Mater Misericordiae Hospital, Raymond Terrace, South Brisbane, BrisbaneQLD 4101, Australia
* Correspondence to: Tel: +61 7 3840 8111; Fax: +61 7 3840 1543
E-mail address: amorton{at}mater.org.au
Received 3 June 2003; revised 18 July 2003; accepted 31 July 2003
Sir,
I read with interest the recent paper by Pugh et al. on the acute haemodynamic effects of testosterone in patients with cardiac failure, with the greatest benefit seen in those with the lowest androgen levels.1I note that a larger study assessing the safety and efficacy of testosterone therapy for heart failure is in progress. I think it will be important to exclude obstructive sleep apnoea (OSA) in this group of patients prior to a long-term trial of androgen therapy, and it is possible that OSA is the cause of hormonal deficiencies in patients with cardiomyopathy. An assessment of hormonal profiles in idiopathic dilated cardiomyopathy demonstrated significant reductions in growth hormone, insulin-like growth factor I (IGF-1), and testosterone, which was attributed to chronic disease.2Obstructive sleep apnoea has been demonstrated in up to 37% of patients with cardiac failure.3OSA is associated with reduced pituitary-gonadal secretion as well as lower levels of basal and GH-stimulated IGF-1.4,5This neuroendocrine dysfunction is reversible with continuous positive airways pressure treatment (CPAP) and with uvulopalatopharyngoplasty. Continuous positive airways pressure treatment of patients with heart failure and OSA improves left ventricular ejection fraction and reduces systolic blood pressure.3Exclusion of OSA prior to testosterone administration is critical as androgen administration may aggravate or precipitate the condition, possibly through an increase in upper airwaycollapsibility during sleep. This has the potential to cause further deterioration in cardiac function. Finally the effects of spironolactone in blocking androgen action at the receptor level are an additional consideration in assessingpossible benefits of androgens in cardiomyopathy.
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