Increased Risk of Hypogonadal Symptoms in Shift Workers With Shift Work Sleep Disorder

To examine the association between shift work sleep disorder (SWSD), a primary circadian rhythm disorder characterized by excessive day-time sleepiness associated with shift work, and hypogonadal symptoms in shift workers.

Men presenting to an andrology clinic between July 2014 and June 2017 completed questionnaires assessing shift work schedule, SWSD risk, and hypogonadal symptoms ([quantitative] Androgen Deficiency in the Aging Male [qADAM, ADAM]). The impact of nonstandard shift work and SWSD on responses to qADAM and ADAM was assessed using ANOVA and linear regression.

About 24.1% (619/2571) of men worked nonstandard shifts. Of those, 196 (31.7%) were considered to have SWSD. Controlling for age, comorbidities, and testosterone (T) levels, nonstandard shift workers had qADAM scores 1.12 points lower than day-time workers (P <.01). Subgroup analysis of nonstandard shift workers showed that those with SWSD had qADAM scores 5.47 points lower than men without SWSD (P <.01). In this same subgroup analysis, SWSD was independently associated with lower T levels (mean decrease 100.4 ng/dL, P <.01) when controlling for age, comorbidities, and prior T supplementation.

Nonstandard shift workers with SWSD have even worse hypogonadal symptoms and lower T levels than day-time workers and nonstandard shift workers without SWSD. This suggests that poor sleep habits, as identified by SWSD, may contribute to the more severe hypogonadal symptoms seen in nonstandard shift workers.