Endocrine Abstracts

BACKGROUND: We have previously shown that men with coronary artery disease (CAD) have lower serum bioavailable testosterone levels than men with normal coronary arteries and this may have detrimental effects in coronary disease. It has been suggested that low androgen levels in men with CAD could be accounted for by the high prevalence of statin therapy and other factors such as smoking. We investigated the effects of statin therapy and smoking on testosterone in men with CAD.

METHODS: 500 men with CAD ( >70% stenosis, one or more coronary artery at angiography) were enrolled in a cross-sectional study. Blood was collected between 8 and 10 am, total and bioavailable testosterone (TT and BT) and SHBG were measured. Age and body mass index (BMI) were determined and history taken regarding smoking and statin therapy. Data were analysed using Pearson's correlation and Student's t tests and presented as mean(SD)

RESULTS: Mean age was 61.2(8.9)yrs, TT; 14.7(6.4)nM, BT; 4.4(2.5)nM. BT but not TT correlated inversely with age (r=-0.21, p<0.001) and serum SHBG increased with age (r=0.30, p<0.001). Subjects taking statins (n=363) were significantly younger (60.4(8.5)yrs v 63.3(9.5)yrs, p<0.001) and had lower TT (14.3(5.7)nM v 15.7(7.9)nM, p<0.05) and SHBG (44.5(24.8)mM v 51.2(28.6)mM, p<0.05) levels than non-statin-takers (n=137). Serum BT levels did not differ between the two groups (4.3(2.1)nM v 4.5(3.3)nM, p=0.5). Smokers had higher levels of TT (16.0(5.3)nM v 14.5(6.6)nM, p<0.05) but similar levels of BT and SHBG.

DISCUSSION: In men with CAD, statin use is associated with lower levels of TT and SHBG while smokers had higher levels of TT. However, the more important BT level was not affected by either factor. It appears that the low levels of testosterone observed in men with CAD are not accounted for by the high prevalence of statin use in this population.