Comparison of demographic and questionnaire data at baseline in patients with rheumatoid arthritis and in community controls according to their response to the HAQ questionnaire (HAQ <1 v HAQ ⩾1)
| Variable | Patients with rheumatoid arthritis | Community controls | All subjects: p value for patients with RA v controls | ||||||
|---|---|---|---|---|---|---|---|---|---|
| HAQ <1 (n = 691) | HAQ ⩾1 (n = 404) | Total (n = 1095) | p Value | HAQ <1 (n = 1343) | HAQ ⩾1 (n = 147) | Total (n = 1490) | p Value | ||
| Results for continuous variables are given as mean (SE), and for dichotomous variables as percentages. Student’s two tailed t test was used for continuous variables, and the χ2 test for non-continuous variables. | |||||||||
| HAQ, health assessment questionnaire; RA, rheumatoid arthritis; RF, rheumatoid factor; VAS, visual analogue scale. | |||||||||
| Age (years) | 62.1 (0.5) | 66.3 (0.6) | 62.4 (0.4) | <0.001 | 53.7 (0.4) | 72.1 (1.2) | 55.5 (0.4) | <0.001 | <0.001 |
| Sex (% of female) | 67.9% | 76.2% | 71.0% | 0.003 | 71.2% | 81.0% | 72.1% | 0.012 | 0.456 |
| Duration of rheumatoid arthritis (years) | 9.2 (0.3) | 15.0 (0.5) | 11.3 (0.3) | <0.001 | |||||
| Positive RF (%) | 64.8% | 75.3% | 68.6% | 0.001 | |||||
| Erosions present (%) | 53.7% | 70.5% | 59.9% | <0.001 | |||||
| HAQ (0–3) | 0.32 (0.01) | 1.71 (0.03) | 0.83 (0.02) | <0.001 | 0.10 (0.01) | 1.84 (0.05) | 0.27 (0.02) | <0.001 | <0.001 |
| Pain VAS (0–100) | 23.1 (0.7) | 50.7 (1.1) | 33.2 (0.7) | <0.001 | 16.3 (0.6) | 57.4 (2.3) | 20.1 (0.7) | <0.001 | <0.001 |
| Global VAS (0–100) | 25.0 (0.7) | 50.1 (1.0) | 34.1 (0.7) | <0.001 | 18.2 (0.5) | 58.0 (1.8) | 22.0 (0.6) | <0.001 | <0.001 |
| Number of comorbidities | 1.5 (0.1) | 2.4 (0.1) | 1.9 (0.1) | <0.001 | 1.4 (0.0) | 3.5 (0.2) | 1.6 (0.0) | <0.001 | <0.001 |
| Education (years) | 10.0 (0.2) | 8.3 (0.2) | 9.4 (0.1) | <0.001 | 11.1 (0.1) | 7.8 (0.4) | 10.9 (0.1) | <0.001 | <0.001 |
| Body mass index (kg/m2) | 26.1±0.2 | 26.3±0.3 | 26.2±0.1 | 0.496 | 26.1 (0.1) | 27.0 (0.5) | 26.2 (0.1) | 0.053 | 0.954 |
| Mortality over 2 years, (%) | 2.3% | 10.1% | 5.2% | <0.001 | 1.0% | 13.6% | 2.2% | <0.001 | <0.001 |