To analyze correlations of functional disability scores with other measures of clinical status, in particular, Larsen radiographic scores and pain scores, in patients with rheumatoid arthritis (RA).
The functional capacity of 141 patients with RA (102 women, 39 men; median age 57 years; median disease duration 11.8 years; 83% rheumatoid factor positive) was assessed according to the Stanford Health Assessment Questionnaire (HAQ). Other variables studied included Larsen scores for radiographic damage of the small joints of the hands, wrists, and feet, pain scores by visual analog scale (VAS), Disease Activity Scores, general health scores by VAS, and Beck Depression Inventory (BDI) scores.
The Spearman correlation coefficient comparing HAQ and Larsen scores was 0.277 (P = 0.001) and between HAQ and pain scores 0.652 (P < 0.001). In regression analysis, pain scores explained 41.4% of the variation in HAQ scores, normalized Larsen scores explained 7.3%, and BDI scores explained 5.5%; other variables were not significant in the model.
Functional capacity scores of patients with RA are correlated at higher levels with pain scores than with radiographic scores of small joints.