Effect of anti-TNF drugs on HAQ-DI and cost percentage achieving HAQ-DI MCID over 3 years in patients with RA, PsA, and AS.
| Feature | All Patients, mean (SE) | RA, mean (SE) | PsA, mean (SE) | AS, mean (SE) | p |
|---|---|---|---|---|---|
| Baseline | |||||
| n | 297 | 206 | 57 | 34 | |
| HAQ-DI | 1.37 (0.04) | 1.47 (0.05) | 1.18 (0.08) | 1.06 (0.10) | 0.0002 |
| Year 1 | |||||
| n | 249 | 170 | 52 | 27 | |
| Δ HAQ-DI | −0.27 (0.04) | −0.29 (0.05) | −0.26 (0.08) | −0.19 (0.08) | 0.8192 |
| % HAQ-DI ≥ 0.2 | 51.0 (3.53) | 51.5 (4.37) | 53.2 (7.36) | 43.5 (10.6) | |
| NNT* | 1.96 | 1.94 | 1.88 | 2.30 | |
| Cost, $* | 41,636 | 41,211 | 39,937 | 48,859 | |
| Year 2 | |||||
| n | 156 | 109 | 36 | 11 | |
| Δ HAQ-DI | −0.25 (0.06) | −0.25 (0.07) | −0.26 (0.12) | −0.27 (0.25) | 0.2842 |
| % HAQ-DI ≥ 0.2 | 51.5 (4.69) | 42.7 (5.75) | 42.9 (9.52) | 60.0 (16.3) | |
| NNT* | 1.94 | 2.34 | 2.33 | 1.67 | |
| Cost, $* | 42,077 | 50,752 | 50,535 | 36,220 | |
| Year 3 | |||||
| n | 96 | 69 | 21 | ||
| Δ HAQ-DI | −0.25 (0.07) | −0.23 (0.07) | −0.38 (0.14) | 0.1463 | |
| % HAQ-DI ≥ 0.2 | 51.3 (5.62) | 50.9 (6.80) | 55.0 (11.4) | ||
| NNT* | 1.95 | 1.96 | 1.81 | ||
| Cost, $* | 42,147 | 42,363 | 39,121 | ||
↵* For percentage of HAQ-DI ≥ 0.2. TNF: tumor necrosis factor; HAQ-DI: Health Assessment Questionnaire Disability Index; MCID: minimal clinically important difference; RA: rheumatoid arthritis; PsA: psoriatic arthritis; AS: ankylosing spondylitis; SE: standard error: NNT: number needed to treat.