Androgens regulate male development, virilisation and body composition, and are biomarkers for metabolic and cardiovascular health-related outcomes. Their influence on lung function is unclear. We tested the hypothesis that circulating testosterone (T) and its metabolites dihydrotestosterone (DHT) and estradiol (E2) are differentially associated with lung function in community-dwelling men.
Design, participants and measurements:
We conducted a cross-sectional analysis of 1,768 men from the Busselton Health Survey in Western Australia. Early morning serum concentrations of T, DHT and E2 were assayed using liquid chromatography-tandem mass spectrometry. Sex hormone-binding globulin (SHBG) and luteinising hormone (LH) were measured by immunoassay. Forced expiratory volume (1 second) was measured, and expressed as percent predicted value (PPFEV1).
Men were aged (mean±SD) 50.1±16.8 years. 15.9% were current smokers, 14.1% reported a history of asthma, 2.7% chronic obstructive pulmonary disease (COPD) and 17% cardiovascular disease (CVD). Current smokers had higher T concentrations compared with never smokers (14.5 vs 13.5 nmol/L, p=0.002), comparable DHT (1.84 vs 1.74 nmol/L, p=0.057) and higher E2 (65.3 vs 60.1 pmol/L, p=0.017). Mean PPFEV1 increased across deciles of T and DHT, and decreased across deciles of LH with no trends apparent for E2 or SHBG. In regression analyses adjusted for age, smoking, asthma, bronchitis, recent wheeze, cough, COPD, exercise, BMI and cardiovascular risk factors, T was associated with PPFEV1 (1.4% increase per 1 SD increase in hormone concentration, p<0.001) as was DHT (1.9%, p<0.001). E2 was not associated with PPFEV1 (0.04%, p=0.92).
Both T and DHT were independently associated with PPFEV1 in predominantly middle-aged community-dwelling men, while E2 was not associated. Androgens may contribute to, or be biomarkers for, better lung function in men distinct from the influences of smoking or COPD. Further research is needed to clarify whether androgens play a role in preserving lung function in ageing men.