Disability Related to the Upper Extremities in Early Rheumatoid Arthritis-Long-Term Course and Disease Variable Impact: A Cohort Study.

OBJECTIVE

To investigate the course of disability related to the upper extremities (UEs) in early rheumatoid arthritis (RA), and to assess correlations between such disability and clinical variables, including grip force.

METHODS

In an inception cohort of patients with early RA (diagnosed 1995-2005, N = 222, follow-up 10 yrs), disability of the UEs was assessed using a subscore of the Health Assessment Questionnaire-Disability Index (HAQ-DI-UE), and average grip force of the dominant hand was measured. Changes between consecutive follow-up visits in the HAQ-DI-UE subscore, and correlations at each visit with key clinical variables, were assessed. The relation between joint involvement and HAQ-DI-UE was examined using multivariate linear regression analysis.

RESULTS

The HAQ-DI-UE decreased significantly from inclusion to the 6-month follow-up (mean change -0.26, 95% CI -0.18 to -0.34), and increased significantly after 2 years. There were fairly strong correlations for HAQ-DI-UE with grip force (r = -0.50 to -0.62), patient global assessment (r = 0.53 to 0.64), and patient-reported pain (r = 0.54 to 0.60) at all timepoints through 5 years, but only moderate to weak correlations with swollen joints, C-reactive protein, and erythrocyte sedimentation rate. At inclusion, wrist synovitis and tender proximal interphalangeal joints both had an independent effect on HAQ-DI-UE, whereas tenderness of the shoulder and the wrist had a greater importance at 6 months.

CONCLUSION

Disability related to the UEs decreased significantly during the first 6 months, and increased again after 2 years. The correlations with clinical variables underline the major effect of pain and impaired hand function in early RA.