Functional Capacity in Patients with Rheumatoid Arthritis and its correlation with Disease Activity

Abstract

Objective: To identify the functional capacity in RA patients on the basis of the HAQ and to determine its correlation with the disease activity on the basis of DAS-28 ESR in a tertiary care hospital in Pakistan.

Methodology: This cross-sectional study was conducted in the Rheumatology Department of Pakistan Institute of Medical Sciences (PIMS), Islamabad, from Nov,  2024 to April, 2025. A sample of 196 patients with Rheumatoid Arthritis (RA) who were all adults and fulfilled the 2010 ACR/EULAR classification criteria. The Health Assessment Questionnaire (HAQ) was used to measure functional status, and Disease Activity Score in 28 joints (DAS28) with erythrocyte sedimentation rate (ESR) was used to measure disease activity. We analyzed the correlation between the DAS28 and HAQ scores based on the descriptive statistics, Pearson and Spearman correlation, linear regression, and multinomial logistic regression. The adjusted regression models were based on age, disease duration and socio-demographic factors.
Results: The average age of the participants was 43 (SD±12.4) years and the average disease duration of the participants was 8.7 (SD ±7.2) years. Mean DAS28 score was 4.56 (SD ±1.06) and Health Assessment Questionnaire (HAQ) was 0.86 (SD ±0.56). Approximately eighty-eight percent of the patients had moderate to high disease activity, and seventy-one percent had moderate disability. There was a strong positive correlation between DAS28 and HAQ scores (r 0.630, p 0.001).
Conclusion: There is a strong correlation between functional disability and disease activity in rheumatoid arthritis patients, with higher scores on DAS28 correlating with greater impairment.