Participant characteristics*
| Variable | Patients with RA (n=223) | Controls (n=31 684) | P value |
| Women, n | 139 (62%) | 17 615 (57%) | 0.044 |
| Age, years | 65 (58, 72) | 54 (42, 64) | <0.001 |
| Body mass index, kg/m2 | 27.4 (24.5, 30.5) | 26.6 (24.1, 29.5) | 0.015 |
| Total cholesterol, mmol/L | 5.6 (4.7, 6.3) | 5.4 (4.7, 6.2) | 0.30 |
| HDL cholesterol, mmol/L | 1.3 (1.1, 1.6) | 1.3 (1.1, 1.6) | 0.11 |
| Creatinine, μmol/L | 84 (74, 94) | 82 (73, 92) | 0.15 |
| Diabetes, n | 18 (8%) | 1335 (4%) | 0.004 |
| Hypertension, n | 138 (62%) | 12 757 (40%) | <0.001 |
| Smoking | <0.001 | ||
| Never smoker | 79 (35%) | 15 638 (49%) | |
| Previous smoker | 97 (44%) | 10 033 (32%) | |
| Present smoker | 47 (21%) | 6013 (19%) | |
| C-reactive protein, mg/L | 2.4 (1.2, 6.5) | 1.2 (0.6, 2.6) | <0.001 |
| C-reactive protein ≥3.0 mg/L, n | 98 (44%) | 6867 (22%) | <0.001 |
| C-reactive protein ≥5.0 mg/L, n | 66 (30%) | 3767 (12%) | <0.001 |
| eCRF, mL×min−1×kg−1 | 26.1 (20.1, 30.8) | 35.1 (35.0, 35.2) | <0.001 |
| Mortality, n | 54 | 3124 | <0.001 |
| Mortality, %† | 24.1 (18.1, 31.6) | 9.9 (9.5, 10.2) | |
| Age at RA diagnosis, years | 55 (46, 63) | NA | |
| Years with RA at HUNT3 | 5 (9, 16) | NA | |
| Seropositive‡ | 157 (70%) | NA |
*Data are given as number (%) or median (25th,75th percentile). Patients with RA and controls were compared using the Χ2 test or Mann-Whitney U test.
†95% CIs in parentheses, calculated using the binomial distribution.
‡Seropositive: positive for IgM rheumatoid factor and/or anti-citrullinated protein antibodies.
eCRF, estimated cardiorespiratory fitness; HDL, high-density lipoprotein; HUNT3, third survey of the Trøndelag Health Study; NA, not applicable; RA, rheumatoid arthritis.