Background Patient global estimate of clinical status (PATGL) is one of 3 patient self-report measures in the rheumatoid arthritis (RA) core data set, and often is the most sensitive measure to distinguish responses to active treatment from placebo in RA clinical trials. PATGL has also been found an informative measure in patients with rheumatic diseases other than RA. Pain has been found most explanatory of PATGL in RA, but the relative contribution of functional disability, pain and fatigue to explain PATGL in other rheumatic diseases remains poorly characterized.
Objectives To analyze the significance of 3 self-report scores for functional disability, pain and fatigue to explain variation in PATGL in patients with all rheumatic diseases seen in a usual care rheumatology setting, and in subsets with RA, OA, SLE, gout, and all other diagnoses.
Methods All patients seen at a rheumatology clinical setting complete a multidimensional heath assessment questionnaire (MDHAQ) at all visits, which includes physical function in 10 activities; visual analog scales (VAS) for pain, PATGL and fatigue; and demographic variables including age, formal education level and gender. The data are recorded in a longitudinal Access database, which was then transferred to STATA Version 11 for analyses. The last available visit of each patient with complete data for all variables was studied in a series of multivariate regressions to analyze the capacity of self-report scores for functional disability, pain and fatigue as independent variables to explain PATGL as the dependent variable in all patients and subgroups with RA, OA, SLE, gout, and other diagnoses.
Results Overall, 2565 patients had complete data, including 517 with RA, 319 OA, 281 SLE, 98 gout and 1350 other diagnoses. Each of the 3 variables - functional disability, pain, and fatigue - independently explained patient global estimate, with highest significance for pain, intermediate for fatigue, and lowest (but significant) for functional disability. Pain was more dominant in RA, while fatigue was of greater relative significance in OA, SLE, gout and other diagnoses (Table). The R2 in these 4 models ranged from 0.57–0.76, indicating robust explanation of variation in PATGL.
Conclusions Pain, fatigue, and functional disability each were independently significant, in that order, to explain variation in PATGL; fatigue scores were less prominent in RA compared to OA, SLE, and gout.
Disclosure of Interest None Declared