Distribution of Serum Testosterone Concentrations in IBD Males and Associations With Inflammatory Bowel Disease Activity.

Background: An inverse relationship exists between inflammation and testosterone concentrations in non-inflammatory bowel disease (IBD) immune conditions but has not been objectively explored in the IBD male population. We aimed to characterize the distribution of testosterone concentrations in a cohort of males with IBD and identify any relationship between testosterone levels and disease activity.

Methods: We conducted a prospective cross-sectional study of male IBD patients. Demographics, disease characteristics, sex-hormone concentration, gonadotropins, C-reactive protein, fecal calprotectin, and patient-reported outcomes on quality of life and erectile function were collected. Relationships between disease activity, biomarkers, patient-reported outcome scores, and testosterone levels were analyzed using univariate and multivariate linear regression analyses.

Results: A total of 85 male IBD patients were included with a mean age 44 ± 14.1 years, of which 49.4% had Crohn's disease. Mean testosterone concentration was 15.4 ± 5.2 nmol/L and 17.6% had a serum testosterone <10.4 nmol/L. Active disease was associated with lower testosterone concentrations in univariate analysis (β ± SE = -0.25 ± -1.99, P = .02) but not in multivariate analysis (β -0.18 ± 1.75, P = .06). Testosterone concentrations were independently associated with sex hormone-binding globulin levels (β ± SE = 0.45 ± 0.04, P < .0001) and a younger age (β ± SE = -0.32 ± 0.04, P <.0001). Erectile function scores (5-item International Index of Erectile Function) were lower in IBD patients with a longer duration of disease (β ± SE = -0.24 ± 0.006, P = .04).

Conclusions: Lower testosterone concentrations in men with IBD may reflect confounding from other factors and are not independently associated with disease activity. Greater awareness and screening for sexual dysfunction should occur in males with IBD, particularly in those with a longer disease duration.