Table 4.

The crude and adjusted HRs with 95% confidence intervals of drug discontinuation for adalimumab compared with etanercept, stratified by concomitant MTX dose

Follow-up time	All patients	Concomitant MTX 0–10 mg/wk	Concomitant MTX >10 mg/wk	P for modification
All treatment periods	n=4,592	n=2,861	n=1,731
Crude HR	1.12 (1.03–1.22)	1.03 (0.93–1.14)	1.32 (1.15–1.52)	0.009
Adjusted HR	1.06 (0.98–1.16)	0.97 (0.87–1.09)	1.27 (1.10–1.47)	0.013
Within 1 year	n=4,592	n=2,536	n=2,056
Crude HR	1.16 (1.04–1.30)	1.01 (0.88–1.17)	1.48 (1.23–1.78)	0.002
Adjusted HR	1.13 (1.01–1.27)	0.98 (0.85–1.13)	1.48 (1.22–1.78)	0.002
After 1 year	n=2,451	n=1,845	n=606
Crude HR	1.07 (0.94–1.22)	0.98 (0.85–1.13)	1.50 (1.14–1.98)	0.017
Adjusted HR	0.99 (0.87–1.13)	0.91 (0.79–1.06)	1.42 (1.06–1.90)	0.036

Notes: Cox proportional hazard regression analyses were conducted to calculate crude HRs, and adjusted HRs after adjusting for sex, age at anti-TNF initiation, RA duration, Charlson comorbidity index (<2, ≥2) within 1 year before anti-TNF use, use of leflunomide, salazopyrin, nonsteroid anti-inflammatory drugs, MTX (0–10 mg/wk, >10 mg/wk) and corticosteroid (prednisolone equivalent ≤5 mg/d, >5 mg/d) before and after starting anti-TNF use during all treatment periods.

Abbreviations: HRs, hazard ratios; MTX, methotrexate; TNF, tumor necrosis factor; RA, rheumatoid arthritis.