Table 3

The association between chronic cough and phlegm and sex, smoking habits and socioeconomic status according to the presence of asthma

Chronic cough and phlegm
Without asthmaWith asthma
 Female versus male1.22 (1.10–1.36)**1.27 (1.04–1.55)*
Smoking habits
 Past smoker versus nonsmoker1.59 (1.35–1.86)**1.36 (1.04–1.79)*
 Current smoker (0–14 pack-yrs) versus nonsmoker2.56 (2.26–2.91)**1.85 (1.48–2.31)**
 Current smoker (≥15 pack-yrs) versus nonsmoker6.57 (5.70–7.58)**1.84 (1.31–2.58)**
Socioeconomic status
 Retired person, student, housewife versus manager, entrepreneur, businessman, clerk1.03 (0.89–1.18)1.19 (0.93–1.52)
 Unemployed person versus manager, entrepreneur, businessman, clerk1.24 (1.01–1.52)*1.63 (1.15–2.32)*
 Blue-collar worker versus manager, entrepreneur, businessman, clerk1.35 (1.18–1.54)**1.48 (1.14–1.92)*
  • All data are presented as adjusted OR (95% CI)

  • The ORs were calculated by multilevel binary response models with random intercept at the level of the centre and all predictor variables as fixed effects

  • The ORs were also adjusted for season of response, cumulative response rate and type of contact (telephone versus mail)

  • *: p<0.05, **p<0.001 value using the Wald test for the main factors