Table 2.
Study characteristics of smokers and quitters
| Study | Country | No of participants | Exposure/control | Age/sex | Included or excluded from meta-analysis Study design |
||
|---|---|---|---|---|---|---|---|
| Smoker | Quitter | Smoker | Quitter | ||||
| Lycett et al. [51] T2DM | UK | 10,692 | 7561 | 3131 | 61.6 (12.1) 58.4% M |
61.6 (11.3) 64.4% M |
Included Retrospective cohort study |
| Iino et al. [52] T2DM | Japan | 31 | 16 | 15 | 60.1 (2.5) 81.25% M |
62.7 (2.5) 80% M |
Excluded (subjects started smoking within 12 months) Prospective cohort study |
| Reynolds et al. [42] T2DM | USA | 125 | 66 | 59 | 18.6 (2.5) 39.4% |
17.9 (2.4) 47.5% M |
Included Cross sectional study |
| Reynolds et al. [42] T1DM | USA | 412 | 203 | 209 | 18.3 (2.2) 50.7% M |
17.7 (2.7) 47.4% M |
Included Cross sectional study |
| Ohkuma et al. [50] T2DM | Japan | 2490 | 679 | 1306 | 61.2 (10) | 66.9 (9.2) | Included Cross sectional study |