- Adult-onset asthma was positively associated with the number of allergic diseases including rhinitis, conjunctivitis, and dermatitis.
- However, this association decreased with increasing age.
Why this matters
- Few previous studies have addressed cohort- or age effect of the coexisting allergic diseases and asthma.
- This cross-sectional population-based case-control study evaluated the association between allergic multimorbidity and adult-onset asthma in 1118 adults with asthma and 1772 sex-, age- and living region-matched control patients.
- Funding: Finnish Medical Foundation and others.
- Allergic rhinitis (AR), allergic conjunctivitis (AC) and atopic dermatitis (AD) were reported in 50.2%, 39.6% and 33.8% of patients with asthma, respectively vs 26.1%, 20.0%, and 23.5% in controls, respectively.
- Compared with non-allergic disease, risk for adult-onset asthma was increased with:
- AR (adjusted OR [aOR], 1.95; 95% CI, 1.52-2.49),
- AC (aOR, 2.87; 95% CI, 2.19-3.77) and
- AD (aOR, 4.26; 95% CI, 3.07-5.90).
- Risk for adult-onset asthma associated with ≥1 allergic multimorbidity decreased with increasing age:
- 50-62 years (aOR, 2.44; 95% CI, 1.74-3.42) and
- >62 years (aOR, 1.68; 95% CI, 1.04-2.71; Pinteraction=.002 for all).
- Risk of residual confounding.