Is pre-assessment for anti-TNF therapy in RA necessary in the UK? Analysis of DAS28 in six centres

National Institute for Health and Clinical Excellence (NICE) guidelines for anti-tumour necrosis factor (TNF) in rheumatoid arthritis (RA) state that two pre-assessments of Disease Activity Score (DAS28) should be performed a month apart. We performed a retrospective audit of data from six centres to determine the stability of DAS28 between assessments, and the proportion of patients still satisfying eligibility criteria at baseline.

All RA patients assessed for anti-TNF from six centres had their pre-assessment DAS28 (DAS-1) compared with their baseline DAS28 (DAS0) using paired t-tests, and a similar analysis for the components of the DAS28. Patients who were no longer eligible for anti-TNF at DAS0 were noted.

Six hundred and seventy-nine RA patients showed no significant change in the DAS28, with a mean DAS-1 of 6.74 and DAS0 of 6.73. (P = 0.86). Of the patients, 97.2% fulfilled the UK eligibility criteria at DAS0. Comparison of the individual components of the DAS28 between the two pre-assessment dates showed that there was no significant difference between either the numbers of swollen joints or the erythrocyte sedimentation rate (ESR), but there was a significant increase in the numbers of tender joints of 1.41 (P < 0.001) and in the visual analogue scale (VAS) of 4.22 (P < 0.001).

The overwhelming majority of patients who fulfil eligibility criteria for anti-TNF drugs 1 month prior to baseline also fulfil the criteria at baseline. There is no significant change in the DAS28 over the month waiting to go onto anti-TNF therapy. A single assessment of the DAS28 would suffice to enable patients to go on to anti-TNF treatment.