Table 6.
Determinants at baseline (1993–1997) of incident COPD at follow-up (2013) among 54,829 participants in the DCH cohort
| Model 1, HR (95% CI) | Model 2, HR (95% CI) | Model 3, HR (95% CI) | |
|---|---|---|---|
| Age 50–54 years | 1.00 | 1.00 | – |
| Age 55–59 years | 1.10 (1.00–1.22) | 0.87 (0.78–0.97) | – |
| Age 60–65 years | 1.30 (1.16–1.46) | 0.74 (0.66–0.84) | – |
| Female | 1.00 | 1.00 | 1.00 |
| Male | 1.01 (0.94–1.09) | 0.73 (0.65–0.84) | 0.73 (0.66–0.80) |
| Never smoked | 1.00 | 1.00 | 1.00 |
| Previously smoked | 3.34 (2.81–3.98) | 1.09 (0.86–1.37) | 1.22 (0.98–1.52) |
| Currently smoke | 14.54 (12.46–16.96) | 1.57 (1.20–2.06) | 1.86 (1.44–2.40) |
| Smoking duration (per 10 years) | 1.96 (1.90–2.02) | 1.59 (1.50–1.69) | 1.52 (1.44–1.60) |
| Smoking intensity (per 10 g/day) | 1.50 (1.48–1.52) | 1.18 (1.14–1.22) | 1.19 (1.44–1.60) |
| No ETS | 1.00 | 1.00 | 1.00 |
| Exposed to ETS | 4.50 (4.01–5.05) | 1.21 (1.06–1.38) | 1.21 (1.15–1.23) |
| No occupational exposure | 1.00 | 1.00 | 1.00 |
| Had occupational exposures | 1.78 (1.65–1.92) | 1.27 (1.17–1.39) | 1.29 (1.18–1.41) |
| Underweight (<18.5 kg/m2) | 3.02 (2.34–3.89) | 1.87 (1.45–2.41) | 1.84 (1.43–2.37) |
| Normal (18.5–25 kg/m2) | 1.00 | 1.00 | 1.00 |
| Overweight (25–30 kg/m2) | 0.79 (0.73–0.86) | 0.85 (0.78–0.92) | 0.85 (0.78–0.92) |
| Obese (≥30 kg/m2) | 1.00 (0.90–1.11) | 1.04 (0.93–1.16) | 1.04 (0.93–1.16) |
| Inactive in leisure time | 1.00 | 1.00 | 1.00 |
| Physically active in leisure time | 0.56 (0.52–0.60) | 0.85 (0.78–0.92) | 0.85 (0.79–0.92) |
| Fruit intake (100 g/day) | 0.83 (0.81–0.86) | 0.97 (0.95–1.00) | 0.97 (0.94–1.00) |
| Never used HRT | 1.00 | 1.00 | 1.00 |
| Ever used HRT | 1.25 (1.15–1.36) | 1.24 (1.13–1.37) | 1.24 (1.13–1.38) |
| <8 years of education | 1.00 | 1.00 | 1.00 |
| 8–10 years of education | 0.62 (0.58–0.68) | 0.85 (0.78–0.92) | 0.85 (0.78–0.92) |
| ≥10 years of education | 0.44 (0.40–0.50) | 0.77 (0.68–0.87) | 0.77 (0.68–0.87) |
| Employed | 1.00 | 1.00 | 1.00 |
| Unemployed | 1.73 (1.60–1.87) | 1.27 (1.17–1.38) | 1.22 (1.12–1.32) |
| Single | 1.11 (0.94–1.30) | 1.00 (0.85–1.18) | 1.01 (0.86–1.18) |
| Married | 1.00 | 1.00 | 1.00 |
| Divorced | 1.70 (1.56–1.86) | 1.27 (1.16–1.39) | 1.28 (1.17–1.40) |
| Widowed | 1.32 (1.15–1.53) | 1.05 (0.91–1.21) | 1.02 (0.88–1.18) |
| Comorbid conditions | |||
| No MI | 1.00 | 1.00 | 1.00 |
| Had MI | 2.16 (1.79–2.61) | 1.46 (1.20–1.79) | 1.49 (1.23–1.80) |
| No stroke | 1.00 | 1.00 | 1.00 |
| Had stroke | 2.32 (1.87–2.89) | 1.54 (1.23–1.92) | 1.54 (1.23–1.92) |
| No Diabetes | 1.00 | 1.00 | – |
| Diabetes | 1.17 (0.91–1.49) | 0.98 (0.77–1.26) | – |
| No hypertension | 1.00 | 1.00 | 1.00 |
| Hypertension | 1.10 (1.00–1.21) | 1.17 (1.06–1.29) | 1.17 (1.06–1.29) |
| No hypercholesterolemia | 1.00 | 1.00 | – |
| Hypercholesterolemia | 1.26 (1.11–1.43) | 1.07 (0.93–1.22) | – |
Notes: Model 1, univariate model; Model 2, fully adjusted model, with all variables in the model; Model 3, final model with determinants of asthma by stepwise selection (P<0.05). “–” indicates the variable not being included in model 3.
Abbreviations: COPD, chronic obstructive pulmonary disease; DCH, Danish Diet, Cancer, and Health; HR, hazard ratio; CI, confidence interval; ETS, environmental tobacco smoke; MI, myocardial infarction; HRT, hormone replacement therapy.