Current disease management in rheumatoid arthritis (RA) has moved towards "inverting the therapeutic pyramid" by introducing disease-modifying anti-rheumatic drugs (DMARDs) early. Despite the logic of early DMARD therapy, there is a dearth of supportive evidence for this approach. We report a randomised controlled trial comparing sulphasalazine monotherapy with diclofenac monotherapy in early RA. The primary aim was to provide unequivocal evidence that early DMARDs prevent erosive damage. The secondary aim was to evaluate if sulphasalazine used alone has comparable symptomatic benefits to NSAIDs.
117 patients with RA for under 12 months of diagnosis (mean 2 months) were randomised (62 sulphasalazine; 55 diclofenac). Sulphasalazine patients comprised 76% women, and 58% were rheumatoidfactor positive. Diclofenac patients comprised 74% women, and 54% were seropositive. 36% completed 12 months of therapy (16 sulphasalazine; 26 diclofenac); sulphasalazine was given for a mean period of 21 weeks and diclofenac for a mean period of 33 weeks. Results were analysed on an intention to treat basis.
After 12 months the mean number of new erosions in patients randomised to receive sulphasalazine was 2.0 (95%CI 0.9, 3.1) and in patients randomised to receive diclofenac was 7.5 (95%CI 4.1, 10.9; p = 0.002 by Student's unpaired t-test). An analysis of valid compliant completers showed the mean number of new erosions in patients who received 12 months therapy with sulphasalazine was 2.3 (95%CI 0.6, 4.0) and in patients who received 12 months diclofenac was 10.5 (95%CI 5.0, 15.9; p = 0.018 by Student's unpaired t-test). The Ritchie articular index, swollen joint counts and pain scores decreased with both sulphasalazine and diclofenac, with mean falls in both groups of 15-20% at 2 weeks and 30-40% at 4 and 8 weeks. There were no differences between treatments. Disease activity scores showed similar highly significant mean decreases within both treatment groups (P < 0.001 in all cases) of 0.5 at 2 weeks and 1.0 at 4 weeks; at 12 and 26 weeks they were significantly lower with sulphasalazine (p = 0.036 and 0.045). 75% of the patients given sulphasalazine and 65% of those given diclofenac had one or more adverse events with no major differences between treatments.
These results show that an accelerated dosing schedule of sulphasalazine has identical effects to diclofenac in reducing symptoms, indicating it is a rapidly effective DMARD. They also provide unequivocal evidence, analysed on an intention to treat basis, that early treatment with sulphasalazine significantly reduces the extent of radiological progression in active RA.