Severity indices in rheumatoid arthritis: A systematic review

Area of Science:

• Rheumatology
• Clinical Epidemiology
• Health Outcomes Research

Background:

• Rheumatoid arthritis (RA) poses a significant challenge in early disease management.
• Accurate assessment of RA severity is crucial for predicting prognosis and guiding treatment.
• Existing tools may not adequately capture disease severity in the initial stages of RA.

Purpose of the Study:

• To systematically review and evaluate existing tools for assessing rheumatoid arthritis (RA) disease severity.
• To identify instruments suitable for investigating prognostic markers in early RA.
• To determine the suitability of current RA severity indices for contemporary therapeutic strategies.

Main Methods:

• Systematic review of studies developing or validating RA disease severity indices.
• Methodological quality assessment using the COSMIN checklist.
• Evaluation of variable clarity, feasibility, and presence in early RA (first 2 years).
• Grouping of variables by domain to assess redundancy.

Main Results:

• A review of 3,519 articles identified 3 relevant studies.
• The PAS (Patient-Assessed Severity) index showed limited ability of treatment variables to distinguish severity.
• The CIRAS (Claims-Based Index for RA Severity) and RARBIS (RA medical records-based index of severity) indices demonstrated low correlations with established measures like DAS28 and MD-HAQ.
• RARBIS showed weak correlations with treatment intensity and DAS28.

Conclusions:

• No current index effectively assesses RA severity within the first two years of disease, aligning with current treatment paradigms.
• Existing indices lack the necessary adaptation for contemporary RA management strategies.
• Development of a new, dedicated severity index for early RA is warranted.