Table 4.
Hazard ratio (HR), 95% confidence intervals (CI), and details of the statistical analysis for the association between at/around diagnosis smoking status (cessation/continuation) and bladder cancer recurrence-free and progression-free survival.
| Author, Year | Patients Group (According to Smoking Status) | HR | 95% CI | Variables Used for Statistical Adjustment | Exclusion of Events within Predetermined Time from the Start of Follow-Up |
|---|---|---|---|---|---|
| Progression-free survival | |||||
| Grotenhuis, 2015 [27] | Continued smokers | 1.00 (ref.) | Age, cumulative smoking, tumour stage and grade, treatment, other | No or not mentioned | |
| Quitters | 1.24 | 0.55–2.80 | |||
| Sfakianos, 2010 [30] | Never smokers | 1.00 (ref.) | Age, sex, tumour stage | No or not mentioned | |
| Continued smokers | 1.16 | 0.65–2.08 | |||
| Quitters | 0.81 | 0.35–1.88 | |||
| Chen, 2007 [31] (a) | Continued smokers | 1.00 (ref.) | None (unadjusted HR extracted from Kaplan-Meier curve) | Yes (progression within 8 weeks of diagnosis) | |
| Quitters | 0.40 | 0.14–1.16 | |||
| Recurrence-free survival | |||||
| Serretta, 2021 [24] (a) | Continued smokers | 1.00 (ref.) | Age, cumulative smoking, tumour stage and grade, other | No or not mentioned | |
| Quitters | 1.30 | 0.85–1.96 | |||
| van Osch, 2018 [25] (b) | Never smokers | 1.00 (ref.) | Age, sex, tumour stage and grade, other | No or not mentioned | |
| Continued smokers | 1.04 | 0.65–1.66 | |||
| Quitters | 1.47 | 0.63–3.41 | |||
| Grotenhuis, 2015 [27] | Continued smokers | 1.00 (ref.) | Age, cumulative smoking, tumour stage and grade, treatment, other | No or not mentioned | |
| Quitters | 1.36 | 0.87–2.11 | |||
| Lee, 2012 [29] | Never smokers | 1.00 (ref.) | Age, tumour stage and grade, other | No or not mentioned | |
| Continued smokers | 0.85 | 0.59–1.21 | |||
| Quitters | 0.96 | 0.64–1.44 | |||
| Sfakianos, 2010 [30] | Never smokers | 1.00 (ref.) | Age, sex, tumour stage | No or not mentioned | |
| Continued smokers | 1.04 | 0.77–1.40 | |||
| Quitters | 0.75 | 0.49–1.16 | |||
| Chen, 2007 [31] (a) | Continued smokers | 1.00 (ref.) | Cumulative smoking, tumour stage, treatment, other | Yes (any recurrence within 8 weeks of diagnosis) | |
| Quitters | 0.45 | 0.25–0.83 | |||
| Fleshner, 1999 [32] | Former smokers | 1.00 (ref.) | Age, sex, tumour stage and grade, treatment, other | Yes (any recurrence within 3 months of surgery) | |
| Continued smokers | 1.40 | 1.03–1.91 | |||
| Quitters | 0.99 | 0.77–1.25 | |||
(a) The HR and corresponding 95% CI were inverted to make continued smokers the reference category. (b) The HR and 95% CI shown in the table are for the time-to-first recurrence. The HR and 95% CI for the risk of multiple recurrence events is 1.10 (0.72–1.69) for continued smokers and 0.85 (0.35–2.04) for quitters (compared to never smokers, taken as reference). HR: hazard ratio. CI: confidence intervals.