Effects of testosterone therapy on sleep and breathing in obese men with severe obstructive sleep apnoea: a randomized placebo-controlled trial

Study objectives High doses of short-term testosterone have been shown to acutely worsen sleep-disordered breathing in men with obstructive sleep apnoea (OSA). The effects of lower, near-conventional doses of testosterone in obese men with OSA may differ over the longer term but have not been systematically studied. We assessed sleep and breathing effects of near-conventional testosterone treatment as an adjunct to weight loss in obese men with severe OSA. Design An 18-week randomized, double-blind, placebo-controlled, parallel group trial in 67 men. Interventions All subjects were placed on a hypocaloric diet and then received intramuscular injections of 1000mg testosterone undecanoate or placebo at 0, 6 and 12 similar to weeks. Measurements and Results Sleep and breathing were measured by nocturnal polysomnography at 0, 7 and 18weeks. Testosterone, compared to placebo, worsened the oxygen desaturation index (ODI) by 10.3events/h (95%CI, 0.819.8events/h; P=0.03) and nocturnal hypoxaemia (sleep time with oxygen saturation <90%, SpO2T90%) by 6.1% (95%CI, 1.510.6; P=0.01) at 7weeks. Testosterone therapy did not alter ODI (4.5, -5.4 to 14.4events/h; P=0.36) or SpO2T90% at 18weeks (2.9, -1.97.7%; P=0.23) compared to placebo. The testosterone treatment effects on ODI and SpO2T90% were not influenced by baseline testosterone concentrations (testosterone by treatment interactions, all P > 0.35). Blood testosterone concentrations did not correlate with ODI or SpO2T90% (all P > 0.19). Conclusions Testosterone therapy in obese men with severe OSA mildly worsens sleep-disordered breathing in a time-limited manner, irrespective of initial testosterone concentrations. This time-dependency was not related to testosterone concentrations. Trial similar to Registration www.anzctr.org.au Identifier: ACTRN1260-6000404527.