Obstructive Sleep Apnea and Testosterone Deficiency

Abstract

Obstructive sleep apnea (OSA) is a common disorder characterized by intermittent hypoxia and sleep fragmentation. OSA in middle-aged men is often associated with decreased testosterone secretion, together with obesity and aging. Although OSA treatment does not reliably increase testosterone levels in most studies, OSA treatment with testosterone replacement therapy (TRT) may not only improve hypogonadism, but can also alleviate erectile/sexual dysfunction. However, because TRT may exacerbate OSA in some patients, patients should be asked about OSA symptoms before and after starting TRT. Furthermore, TRT should probably be avoided in patients with severe untreated OSA.

Keywords: Continuous positive airway pressure; Erectile dysfunction; Sexual dysfunction, physiological; Sleep apnea, obstructive; Testosterone.

Fig. 1. Potential mechanisms linking obstructive sleep apnea (OSA) and obesity to low testosterone. A bidirectional relationship between testosterone and obesity or OSA is shown. While OSA and obesity lead to lower testosterone, low testosterone promotes obesity and affects sleep quality. REM: rapid eye movement, SHBG: sex hormone binding globulin, GnRH: Gonadotropin-releasing hormone, LH: luteinizing hormone.

Fig. 2. The plausible mechanisms by which testosterone replacement therapy (TRT) worsens obstructive sleep apnea (OSA). TRT aggravates OSA by several physiologic mechanisms including neuromuscular changes to the airways, changes in metabolic requirements, and changes in the physiologic response to hypoxia and hypercapnia.