Does expert opinion match the definition of lupus low disease activity state? Prospective analysis of 500 patients from a Spanish multicentre cohort

Objectives To apply the lupus low disease activity state (LLDAS) definition within a large cohort of patients and to assess the agreement between the LLDAS and the physician's subjective evaluation of lupus activity. Methods We conducted a cross-sectional analysis of a prospective multicentre study of SLE patients. We applied the LLDAS and assessed whether there was agreement with the clinical status according to the physician's opinion. Results A total of 508 patients [92% women; mean age 50.4 years (s.d. 3.7)] were recruited and 304 (62.7%) patients were in the LLDAS. According to physician assessment, 430 (86.1%) patients were classified as remission or low activity. Overall agreement between both evaluations was 71.4% (95% CI: 70.1, 70.5) with a Cohen's kappa of 0.3 [interquartile range (IQR) 0.22-0.37]. Most cases (96.1%) in the LLDAS were classified as remission or low activity by the expert. Of the patients who did not fulfil the LLDAS, 126 (70.4%) were classified as having remission/low disease activity. The main reasons for these discrepancies were the presence of new manifestations compared with the previous visit and a SLEDAI 2K score >4, mainly based on serological activity. Conclusions Almost two-thirds of SLE patients were in the LLDAS. There was a fair correlation between the LLDAS and the physician's evaluation. This agreement improves for patients fulfilling the LLDAS criteria. The discordance between both at defining lupus low activity, the demonstrated association of the LLDAS with better outcomes and the fact that the LLDAS is more stringent than the physician's opinion imply that we should use the LLDAS as a treat-to-target goal.