Figures
- Fig. 1—
Selection of the study population for the European Community Respiratory Health Survey (ECRHS) II socioeconomic status, asthma and chronic bronchitis study. SOB: shortness of breath.
Tables
- Table 1—
Characteristics of participants in the European Community Respiratory Health Survey II(1999–2001)#
Individual variables Subjects Range by centre % Sex Male 3412 (49.0) 41.3–54.4 Female 3553 (51.0) 45.6–58.7 Age yrs 43.0±7.1 39.2–46.7 BMI kg·m−2 <20 390 (5.7) 1.1–12.3 ≥20–<25 3096 (45.6) 31.3–60.9 ≥25–<30 2429 (35.8) 25.8–45.3 ≥30 879 (12.9) 3.1–29.8 Family history of asthma 808 (11.6) 5.7–19.2 Smoking status Never-smoker 2927 (42.0) 30.2–60.7 Former smoker 1945 (27.9) 6.5–40.7 Current smoker 2027 (29.1) 11.9–48.2 Exposure to ETS 2637 (38.0) 18.9–78.2 Siblings 0 690 (9.9) 0.9–21.3 1 2121 (30.5) 12.3–48.7 ≥2 4134 (59.5) 31.4–79.8 Respiratory infections before 5 yrs of age 689 (9.9) 2.2–16.3 Rhinitis 2051 (29.5) 11.1–43.0 High occupational exposure to biological or mineral dust, gas or fumes 991 (14.6) 5.0–27.6 Mould or mildew in home in previous 12 months 1166 (16.7) 2.2–40.7 Outcome variables Asthma 725 (10.4) 4.9–15.9 With atopy 372 (5.3) 1.3–11.8 Without atopy 353 (5.1) 2.2–9.7 Atopy without asthma 1646 (23.6) 13.4–33.9 No asthma nor atopy 4594 (66.0) 52.6–81.7 Chronic bronchitis¶ 247 (3.0) 0.0–8.5 Asthma score 0.66±1.2 0.36–0.96 Socioeconomic status measures Occupational class+ I 2096 (30.1) 15.1–49.7 II 1246 (17.9) 7.5–28.2 III 1791 (25.7) 15.5–40.2 IV 695 (10.0) 2.2–18.5 V 655 (9.4) 2.8–19.0 VI 482 (6.9) 1.3–17.5 Educational level (country-specific tertiles) High 1883 (28.4) 17.8–37.3 Medium 2101 (31.7) 10.9–48.0 Low 2650 (39.9) 29.5–63.8 Data are presented as n (%) or mean±sd, unless otherwise stated. BMI: body mass index; ETS: environmental tobacco smoke. #: only subjects with serum immunoglobulin E measurements were included (n = 6,965); ¶: chronic bronchitis category (n = 7,915); +: I for managers and professionals, II for technicians and associate professionals, III for other nonmanual workers, IV for skilled manual workers, V for semi-skilled/unskilled manual workers and VI for unclassifiable/unknown.
