High testosterone linked to reduced CV risk in elderly men
MedWire News: Elderly men with high serum testosterone levels have a significantly reduced risk for cardiovascular (CV) events, a study suggests.
This association remained significant after adjusting for traditional CV risk factors and excluding men with CV disease at baseline, report Åsa Tivesten (University of Gothenburg, Sweden) and colleagues in the Journal of the American College of Cardiology.
They used gas chromatography/mass spectrometry to analyze baseline testosterone levels in 2416 men aged 69-91 years, from the Osteoporotic Fractures in Men Swedish study.
Over a median follow-up period of 5.1 years, 485 participants experienced a major CV event, defined as a composite endpoint of CHD events (hospitalization for acute myocardial infarction, unstable angina or revascularization, or death from CHD) and cerebrovascular events (hospitalization for stroke or transient ischemic attack, or death from stroke).
Prespecified analyses revealed an inverse association between quartiles of testosterone level and sex hormone-binding globulin, a determinant of total testosterone level (SHBG), and any major CV event.
Men in the highest quartile of testosterone (≥550 ng/dl) were at a 30% lower risk for CV events than those in the pooled lower quartiles (p=0.002).
This association remained significant after excluding patients with a follow-up time of 2.6 years or less, in order to reduce the potential effect of subclinical or unrecognized disease.
The association between high testosterone and low risk was attenuated, but remained statistically significant, with a 23% reduction in risk at the highest levels after adjusting for traditional CV risk factors including age, body mass index, and hypertension.
In models that included both testosterone and SHBG, the association between SHBG and CV risk was no longer statistically significant, however, "suggesting that the covariation of SHBG with testosterone levels may explain some or all of its association with cardiometabolic risk," report the authors.
The investigators suggest a few potential mechanisms that could underlie the inverse association between testosterone level and CV events, including testosterone-conferred cardiometabolic risk and endothelial regeneration.
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 Piriya Mahendra