Causal role of androgens in progression of HF in men questioned
MedWire News: Serum levels of androgens are not independently associated with increased mortality among men with heart failure (HF), researchers report.
The findings “argue against a causal role of androgens in the progression of HF,” say S Störk (University of Würzburg, Germany) and colleagues.
The researchers measured total and free serum testosterone, dehydroepiandrosterone sulfate (DHEAS), and sex hormone binding globulin (SHBG) in 191 men with HF, aged on average 64 years. Roughly half the men had reduced left ventricular function (ejection fraction ≤40%), and the proportions with New York Heart Association (NYHA) classes I–IV HF were 24%, 35%, 35%, and 6%, respectively.
They report in the journal Heart that 53 (28%) patients died during the median 859-day follow-up period.
DHEAS and free testosterone, but not total testosterone, levels were inversely associated with NYHA class.
Lower free testosterone and DHEAS levels, and higher SHBG levels were associated with mortality, at hazard ratios of 0.89 per 1-ng/dl increase in free testosterone (p=0.004), 0.95 per 10-µg/dl increase in DHEAS (p=0.058), and 1.18 per 10-nmol/l increase in SHBG level (p=0.006), after adjusting for age and NYHA class.
However, further adjustment for potential confounding factors not in the intermediate pathway abolished these associations. For free testosterone, these confounders were renal function, atrial fibrillation (AF), systolic blood pressure, C-reactive protein, N-terminal pro-brain natriuretic peptide (NT-proBNP), intake of diuretics, and cortisol. For DHEAS, they were renal function, AF, total cholesterol, NT-proBNP, intake of diuretics, and intake of beta blockers, and for SHBG they were renal function, AF, and intakes of ACE inhibitor, statin, and cortisol.
“Our results indicate that neither total testosterone nor calculated free testosterone, DHEAS, or SHBG represent independent predictors of mortality risk,” the authors remark. “Rather, androgens appear to co-vary with increasing age, worsening functional status, and severity of comorbidities.”
In a related editorial, Aikaterini Theodoraki and Pierre-Marc Bouloux (University College London, UK) commented that the cause of the high prevalence of hypogonadism in men with HF and its significance remains unclear, but point out that “different controlled studies have shown measurable benefits of testosterone supplementation in this setting.”
They concluded: “Further studies are needed to better characterize the role of anabolic hormones in this setting.”
MedWire (www.medwire-news.md) is an independent clinical news service provided by Current Medicine Group, a trading division of Springer Healthcare Limited. © Springer Healthcare Ltd; 2010
By Caroline Price