Objective: To assess the effect of testosterone treatment on cardiac biomarkers in men with type 2 diabetes (T2D).
Design: Randomized double-blind, parallel, placebo-controlled trial.
Patients: Men aged 35-70 years with T2D and a total testosterone level ≤12·0 nmol/l (346 ng/dl) at high risk of cardiovascular events, median 10-year United Kingdom Prospective Diabetes Study (UKPDS) coronary heart disease (CHD) risk 21% (IQR 16%, 27%). Eighty-eight participants were randomly assigned to 40 weeks of intramuscular testosterone undecanoate (n = 45) or matching placebo (n = 43).
Main outcome measures: N-terminal pro B-type natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin T (hs-cTnT).
Result: Testosterone treatment reduced NT-proBNP (mean adjusted difference (MAD) in change over 40 weeks across the testosterone and placebo groups, -17·9 ng/l [95% CI -32·4, -3·5], P = 0·047), but did not change hs-cTnT (MAD, 0·41 ng/l (95% CI -0·56, 1·39), P = 0·62). Six men, three in each group experienced an adverse cardiac event, displaying already higher baseline NT-proBNP (P < 0·01) and hs-cTnT levels (P = 0·01). At baseline, 10-year UKPDS CHD risk was associated positively with NT-proBNP (τ = 0·21, P = 0·004) and hs-cTnT (τ = 0·23, P = 0·003) and inversely with testosterone (total testosterone τ = -0·18, P = 0·02, calculated free testosterone τ = -0·19, P = 0·01), but there was no significant association between testosterone and cardiac biomarkers (P > 0·05).
Conclusions: In this trial of men with T2D and high cardiovascular risk, testosterone treatment reduced NT-proBNP and did not change hs-cTnT. Further studies should determine whether men with increased cardiac biomarkers prior to testosterone therapy are at higher risk of testosterone treatment-associated adverse cardiac events.
© 2015 John Wiley & Sons Ltd.