Table 2.
Hazard ratios for association between pioglitazone and risk of bladder cancer
| Exposure* | No of events | Person years | Incidence rate (95% CI)† | Age and sex adjusted hazard ratio (95% CI) | Fully adjusted hazard ratio (95% CI)‡ |
|---|---|---|---|---|---|
| Primary analysis: | |||||
| No thiazolidinedione¶ | 497 | 558 924 | 88.9 (81.3 to 97.1) | 1.00 (Reference) | 1.00 (Reference) |
| Pioglitazone | 54 | 44 618 | 121.0 (90.9 to 157.9) | 1.68 (1.26 to 2.24) | 1.63 (1.22 to 2.19) |
| Cumulative duration: | |||||
| ≤1 year | 11 | 12 031 | 91.4 (45.6 to 163.6) | 1.35 (0.74 to 2.46) | 1.33 (0.73 to 2.40) |
| 1-2 years | 14 | 11 583 | 120.9 (66.1 to 202.8) | 1.70 (1.00 to 2.91) | 1.66 (0.97 to 2.84) |
| >2 years | 29 | 21 004 | 138.1 (92.5 to 198.3) | 1.84 (1.25 to 2.71) | 1.78 (1.21 to 2.64) |
| P trend | <0.01 | <0.01 | |||
| Cumulative dose: | |||||
| ≤10 500 mg | 18 | 15 646 | 115.0 (68.2 to 181.8) | 1.66 (1.04 to 2.67) | 1.63 (1.02 to 2.60) |
| 10 500-28 000 mg | 18 | 15 356 | 117.2 (69.5 to 185.3) | 1.62 (1.01 to 2.61) | 1.58 (0.98 to 2.55) |
| >28 000 mg | 18 | 13 616 | 132.2 (78.3 to 208.9) | 1.76 (1.08 to 2.87) | 1.70 (1.04 to 2.78) |
| P trend | <0.01 | <0.01 |
*Users of rosiglitazone and users of combination of pioglitazone and rosiglitazone are not displayed in the table, but were considered in the regression model for proper estimation of treatment effects.
†Per 100 000 person years.
‡Adjusted for age, year of cohort entry, sex, alcohol related disorders, smoking status, obesity, haemoglobin A1c, previous cancer, bladder conditions, Charlson comorbidity score, duration of treated diabetes, and urine protein testing.
¶No use of pioglitazone or rosiglitazone.