Table 4.
Number of invasive or in situ squamous cell cancers and hazard ratios in 12 558 TNF inhibitor treated (1998-2012) versus 46 409 biologics-naive RA patients, and number of basal cell cancer and hazard ratio in 8827 TNF inhibitor treated (2004-12) RA versus 43 675 biologics-naive RA patients
| Characteristics | Squamous cell cancer | Basal cell cancer | |||
|---|---|---|---|---|---|
| TNF inhibitor treated: No of events (individuals in strata) | Hazard ratio* (95% CI) | TNF inhibitor treated: No of events (individuals in strata) | Hazard ratio (95% CI) | ||
| Overall | 191 (12 558) | 1.43 (1.22 to 1.69) | 236 (8827) | 1.14 (0.98 to 1.33) | |
| Female | 140 (9473) | 1.52 (1.25 to 1.84) | 172 (6601) | 1.06 (0.89 to 1.27) | |
| Male | 51 (3085) | 1.26 (0.92 to 1.70) | 64 (2226) | 1.38 (1.03 to 1.86) | |
| Age at start of TNF inhibitor†: | |||||
| 16-49 years | 12 (3944) | 2.74 (1.10 to 6.82) | 20 (2787) | 1.34 (0.78 to 2.29) | |
| 50-74 years | 142 (7963) | 1.42 (1.17 to 1.73) | 174 (5566) | 1.15 (0.96 to 1.36) | |
| ≥75 years | 37 (650) | 1.36 (0.97 to 1.91) | 42 (474) | 1.40 (1.03 to 1.99) | |
| Time since start of TNF inhibitor‡: | |||||
| ≤6 months | 16 (522) | 1.93 (1.01 to 3.53) | 26 (496) | 0.97 (0.61 to 1.58) | |
| 6.1 months-5 years | 100 (5258) | 1.51 (1.21 to 1.88) | 140 (4937) | 1.24 (1.04 to 1.48) | |
| >5 years | 75 (6778) | 1.27 (0.97 to 1.65) | 70 (3394) | 1.12 (0.78 to 1.60) | |
| Start year of TNF inhibitor: | |||||
| 1998-2003 | 89 (3576) | 1.27 (1.01 to 1.61) | – | – | |
| 2004-12 | 102 (8893) | 1.60 (1.30 to 1.98) | 236 (8827) | 1.13 (0.97 to 1.32) | |
RA=rheumatoid arthritis; TNF=tumour necrosis factor.
*TNF inhibitor treated versus biologic-naive; adjusted for age and sex.
†Test for heterogeneity across strata, P=0.79.
‡Test for heterogeneity across strata, P=0.34.