- Table 2—
Prevalence odds ratios(POR) of asthma (with or without atopy) and chronic bronchitis in European Community Respiratory Health Survey II participants by occupational class and education level
POR (95%CI) Asthma Asthma with atopy Asthma without atopy Chronic bronchitis Subjects n 6965# 2018 4947 7915¶ Minimally adjusted+ Occupational class§ Iƒ 1 1 1 1 II 1.16 (0.91–1.47) 1.15 (0.82–1.60) 1.10 (0.77–1.57) 1.43 (0.94–2.17) III 1.26 (1.01–1.56) 1.15 (0.83–1.60) 1.44 (1.06–1.95) 1.71 (1.17–2.51) IV–V 1.07 (0.83–1.36) 0.91 (0.63–1.30) 1.26 (0.89–1.79) 1.84 (1.23–2.74) VI 1.37 (1.00–1.88) 1.07 (0.67–1.72) 1.55 (1.00–2.41) 1.62 (0.97–2.69) Educational level Highƒ 1 1 1 1 Medium 1.02 (0.82–1.26) 0.74 (0.54–1.00) 1.39 (1.01–1.93) 1.54 (1.05–2.25) Low 1.19 (0.93–1.43) 0.93 (0.70–1.25) 1.70 (1.26–2.29) 1.93 (1.35–2.76) Fully adjusted## Occupational class§ Iƒ 1 1 1 1 II 1.13 (0.88–1.42) 1.08 (0.75–1.54) 1.13 (0.78–1.65) 1.43 (0.91–2.23 III 1.25 (0.99–1.57) 1.22 (0.87–1.72) 1.34 (0.97–1.85) 1.53 (1.01–2.34) IV–V 1.08 (0.78–1.48) 0.91 (0.57–1.46) 1.20 (0.77–1.88) 1.66 (0.96–2.87) VI 1.25 (0.84–1.86) 1.16 (0.63–2.14) 1.28 (0.75–2.19) 1.24 (0.56–2.75) Educational level Highƒ 1 1 1 1 Medium 1.02 (0.81–1.28) 0.75 (0.53–1.05) 1.40 (1.00–1.97) 1.59 (1.04–2.42) Low 1.20 (0.95–1.52) 1.10 (0.79–1.52) 1.55 (1.18–2.14) 1.66 (1.10–2.50) CI: confidence interval. #: Only subjects with serum immunoglobulin E measurements were included (except bronchitis category); ¶: excludes Tartu (Estonia) centre; +: for age, sex and centre; §: I for managers and professionals, II for technicians and associate professionals, III for other nonmanual workers, IV for skilled manual workers, V for semi-skilled/unskilled manual workers and VI for unclassifiable/unknown; ƒ: reference category; ##: for age, sex, country, body mass index, family history of asthma, number of siblings, exposure to environmental tobacco smoke, smoking status, respiratory infections before 5 yrs of age, mould or mildew in the home in the previous 12 months, rhinitis and high occupational exposure to pollutants.
- Table 3—
Cumulative incidence of respiratory symptoms and sensitisation and asthma score by occupational class and education level between European Community Respiratory Health Survey I(1991–1992) and II (1999–2001)#
Variable Occupational class¶ Education I II III IV–V VI p-value+ High Medium Low p-value+ Asthma symptom Breathless while wheezing in previous 12 months 1.4 1.1 1.4 1.6 0.5 <0.001 1.5 1.6 2.9 0.004 Waking with chest tightness in previous 12 months 2.5 1.6 2.3 1.8 0.8 0.306 2.3 2.5 3.9 0.032 Attack of shortness of breath at rest in previous 12 months 0.9 0.6 1.1 0.6 0.4 0.141 1.0 1.0 1.6 0.248 Attack of shortness of breath after exercise in previous 12 months 3.9 2.5 4.5 3.2 1.2 0.001 3.6 4.2 7.3 <0.001 Waking due to attack of shortness of breath in previous 12 months 0.9 0.7 1.0 0.6 0.4 0.071 0.9 1.3 1.6 0.345 Asthma ever 1.0 0.8 1.0 0.7 0.3 0.553 1.1 1.2 1.7 0.428 Asthma score mean 0.24 0.36 0.36 0.35 0.38 <0.001§ 0.28 0.29 0.38 <0.001§ Asthma 1.3 1.0 1.5 0.9 0.5 0.062 1.2 1.7 2.4 0.087 Other symptoms Bronchitis 0.2 0.3 0.4 0.3 0.2 0.148 0.2 0.5 0.7 0.008 Sensitisation Dermatophagoides pteronyssinus 4.4 2.5 2.8 2.8 1.1 0.009 3.9 4.6 4.6 0.028 Cat 2.1 1.5 1.5 1.2 0.4 0.186 2.0 2.2 2.3 0.308 Grass 4.4 2.9 3.4 2.7 0.9 0.265 4.5 4.5 5.0 0.034 Cladosporium herbarium 0.3 0.1 0.1 0.2 0.04 0.509 0.2 0.2 0.3 0.592 Data are presented as % of new cases, unless otherwise stated. #: Only subjects with serum immunoglobulin E measurements were included (except bronchitis category); ¶: I for managers and professionals, II for technicians and associate professionals, III for other nonmanual workes, IV for skilled manual workers, V for semi-skilled/unskilled manual workers and VI for unclassifiable/unknown; +: from Chi-squared test for association with categorical variables; §: p-value from likelihood ratio test for asthma score.
