Higher serum testosterone and dihydrotestosterone, but not oestradiol, are independently associated with favourable indices of lung function in community-dwelling men.

Objectives: Lower circulating androgens and poorer lung function are associated with increased cardiovascular risk and mortality in men. The association between androgens and lung function is unclear. We tested the hypothesis that circulating testosterone (T) and its metabolites dihydrotestosterone (DHT) and oestradiol (E2) are differentially associated with lung function in men.

Methods: Early-morning serum T, DHT and E2 were assayed using mass spectrometry in 1768 community-dwelling men from Busselton, Western Australia. Forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were measured using spirometry. Linear regression models adjusting for age, height, smoking, exercise, body mass index, respiratory conditions and cardiovascular risk factors were used.

Results: Mean age was 50.1 ± 16·8 years. 16·0% were current smokers, 14·1% reported a history of asthma and 2·7% reported chronic obstructive pulmonary disease. Current smokers had higher T compared with never smokers (age-adjusted mean 14·5 vs 13·5 nmol/l, P = 0·002) and higher E2 (65·3 vs 60·1 pmol/l, P = 0·017). In fully adjusted analyses, T was associated with FEV1 (51 ml per 1 SD increase, P < 0·001) as was DHT (62 ml, P < 0·001), E2 was not (P = 0·926). Similar results were seen for FVC (T: 76 ml, P < 0·001; DHT: 65 ml, P < 0·001; E2 P = 0·664). Higher DHT was marginally associated with the ratio FEV1/FVC (0·3% per 1 SD increase, P = 0·047).

Conclusions: Both T and DHT were independently associated with higher FEV1 and FVC in predominantly middle-aged community-dwelling men. Androgens may contribute to, or be biomarkers for, better lung function in men. Further research is needed to clarify whether androgens preserve lung function in ageing men.