Efficacy of Continuous Positive Airway Pressure on Testosterone in Men with Obstructive Sleep Apnea: A Meta-Analysis

OBJECTIVE To evaluate the efficacy of continuous positive airway pressure (CPAP) on serum testosterone in men with obstructive sleep apnea (OSA). METHODS Two reviewers independently searched PubMed, Cochrane library, Embase and Web of Science before June 2014. Information on characteristics of subjects, study design, pre- and post-CPAP treatment of serum total testosterone, free testosterone and sexual hormone blinding protein (SHBG) was extracted for analysis. RESULTS A total of 7 studies with 9 cohorts that included 232 men were pooled into meta-analysis. There was no change of total testosterone levels before and after CPAP treatment in OSA men (standardized mean difference (SMD) = -0.14, 95%CI: -0.63 to 0.34, z = 0.59, p = 0.558), even subdivided by CPAP therapeutic duration (>3 months). Meanwhile, no significant differences in free testosterone and SHBG were detected after CPAP treatment (SMD =  0.16, 95%CI: -0.09 to 0.40, z = 1.25, p = 0.211 and SMD = -0.58, 95%CI: -1.30 to 0.14, z = 1.59, p = 0.112, respectively). CONCLUSION CPAP has no influence on testosterone levels in men with OSA, further large-scale, well-design interventional investigation is needed.