Table 1.
Characteristics of participations by smoking status at baseline (N = 12,489)
| Smoking Status | P valuea | |||||||
|---|---|---|---|---|---|---|---|---|
| Never smokers (n = 7443, 59.6%) | Current smokers (n = 1718, 13.8%) | Ex-smokers (years since smoking cessation; n = 3328, 26.6%) | ||||||
| ≤ 2 years (n = 383) | 3–5 years (n = 411) | 6–10 years (n = 600) | 11–15 years (n = 407) | > 15 years (n = 1527) | ||||
| Age (years) (mean ± SD) | 73.9 ± 6.0 | 72.3 ± 5.5 | 72.6 ± 5.1 | 73.0 ± 5.4 | 73.3 ± 5.4 | 74.2 ± 5.5 | 75.3 ± 6.2 | < 0.0001 |
| Male (%) | 20.2 | 88.2 | 90.3 | 89.5 | 92.2 | 94.4 | 95.6 | < 0.0001 |
| Obesity (%)b | 32.2 | 22.1 | 26.0 | 30.9 | 34.4 | 30.9 | 30.8 | < 0.0001 |
| Education level (junior high school or less) (%)c | 27.4 | 34.3 | 32.2 | 32.0 | 31.2 | 34.3 | 33.8 | < 0.0001 |
| Current drinkers (%) | 22.5 | 64.0 | 55.9 | 54.5 | 58.2 | 55.8 | 60.1 | < 0.0001 |
| Time spent walking (≤ 0.5 h/day) (%) | 35.5 | 33.9 | 39.6 | 36.0 | 34.1 | 36.6 | 32.7 | 0.21 |
| Psychological stress (%)d | 4.6 | 4.3 | 2.4 | 3.7 | 4.1 | 3.9 | 4.1 | 0.54 |
| History of diseases (%) | ||||||||
| Stroke | 2.2 | 3.1 | 4.4 | 3.7 | 4.3 | 5.2 | 4.3 | < 0.0001 |
| Myocardial infarction | 3.5 | 3.8 | 7.3 | 9.3 | 10.3 | 9.1 | 9.0 | < 0.0001 |
| Hypertension | 56.0 | 55.1 | 56.1 | 52.8 | 59.8 | 62.4 | 62.5 | < 0.0001 |
| Diabetes | 10.5 | 12.5 | 13.6 | 15.3 | 16.8 | 16.7 | 15.5 | < 0.0001 |
aP values were calculated by using χ2 test for variables of proportion and one-factor ANOVA for continuous variables
bBody mass index ≥ 25 kg/m2
cAge at completion of education < 16 years old
dKessler 6-item Psychological Distress Scale score ≥ 13