Table 2.
Impact of smoking status on COPD development.
| Sex | Smoking status | N | Event | Duration | IR, per 1,000 PY | HR (95% CI) | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Model 1 | Model 2 | Model 3 | ||||||||||||||||||||||
| Total | Non | 3,485,089 | 6,627 | 28963394.53 | 0.2288 | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | Former | 633,122 | 1,536 | 5367167.29 | 0.2862 | 1.247 (1.180–1.318) | 1.208 (1.135–1.285) | 1.206 (1.134–1.283) | Current | 2,189,365 | 5,626 | 18369092.08 | 0.3063 | 1.336 (1.290–1.385) | 1.460 (1.394–1.529) | 1.455 (1.389–1.524) |
| Male* | Non | 1,148,534 | 2,192 | 9605130.78 | 0.2282 | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | Former | 547,055 | 1,320 | 4670421.89 | 0.2826 | 1.235 (1.153–1.322) | 1.116 (1.041–1.197) | 1.115 (1.040–1.195) | Current | 2,039,294 | 5,193 | 17160746.25 | 0.3026 | 1.324 (1.260–1.392) | 1.395 (1.324–1.469) | 1.390 (1.320–1.464) |
| Female* | Non | 2,336,555 | 4,435 | 19358263.75 | 0.2291 | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | Former | 86,067 | 216 | 696745.4 | 0.3100 | 1.358 (1.185–1.557) | 1.389 (1.210–1.595) | 1.388 (1.210–1.594) | Current | 150,071 | 433 | 1208345.83 | 0.3583 | 1.573 (1.425–1.736) | 1.658 (1.497–1.837) | 1.654 (1.493–1.833) |
Model 1, non-adjusted; Model 2, adjusted for age, sex, BMI, alcohol consumption, regular exercise, income, pneumonia, asthma; Model 3, adjusted for age, sex, BMI, alcohol consumption, regular exercise, income, pneumonia, asthma, diabetes mellitus, hypertension, dyslipidemia. *Sex was excluded from multivariate models. COPD, chronic obstructive pulmonary disease; IR, incidence rate; PY, person-year; HR, hazard ratio; CI, confidence interval; Ref., reference.