Table 2.
Baseline characteristics of study participants stratified by RA diagnosis during follow-up
| Characteristic | Incident RA (n = 92) | No incident RA (n = 3944) | P-value |
|---|---|---|---|
| Bariatric surgery, n (%) | 47 (51) | 1955 (50) | 0.77 |
| Age, years, mean (s.d.) | 48 (6) | 48 (6) | 0.55 |
| Sex, male, n (%) | 18 (20) | 1161 (29) | 0.04 |
| BMI, kg/m2, mean (s.d.) | 42 (5) | 41 (5) | 0.16 |
| Obesity duration, years, mean (s.d.) | 17 (8) | 16 (8) | 0.68 |
| ESR, mm/h, mean (s.d.) | 18 (11) | 15 (10) | 0.06 |
| CRPa, mg/L, mean (s.d.) | 10.1 (12.5) | 7.4 (7.7) | 0.002 |
| Current or former smoker, n (%) | 66 (72) | 2500 (63) | 0.10 |
| Seropositive, n (%)b | 51 (68) | – |
a
Measurements of CRP were available for 3693 study participants at baseline.
b
Data were obtained by a review of the ICD codes from the National Patient Register. Subjects who were seronegative at the diagnosis of RA but later developed seropositivity according to the ICD codes are classified here as seropositive. Seventeen subjects are not included due to unknown status.