Testosterone conversion blockade increases breathing stability in healthy men during NREM sleep.

Area of Science:

• Sleep Medicine
• Endocrinology
• Respiratory Physiology

Background:

• Male sex hormones, particularly testosterone, are implicated in gender differences in sleep apnea prevalence.
• The 5α-reductase pathway is crucial for converting testosterone to dihydrotestosterone, a more potent androgen.

Purpose of the Study:

• To investigate the role of testosterone in central sleep apnea (CSA) by examining the effects of finasteride, a 5α-reductase inhibitor.
• To determine if blocking testosterone conversion can enhance breathing stability during sleep.

Main Methods:

• A randomized, single-center study involving 14 healthy young males without sleep apnea.
• Participants received either oral finasteride or a sham treatment.
• Hypocapnia-induced central apneas were studied using noninvasive positive pressure ventilation during NREM sleep.
• Apneic threshold and carbon dioxide reserve were measured before and after treatment.

Main Results:

• Finasteride administration significantly decreased serum dihydrotestosterone levels.
• In the finasteride group, the apneic threshold was lowered, and the carbon dioxide reserve was increased, indicating enhanced breathing stability.
• No significant changes in ventilatory parameters were observed in the sham group.

Conclusions:

• Inhibiting testosterone action via the 5α-reductase pathway can improve breathing stability during sleep.
• This finding suggests a potential novel therapeutic strategy for central sleep apnea in specific patient populations.