Table 2.
Risk of bladder cancer in incident metformin users compared with incident sulfonylurea (SU) only users
| Exposure category | Bladder cancer n = 693 | Age/gender adj HR | Adj HR (95% CI) † | Adj HR (95% CI) ‡ | |||||
|---|---|---|---|---|---|---|---|---|---|
| (95% CI) | |||||||||
| SU only use | 124 | Reference | |||||||
| All metformin users (1 + 2) | 461 | 1.15 | (0.92, 1.43) | 1.12 | (0.90, 1.40) | 1.13 | (0.90, 1.40) | ||
| Metformin only users (1) | 247 | 1.08 | (0.86, 1.37) | 1.06 | (0.84, 1.34) | 1.03 | (0.81, 1.31) | ||
| Metformin in combination users (2) | 214 | 1.23 | (0.97, 1.56) | 1.21 | (0.95, 1.54) | 1.27 | (0.99, 1.62) | ||
| Metformin with SUs | 129 | 1.24 | (0.95, 1.60) | 1.22 | (0.94, 1.58) | 1.27 | (0.97, 1.65) | ||
| Metformin with glinides § | <5 events | 1.83 | (0.45, 7.41) | 1.80 | (0.44, 7.32) | 1.87 | (0.46, 7.59) | ||
| Metformin with glitazones ¶ | 23 | 1.15 | (0.73, 1.83) | 1.12 | (0.71, 1.78) | 1.15 | (0.72, 1.83) | ||
| Metformin with DPP‐4 inhibitors * | 7 | 1.37 | (0.63, 2.99) | 1.33 | (0.61, 2.90) | 1.33 | (0.61, 2.91) | ||
| Metformin with insulin | 14 | 1.11 | (0.63, 1.94) | 1.07 | (0.61,1.89) | 1.19 | (0.67, 2.13) | ||
| Metformin with more than one combination | 39 | 1.27 | (0.87, 1.86) | 1.23 | (0.84, 1.81) | 1.33 | (0.90, 1.97) | ||
| Other ADD users | 58 | 1.53 | (1.11, 2.12) | 1.52 | (1.10, 2.10) | 1.57 | (1.13, 2.19) | ||
| Insulin only | 26 | 1.77 | (1.15, 2.72) | 1.75 | (1.14, 2.69) | 1.92 | (1.24, 2.99) | ||
| Glitazones only | <5 events | 1.02 | (0.38, 2.79) | 1.01 | (0.37, 2.76) | 1.03 | (0.38, 2.81) | ||
| DPP‐4‐inhibitors only | <5 events | 2.37 | (0.75, 7.53) | 2.31 | (0.73, 7.34) | 2.29 | (0.72, 7.29) | ||
| Glinides only | <5 events | 2.05 | (0.29, 14.71) | 2.09 | (0.29,14.98) | 2.14 | (0.30, 15.31) | ||
| SUs combined (not with metformin) | 21 | 1.29 | (0.81, 2.07) | 1.28 | (0.80, 2.06) | 1.37 | (0.85, 2.20) | ||
| Others | <5 events | 2.44 | (0.77, 7.71) | 2.40 | (0.76, 7.59) | 2.58 | (0.81, 8.20) | ||
| Past SU user (not metformin with SU) | 16 | 0.66 | (0.39, 1.11) | 0.67 | (0.39, 1.12) | 0.68 | (0.40, 1.14) | ||
| Past metformin user (e.g. only insulin) | 23 | 0.54 | (0.34, 0.86) | 0.52 | (0.33,0.83) | 0.52 | (0.33, 0.83) | ||
| Past other | 11 | 0.37 | (0.20, 0.69) | 0.36 | (0.19, 0.67) | 0.37 | (0.20, 0.70) | ||
CI, confidence interval; HR, hazard ratio; Incident, all index patients are included after 1 year lead‐in time without anti‐diabetic drugs (ADD) prescription; SU, glibenclamide, gliclazide, glimepiride, glipizide, gliquidon.
†
Adjusted for age, gender, smoking and BMI.
‡
Adjusted for † and duration of diabetes.
§
Repaglinide.
¶
Pioglitazone, rosiglitazone.
*
Saxagliptin, sitagliptin, vildagliptin.