Table 1. Main demographic and clinical characteristics of the RA study cohort.

Number of patients	97
Women/men	68 (70%) / 29 (30%)
Age, years	53 ±14
BMI, kg/m2	25.9 ± 4.9
Disease duration (median), years	1.6 ± 1.5
Positive RF	59 (61%)
Positive ACPA	60 (62%)
Systemic extraarticular manifestations*	16 (16%)
DAS28-ESR at T0Baseline disease activity at T0	3.4 ± 1.8
•    Remission or low activity disease	71 (76%)
•    Moderate	21 (23%)
•    High	1 (1%)
HAQ (0–3)	1.38 ± 0.88
ESR (mm/h) at T0	16.7 ± 13.4
CRP (mg/L) at T0	9.6 ± 16.2
OPG (pmol/L) at T0	3.9 ± 1.8
DKK-1 (pmol/L) at T0	29.9 ± 10.9
Follow-up time between T0 and T1, (median) years	3.3 ± 1.5 (range: 1–7.5)
Treatment during follow-up period    •    Synthetic DMARD monotherapy	62 (64%)
•    Synthetic DMARD combinations	15 (15%)
•    Biological therapy + synthetic DMARD	20 (21%)
•    Concomitant therapy         ○    Low-dose oral glucocorticoid treatment	69 (72%)
○    Accumulated dose of prednisone (g)	4.28 ± 2.86
Osteoporosis treatment
•    None	26 (28%)
•    Calcium and Vitamin D	70 (72%)
•    Antiresorptive or bone forming therapy	36 (37%)
Mean DAS28-ESR between T0 and T1	2.6 ± 0.95
Mean CRP between T0 and T1	2.48 ± 0.87
Radiological progression (annual difference)    •    Erosions	0.19 ± 0.62
•    Joint space narrowing	0.68 ± 1.70
•    Total Sharp–van der Heijde score	0.88 ± 2.20

Results are presented as mean ± standard deviation (median for disease duration and follow-up time) or number of cases with percentages.

*Including rheumatoid nodules, pulmonary manifestations, vasculitis, ocular manifestations, and secondary Sjögren’s syndrome.

Abbreviations: ACPA = anti-citrullinated peptide antibodies; BMI = body mass index; CRP = C-reactive protein; DAS = disease activity score; DKK-1 = Dickkopf-related protein 1; DMARD = disease modifying anti-rheumatic drug; ESR = erythrocyte sedimentation rate; HAQ = Health Assessment Questionnaire; OPG = osteoprotegerin.