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.