Differences in clinical status measures in different ethnic/racial groups with early rheumatoid arthritis: implications for interpretation of clinical trial data.

OBJECTIVE: Studies have documented differences in health status, disease prevalence, treatment outcomes, and healthcare utilization among different ethnic groups. We compared patients with early rheumatoid arthritis (RA) of different ethnic/racial groups according to disease activity measures, to identify possible differences in patterns of severity of clinical status.
METHODS: An early RA treatment evaluation registry (ERATER) with more than 500 patients with less than 3 years of RA was established; 118 ERATER patients are followed in Brooklyn, NY, USA. At each visit, all patients complete a multidimensional Health Assessment Questionnaire (MDHAQ), including functional status, pain, fatigue, global assessment on a 10 cm visual analog scale, psychological distress, and duration of morning stiffness. Clinical evaluation includes tender and swollen joint counts and erythrocyte sedimentation rate (ESR). Baseline measures were collected before patients started any treatments. Clinical status measures in 3 ethnic/racial groups were compared.
RESULTS: Hispanic patients with RA scored worst in all self-report measures compared to Caucasians and African Americans, with statistically significant differences in MHAQ functional score, psychological distress, and morning stiffness. The groups were not statistically significantly different in joint counts, ESR, or physician global assessment.
CONCLUSION: Our findings indicate differences between ethnic/racial groups in patient derived measures in patients with early RA at presentation. Cultural differences and possible ethnic influences on disease activity measures in clinical trials and clinical care may be important in interpreting differences in prognosis and outcomes of patients with RA.