OC55 - The role of obstructive sleep apnea syndrome and continuous positive airways pressure therapy in the functional hypogonadism of male patients with severe obesity

Background/Introduction To date, only a few studies have reported a correlation between severe OSA and hypogonadism in patients with obesity, regardless of body mass index (BMI). However, longitudinal studies exploring the role of continuous positive airways pressure (CPAP) on gonadal function are scanty. Purpose To investigate in a large cohort of males with severe/complicated obesity the role of the OSA in the diagnosis and severity of hypogonadism, adjusting for other known factors related to low testosterone in obesity; we also evaluated in a subset of patients the effects of CPAP therapy on hormonal status. Methods 204 male inpatients with complicated grade II (BMI ≥ 35 Kg/m2), or grade III (BMI ≥ 40 Kg/m2) obesity were included in the cross-sectional study. Polysomnography (or overnight oximetry during CPAP) and blood tests for inflammation indices, metabolic and hormonal profiles were performed during admission. “Decompensated OSA” was defined as Apnea/Hypopnea Index (AHI) in newly diagnosed, or Oxygen Desaturation Index (ODI) in treated patients, above 30 events/hour. The association of testosterone levels and age, Binge Eating Disorder, inflammation, diabetes, BMI, and “decompensated OSA” was investigated, and a multiple linear regression model was implemented to identify the independent factors correlated with functional hypogonadism in male patients with obesity. Lastly, a prospective longitudinal study of 14 newly diagnosed patients was performed to evaluate the effects of CPAP therapy on hormonal control after 3 months of treatment. Results 127/204 patients showed low testosterone levels (TT ≤10.4 nmol/L), associated with normal/low LH (<9.4 U/L) in 76.6% of them. BMI, type 2 diabetes mellitus (T2DM) and C-reactive Protein (CRP), as well as decompensated OSA were independently associated with testosterone levels (p-value 0.039, 0.006, 0.003 and 0.014 respectively). After 3 months of CPAP therapy, testosterone levels were higher (p-value 0.009) and ODI was significantly associated with such improvement, independently of BMI, at multivariate regression (p-value 0.04). Conclusion(s) decompensated OSA was found to correlate with low testosterone values in male patients with severe obesity. In addition, CPAP therapy was shown to improve testosterone levels independently of BMI changes.