- Table 4—
Cumulative incidence risk ratios(RR) of asthma (with or without atopy) bronchitis and asthma score for European Community Respiratory Health Survey II participants by occupational class and education level
RR (95% CI) IRR (95% CI) Asthma Asthma with atopy Asthma without atopy Bronchitis Asthma score Subjects n 5645# 1406 4239 6455¶ 5924+ Minimally adjusted§ Occupational classƒ I## 1 1 1 1 1 II 1.23 (0.90–1.67) 1.47 (0.88–2.47) 1.16 (0.74–1.81) 1.72 (0.87–3.41) 1.36 (1.12–1.64) III 1.18 (0.89–1.57) 1.13 (0.67–1.91) 1.20 (0.81–1.78) 1.97 (1.04–3.74) 1.40 (1.18–1.67) IV–V 1.11 (0.81–1.52) 0.81 (0.44–1.50) 1.23 (0.83–1.83) 1.95 (0.98–3.88) 1.43 (1.19–1.73) VI 1.05 (0.72–1.56) 1.48 (0.75–2.92) 1.31 (0.76–2.27) 2.20 (0.97–4.96) 1.32 (1.04–1.67) Educational level High## 1 1 1 1 Medium 1.21 (0.89–1.65) 0.91 (0.57–1.47) 1.44 (0.95–2.17) 2.15 (1.10–4.23) 1.08 (0.92–1.28) Low 1.32 (0.99–1.77) 1.13 (0.72–1.78) 1.53 (1.04–2.25) 2.83 (1.48–5.41) 1.33 (1.14–1.56) Fully adjusted¶¶ Occupational classƒ I## 1 1 1 1 1 II 1.25 (0.90–1.73) 1.52 (0.91–2.56) 1.16 (0.74–1.82) 1.50 (0.75–3.03) 1.33 (1.09–1.62) III 1.08 (0.80–1.47) 1.23 (0.73–2.08) 1.20 (0.81–1.78) 1.52 (0.77–3.01) 1.38 (1.15–1.66) IV–V 1.05 (0.69–1.60) 0.76 (0.35–1.63) 1.37 (0.79–2.39) 1.37 (0.55–3.42) 1.40 (1.09–1.80) VI 1.01 (0.61–1.70) 1.36 (0.57–3.25) 1.26 (0.66–2.42) 2.23 (0.78–6.34) 1.36 (0.98–1.89) Educational level High## 1 1 1 1 1 Medium 1.18 (0.86–1.63) 0.93 (0.56–1.53) 1.37 (0.90–2.09) 2.13 (1.02–4.45) 1.11 (0.93–1.33) Low 1.40 (1.03–1.89) 1.36 (0.85–2.17) 1.50 (1.00–2.25) 2.49 (1.21–5.13) 1.31 (1.10–1.56) CI : confidence interval; IRR: incidence RR. #: Only subjects with serum immunoglobulin E measurements were included (except bronchitis category). ¶: excludes Tartu (Estonia) and Bordeaux (France) centres; +: includes only people with asthma score 0 at baseline; §: for age, sex and centre; ƒ: I for managers and professionals, II for technicians and associate professionals, III for other nonmanual workers, IV for skilled manual workers, V for semi-skilled/unskilled manual workers and VI for unclassifiable/unknown; ##: reference category; ¶¶: for age, sex, country, body mass index, family history of asthma, number of siblings, exposure to environmental tobacco smoke, smoking status, respiratory infections before 5 yrs of age, mould or mildew in the home in the previous 12 months, rhinitis and high occupational exposure to pollutants.
