Patient and symptom characteristics (n=102)
| Characteristic | |
|---|---|
| Women, n (%) | 74 (72.5) |
| Age in years, mean (SD) | 43.3 (13.3) |
| Family history of RA, n (%) | 50 (66 (32.4) |
| Symptom duration | |
| In weeks, median (IQR) | 15.1 (8.9–26.4) |
| ≤12 weeks, n (%) | 36 (36.7) |
| Symptom onset | |
| Gradual (>1 week, either continuous or waxing and waning), n (%) | 80 (78.4) |
| Subacute (<1 week), n (%) | 21 (20.8) |
| Character of initial symptoms*† | |
| Pain, n (%) | 95 (93.1) |
| Stiffness, n (%) | 70 (68.6) |
| Functional disability, n (%) | 28 (27.5) |
| Localisation of initial symptoms* | |
| Small joints, n (%) | 81 (79.4) |
| Small and large joints, n (%) | 15 (14.7) |
| Large joints, n (%) | 6 (5.9) |
| Localisation of initial symptoms* | |
| Upper extremities, n (%) | 68 (66.7) |
| Upper and lower extremities, n (%) | 24 (23.5) |
| Lower extremities, n (%) | 9 (8.8) |
| Localisation of initial symptoms* | |
| Symmetrical, n (%) | 73 (71.6) |
| Asymmetrical, n (%) | 29 (28.4) |
| Presence of inflammatory character joint pain‡§, n (%) | 78 (76.5) |
| Presence of morning stiffness ≥60 minutes‡, n (%) | 44 (43.1) |
| Presence of fatigue‡, n (%) | 27 (26.5) |
| HAQ median (IQR) | 0.56 (0.25–0.88) |
| Daily use of NSAIDs, n (%) | 20 (19.6) |
| BMI in kg/m2 median (IQR) | 25.1 (22.8–29.6) |
| 68-TJC median (IQR) | 6 (3–11) |
| Current smoker, n (%) | 21 (20.6) |
| Current alcohol user¶, n (%) | 66 (66.7) |
| Autoantibody status | |
| ACPA- and/or IgM-RF-positive, n (%) | 29 (28.4) |
| Only ACPA-positive (>7 U/mL), n (%) | 4 (3.9) |
| Only IgM-RF-positive (>3.5 IU/mL), n (%) | 14 (13.7) |
| ACPA- and IgM-RF-positive, n (%) | 11 (10.8) |
| Increased CRP (>10 mg/L), n (%) | 14 (13.7) |
| Increased ESR (reference for age), n (%) | 13 (12.7) |
Symptoms were noted by rheumatologists as reported by the patients. Data on symptom duration and BMI were missing in four patients; symptom onset, intermittent symptoms present and initial localisation (upper, upper and lower, lower, symmetrical, asymmetrical) were missing in one patient; 68-TJC was missing in three patients; alcohol use was missing in three patients; and HAQ was missing in 24 patients.
*Initial symptoms refer to the first symptoms.
†A patient can have more than one character of the initial symptoms.
‡The presence of symptoms refers to the presence of these symptoms at the baseline visit.
§Defined as joint pain that is worst in the early morning and improves with movement during the day.
¶Patients not consuming daily alcohol but only one or few beverages a week were considered as alcohol users.
ACPA, anti-citrullinated peptide antibody; BMI, body mass index; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; HAQ, Health Assessment Questionnaire; IgM-RF, immunoglobulin M rheumatoid factor; NSAID, non-steroidal anti-inflammatory drug; RA, rheumatoid arthritis; TJC, tender joint count.