to be hormonally-related, very few risk factors have been identified. Recently, however, marijuana use has been linked to risk of nonseminoma, which has peak incidence at a younger age (25 years) than does seminoma (35 years). Whether marijuana may be related to nonseminoma via an effect on testosterone concentrations is unknown. Thus, an analysis of U.S. males was conducted, using data from the 2011-2012 National Health and Nutrition Examination Survey (NHANES) of the NCHS, CDC. Methods: Data from 2409 males aged >20 years were included in the analysis. Serum total testosterone (T) concentrations, determined using liquid chromatography-tandem mass spectrometry, were log transformed for statistical analyses. Marijuana use was categorized as: never, current (use on at least one day in prior 30 days) and past (no use within prior 30 days). Regular use was defined as use at least once a month for > 1 year. Covariates included age, body mass index, race/ethnicity, cigarette smoking status and time of day of phlebotomy. Adjusted mean T concentrations were compared among marijuana use categories using weighted multiple linear regression analysis accounting for the complex sample design of NHANES. In addition to the overall analysis, models were stratified by age (20-30 years, >30 years). Results: Mean T concentration did not differ between never- and ever-users of marijuana (p = 0.62), but did differ between never-users and regular-users (2.56 ng/mL vs 2.59 ng/mL, p = 0.03) and between never-users and current-users (2.60 ng/mL, p = 0.007). In the analysis restricted to men >30 years of age, significant differences in mean T concentration were evident among never-users and current-users (2.55 ng/mL vs 2.60 ng/mL, p = 0.003). Significant differences were also seen with increasing duration of use as mean T concentrations were higher among men who used marijuana regularly for >5 years. In the analysis of men 20-30 years of age, no significant differences in mean T concentration by marijuana use were seen. Conclusion: These results suggest that regular use and current use of marijuana are associated with higher T concentrations among U.S. men, particularly men > 30 years of age. As nonseminomas are more common in younger men than in older men, the results may indicate that the association between marijuana use and nonseminoma is not due to an effect of marijuana on circulating T concentrations. Citation Format: Katherine A. McGlynn. Marijuana use and serum testosterone concentrations among U.S. males. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1756.