Are prognostic factors adequately selected to guide treatment decisions in patients with rheumatoid arthritis? A collaborative analysis from three observational cohorts.

Objective: To investigate the impact of indicators of unfavorable prognosis ("poor prognostic factors") on the achievement of low disease activity (LDA)/remission in patients with rheumatoid arthritis (RA).

Methods: Biologic DMARD-naïve patients with RA from three observational cohorts were examined. N = 713 patients started their 1st csDMARD, n = 1613 switched to the 2nd csDMARD and n = 388 to the 1st TNF-inhibitor. High disease activity (DAS28 > 5.1), autoantibodies (RF/ACPA positive), prevalent erosions, functional limitation (HAQ ≥ 1.2), comorbidities, obesity (BMI > 30 kg/m), and smoking were evaluated as prognostic factors. Generalized regression analyses were applied to investigate prognostic factors regarding the achievement of LDA (DAS28 < 3.2) or remission (DAS28 < 2.6) within six months.

Results: At baseline, RF/ACPA positivity was most frequent in all cohorts (60.3-75.3%), followed by DAS28 > 5.1 (35-57.7%), HAQ ≥ 1.2 (40.5-52.5%), ≥ 2 comorbidities (31.4-54.1%) and erosions (17.1-46.1%). Remission was achieved by 39% (1st-csDMARD), 26% (2nd-csDMARD) and 30% (1st-TNFi). In adjusted regression models DAS28 > 5.1 (OR: 0.41 [0.30;0.56]), HAQ ≥ 1.2 (0.56 [0.42;0.74]), current smoking (0.72 [0.53;0.97], obesity (0.66 [0.49;0.89] and ≥ 2 comorbidities (0.57 [0.40;0.80]) were independently associated with a lower chance to achieve remission within six months (ORs for 2nd-csDMARD). The proportion of patients in LDA/remission declined by 6-12%-points if DAS28 > 5.1 was present at baseline and by 15-27%-points if functional limitation, comorbidities and obesity were additionally present. In all cohorts RF/ACPA positivity and erosions were not associated with achieving LDA/remission.

Conclusions: While RF/ACPA status and erosions do not affect the achievement of LDA/remission, high disease activity, functional limitation, comorbidities and obesity should be considered as unfavorable prognostic factors in patients starting the 1st or 2nd DMARD strategy.