A decrease in disease activity score (DAS) level is associated with a decrease in health assessment questionnaire...

Area of Science:

• Rheumatology
• Clinical Trial Analysis
• Health Outcomes Research

Background:

• Recent-onset rheumatoid arthritis (RA) requires effective treatment strategies.
• Disease activity steering is a key approach in managing RA.
• Understanding the link between disease control and functional status is crucial.

Purpose of the Study:

• To evaluate the relationship between reduced disease activity score (DAS) and functional ability.
• To analyze this association over 5 years in recent-onset RA patients under DAS-steered treatment.
• To consider the impact of absolute DAS levels and treatment duration.

Main Methods:

• Utilized data from the BeSt study with a target DAS of ≤2.4.
• Employed linear mixed modeling to assess longitudinal DAS and Health Assessment Questionnaire (HAQ) scores over 5 years.
• Included prior DAS, prior HAQ, change in DAS (delta DAS), time, and their interactions as predictors.

Main Results:

• Previous DAS, delta DAS, log-transformed time, and their interactions, along with previous HAQ, predicted HAQ.
• The association between delta DAS and HAQ was independent of follow-up duration.
• A decrease in DAS from a higher baseline resulted in a smaller HAQ improvement compared to a similar decrease from a lower baseline, indicating a non-linear relationship.

Conclusions:

• Reduced DAS is consistently linked to improved functional ability throughout 5 years of RA treatment.
• The extent of functional improvement (HAQ) is influenced by both the magnitude of DAS decrease and the absolute DAS level achieved.
• DAS-steered treatment demonstrates a positive impact on functional outcomes in early RA.