Smoking cessation outcomes in relation to nicotine replacement therapy (NRT)
| Total N=2591 | No NRT N=1296 | NRT N=1295 | Unadjusted OR (95% CI; p value) | Adjusted OR* (95% CI; p value) | Adjusted OR† (95% CI; p value) | |
|---|---|---|---|---|---|---|
| Outcomes at 6 months, n (%) | ||||||
| Prolonged cessation (inc. questionnaire data) (primary outcome) | 490 (18.9) | 261 (20.1) | 229 (17.7) | 0.85 (0.70 to 1.04; p=0.11) | 0.86 (0.70 to 1.06; p=0.16) | 0.84 (0.66 to 1.07; p=0.17) |
| Carbon monoxide validated prolonged cessation | 207 (8.0) | 122 (9.4) | 85 (6.6) | 0.67 (0.50 to 0.90; p=0.008) | 0.65 (0.48 to 0.88; p=0.005) | 0.63 (0.45 to 0.86; p=0.004) |
| Self-reported cessation for ≥7 days | 531 (20.5) | 283 (21.8) | 248 (19.1) | 0.85 (0.70 to 1.03; p=0.09) | 0.85 (0.70 to 1.04; p=0.13) | 0.85 (0.67 to 1.07; p=0.17) |
| Carbon monoxide validated cessation for ≥7 days | 200 (7.7) | 119 (9.2) | 81 (6.2) | 0.66 (0.49 to 0.88; p=0.006) | 0.64 (0.47 to 0.87; p=0.004) | 0.62 (0.45 to 0.86; p=0.004) |
| Reported cessation for ≥3 months | 401 (15.5) | 216 (16.6) | 185 (14.3) | 0.83 (0.67 to 1.03; p=0.09) | 0.84 (0.67 to 1.05; p=0.14) | 0.86 (0.66 to 1.10; p=0.23) |
| Reports one or more quit attempts lasting >24 h† | 594 (22.9) | 289 (22.3) | 305 (23.5) | 1.07 (0.88 to 1.28; p=0.49) | 1.05 (0.86 to 1.27; p=0.60) | 1.15 (0.88 to 1.50; p=0.30) |
| Median (IQR) no. quit attempts reported | 2 (1–3) | 2 (1–4) | 2 (1–3) | n/a | n/a | n/a |
| Outcomes at 1 month, n (%) | ||||||
| Prolonged cessation since quit date | 1040 (40.1) | 520 (40.1) | 520 (40.1) | 0.99 (0.85 to 1.16; p=0.93) | 1.01 (0.86 to 1.19; p=0.88) | 1.00 (0.80 to 1.26; p=0.96) |
| Reported cessation for ≥7 days | 831 (32.0) | 417 (32.2) | 414 (32.0) | 0.98 (0.83 to 1.16; p=0.85) | 0.99 (0.84 to 1.18; p=0.97) | 0.97 (0.77 to 1.22; p=0.80) |
*Adjusted for age, gender, educational level and heaviness of smoking index; 2397 cases included in adjusted analyses.
†Additionally adjusted for all forms of non-trial support.