Takeaway
- Elevated serum levels of free testosterone were significantly associated with a lower risk of asthma and current wheeze in middle-aged and older British men and women.
- In addition, elevated levels were associated with a decreased risk of at least one asthma-related hospitalisation in women and with higher forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) in men.
Why this matters
- Findings suggest that free testosterone contributes to the pathogenesis of asthma in adults.
Study design
- A large population-based study of 256,419 British adults (age, 40-69 years; 123,921 women and 132,498 men) from the UK Biobank.
- Serum-free testosterone and physician-diagnosed asthma, wheeze, asthma hospitalisations and lung function were evaluated.
- Funding: None disclosed.
Key results
- Free testosterone levels above the first or lowest quartile (Q1) were significantly associated with a lower risk of asthma in both:
- women (adjusted OR [aOR] for Q4 vs Q1, 0.67; 95% CI, 0.64-0.71); and
- men (aOR for Q4 vs Q1, 0.87; 95% CI, 0.82-0.91).
- Free testosterone levels in Q4 vs Q1 were significantly associated with a lower risk of:
- current wheeze in women (aOR, 0.78; 95% CI, 0.71-0.87) and men with asthma (aOR , 0.86; 95% CI, 0.77-0.95); and
- ≥1 asthma hospitalisation in women with asthma (aOR, 0.73; 95% CI, 0.56-0.95).
- In men with asthma, free testosterone was positively associated with FEV1 (β, 26.0; 95% CI, 22.8-29.2) and FVC (β, 36.0; 95% CI, 32.3-39.8; P<.05 for both).
- Free testosterone was negatively and weakly linked with FVC in women with asthma (β, −4.3; 95% CI, −7.1 to −1.5; P<.05).
Limitations
- Temporal associations could not be examined in this cross-sectional design.
- Selection bias.
This clinical summary originally appeared on Univadis, part of the Medscape Professional Network.