Obesity may be the common pathway for sleep-disordered breathing in women with polycystic ovary syndrome

Abstract

ObjectivePolycystic ovary syndrome (PCOS) is one of the most common endocrinological disorders in women of reproductive age, and is characterized by hyperandrogenism. It is associated with long-term metabolic dysfunctions including sleep-disordered breathing (SDB). We hypothesized that the increased prevalence of SDB in PCOS results from raised testosterone levels. MethodsThis was a prospective, cross-sectional, case–control study in which 50 case patients with untreated PCOS and 100 control subjects were included. All the case patients and control subjects went through a detailed clinical, biochemical, and hormonal evaluation. Overnight polysomnography was performed in all case patients and the snorers (16 of 100) in the control group. ResultsSDB was seen in 66% of the case patients and in 4% of control group with (odds ratio [OR] = 46.5, 95% confidence interval [CI] = 14.6–148.4; p < 0.001). After adjustment for body mass index (BMI) and waist circumference (WC), the difference was not significant (p = 0.993 and p = 0.931, respectively). The SDB patients with PCOS showed significantly higher respiratory distress index (RDI) values than SDB patients in the control group (22.5 ± 21.5 vs 9.0 ± 5.6, p = 0.01). On the Epworth Sleepiness Scale the PCOS case patients reported feeling more sleepy than did the control subjects (12.5 ± 3.2 vs 9.32 ± 1.7, p < 0.001). Free testosterone levels were also significantly higher in the PCOS group than in the control subjects (2.95 ± 3.44 vs 1.5 ± 1.0, p < 0.001). There was a significant correlation between free testosterone level and RDI values (r = 0.377; p = 0.007), WC (r = 0.315; p = 0.026), and BMI (r = 0.398; p = 0.004). A significant correlation of WC (r = 0.551; p < 0.001) and BMI (r = 0.572; p < 0.001) was observed with RDI. ConclusionTestosterone-induced obesity is probably the common pathway for the development of SDB in PCOS.