Current Knowledge/Study Rationale: The relationship between obesity, sleep apnea, and testosterone has been widely addressed in multiple studies, describing a negative correlation between polysomnographic parameters (apnea-hypopnea index, oxygen desaturation index and O2 nadir) and testosterone levels, but studies assessing this relationship in a nonobese population with obstructive sleep apnea (OSA) are still needed. Our research evaluated associations between total testosterone (TT) levels in nonobese patients with OSA and overnight polysomnography measurements.
Study Impact: The study demonstrated that, among nonobese men with OSA, being overweight may aggravate the reduction of TT associated with severe hypoxia measured by O2 nadir < 80% and oxygen desaturation index, regardless of apnea-hypopnea index. This association was only observed among normal-weight individuals older than 50 years as well. All normal-weight men with O 2 nadir ≥ 80% presented with normal TT levels.