Table 2.
Association of risk factors with severe adult-onset asthma by using a question-based definition of severe asthma (Sev-Q)
| Model 1 Univariate regression model |
Model 2 Multiple regression model n = 1173 |
|||
|---|---|---|---|---|
| OR1 (95% CI) | p1 | OR2 (95% CI) | p2 | |
| Male sex | ||||
|
No Yes |
1 2.12 (1.41–3.20) |
< .001 |
1 1.96 (1.16–3.30) |
.011 |
| Age1 | ||||
| 1.033 (1.02–1.05) | < .001 | 1.002 (0.98–1.03) | .88 | |
| BMI1 | ||||
| 1.010 (0.97–1.06) | .66 | Not entered | ||
| Baccalaureate/secondary school | ||||
|
No Yes |
1 0.50 (0.31–0.82) |
.006 |
1 0.88 (0.48–1.65) |
.70 |
| Professional training | ||||
|
No Yes |
1 0.51 (0.33–0.80) |
.003 |
1 0.62 (0.36–1.05) |
.074 |
| Ever smokers | ||||
|
No Yes |
1 2.10 (1.32–3.32) |
.002 |
1 1.98 (1.11–3.52) |
.020 |
| 1st child | ||||
|
No Yes |
1 0.69 (0.42–1.12) |
.14 | Not entered2 | |
| ≥ 2 siblings | ||||
|
No Yes |
1 2.66 (1.37–5.20) |
.004 |
1 2.51 (1.17–5.41) |
.018 |
| Growing up in the countryside/on a farm | ||||
|
No Yes |
1 1.29 (0.77–2.17) |
.34 | Not entered | |
| Severe childhood infections2 | ||||
|
No Yes |
1 0.60 (0.32–1.15) |
.13 |
1 0.55 (0.26–1.14) |
.11 |
| Parental smoking | ||||
|
No Yes |
1 1.05 (0.70–1.58) |
.82 | Not entered | |
| Parental asthma and/or allergy | ||||
|
No Yes |
1 0.76 (0.48–1.19) |
.22 | Not entered | |
| NERD | ||||
|
No Yes |
1 2.13 (1.25–3.63) |
.005 |
1 3.29 (1.75–6.19) |
< .001 |
| CRSwNP | ||||
|
No Yes |
1 0.57 (0.26–1.26) |
.17 |
1 0.54 (0.22–1.30) |
.17 |
| ≥ 1 other disease 3 | ||||
|
No Yes |
1 2.97 (1.67–5.28) |
< .001 |
1 2.68 (1.35–5.31) |
.005 |
| ≥ 1 other allergic disease (AR/AC/AD) | ||||
|
No Yes |
1 0.82 (0.54–1.25) |
.36 | Not entered |
Bold values denote statistical significance at the p < 0.05 level
Model 1 = univariate analysis. Model 2 = multivariable analysis by the eleven variables that were associated at the p < 0.2 level in Model 1. NERD = patient-reported NSAID-exacerbated respiratory disease; CRSwNP = chronic rhinosinusitis with nasal polyps; AR = allergic rhinitis; AC = allergic rhinoconjunctivitis, AD = atopic dermatitis. 1continuous variables. 2The variables “1st child” and “ ≥ 2 siblings” correlated (p < 0.01, r = − 0.42, by Pearson’s correlation test); hence, to avoid multicollinearity, only the statistically significant variable “ ≥ 2 siblings” was added into the multivariable model. 2pneumonia before or during school age and/or hospitalization due to infection at ≤ 3 years of age. 3Hypertension (n = 298), coronary artery disease (n = 120), rheumatoid arthritis (n = 60), psychiatric disorder (n = 86), diabetes (n = 54), glaucoma (n = 49), back disease (n = 367), arthritis (n = 244), empyema (n = 106), other chronic disease(s) except chronic bronchitis/bronchiectasis (n = 449). Education level = baccalaureate/secondary versus primary school; professional training = completed professional college/university/courses/trade school versus no professional training. OR = odds ratio. CI = confidence interval. Severe asthma (Sev-Q) was defined as self-reported severe asthma and asthma symptoms causing much harm and regular impairment and ≥ 1 oral corticosteroid course/year or regular oral corticosteroids and/or waking up in the night due to asthma symptoms/wheezing ≥ a few times/month