Influence of the structure of mood in the assessment of rheumatoid arthritis through the visual analog scale for pain, HAQ and DAS28.

Objective: To analyze the effect of the structure of mood over the following assessment tools for rheumatoid arthritis: visual analog scale (VAS) for pain, HAQ and DAS28.

Patients And Methods: We studied 86 patients with recent onset rheumatoid arthritis, of which 75.7% were female, with a mean age at disease onset of 55 years. All patients were administered the Spanish version of the PANAS questionnaire that evaluates the components of positive (PA) and negative mood (AN). Patients belonged to the registry of new-onset arthritis in our center so clinical information was available for 282 patients visits. To determine the effect of PA and AN on each of the dependent variables we performed three multivariate linear regression models using generalized linear models through the Stata glm command 10.1.

Results: The mean score for PA and AN in our patients was similar to that described for the healthy Spanish population. The high scores on the subscale of AN were associated with worse scores in both the VAS for pain and the HAQ. By contrast, high scores on PA were associated with better outcomes of disease activity measured by DAS28.

Conclusion: The structure of mood may influence the tools we use for evaluating patients with rheumatoid arthritis, so it might be advisable to include the PANAS questionnaire as part of that assessment.