Patients with moderate rheumatoid arthritis as likely to need joint surgery as those with high disease

In some countries, additional treatment with a biological DMARD is based on a disease activity cut-off that excludes RA patients with moderate disease activity. These findings suggest it is not just the RA patients with high disease activity, but also those with moderate RA, who need more intensive treatment, to reduce their risk of needing joint surgery.

"It is well-established that sustained high disease activity in RA results in worse outcomes," said lead author Dr. Elena Nikiphorou of the Rheumatology Department, St Albans City Hospital, UK. "In reality, however, many treated RA patients remain in low or moderate disease activity states and their outcomes, especially in the long term, are less well studied," she added.

"Our data provide an argument for updating existing disease activity cut-off points to allow RA patients with moderate disease activity to receive a biological agent in addition to conventional DMARDs," Dr. Nikiphorou concluded.

In this study, orthopaedic surgery was used as a surrogate marker of joint destruction and failure in RA patients who remained at different disease activity levels over the first five years from the onset of their disease. Joint interventions were categorised into major (mainly large joint replacements), intermediate (e.g. synovectomies, joint fusions and excision arthroplasties of the wrist/hand, foot), or minor (mainly soft tissue surgery).

A total of 2,071 patients were recruited from the 'Early RA Study' and the 'Early RA Network'. Of these, 2,044 had at least two drug activity states (DAS) recorded between years 1 to 5: 21% were in remission, 15% in low DAS, 26% in low-moderate DAS, 21% in high-moderate DAS, and 18% in high DAS categories. Disease activity was evaluated by calculating the mean DAS28 score for each patient from year 1 (after treatment-onset) to year 5.

Using a statistical model that controlled for numerous factors including age at disease onset, gender, recruitment year, symptom duration, baseline rheumatoid factor, BMI, HAQ , erosions and haemoglobin, patients with low-moderate DAS, high-moderate DAS, and high DAS categories were all predictive of an increased risk of major joint surgery (p<0.005).

However, with respect to intermediate surgery, high-moderate DAS and high DAS predicted a higher risk than those patients with low-moderate DAS or low DAS (p=0.034 and p=0.001 respectively).