Clinical Disease Activity Index (CDAI) for Rheumatoid Arthritis

Why Use

The CDAI provides an excellent overview of a patient's disease severity (it correlates closely with the SDAI which requires laboratory data) and the DAS-28 (which is a much longer, 28-joint assessment). The CDAI can also help guide therapy based on severity of disease (see “Next Steps”).

When to Use

All patients with rheumatoid arthritis. Re-assessing patients after starting a new medication for RA.

Formula

Pearls / Pitfalls

Assessment of disease activity in rheumatoid arthritis (RA) should be viewed as a dynamic, on-going process; many experts recommend assessing the Clinical Disease Activity Index (CDAI) at every patient visit. Early treatment is important for optimal RA outcomes, and the CDAI can help give a gestalt view of a patient’s disease severity and activity.

Critical Actions

Patients with high activity scores should receive early and aggressive RA medications with close follow-up, as attaining low activity or remission-level scores may prevent disease progression and disability.

More Information

Score interpretation: CDAI Score Range Disease Severity ≤ 2.8 Remission > 2.8 - 10.0 Low > 10.0 - 22.0 Moderate > 22.0 High