Measurement of clinical response to anti-inflammatory drug therapy in rheumatoid arthritis.
In order to assess the relative merits of different assessment methods in rheumatoid arthritis, a double-blind, crossover clinical therapeutic trial was carried out in 37 ambulant hospital inpatients with ‘definite’ or ‘classical’ rheumatoid arthritis, as defined by the American Rheumatism Association. The patients all had longstanding rheumatoid arthritis and had received various drug therapies prior to the trial, including in some patients oral corticosteroids and crysotherapy.

In addition to placebo each patient received orally sodium salicylate 1 g four times a day, indomethacin 25 mg four times a day, ibuprofen 400 mg three times a day, and prednisolone 2.5 mg four times a day. Each treatment was given for a period of one week, and the patients were assessed at the end of each treatment week by the same physician.

Assessments included grip strength, digital joint circumference, an articular index of joint tenderness, clinical knee scores of joint inflammation, and 99mTc knee joint uptakes. The amount of pain the patients had in their joints was also recorded. The results showed that all four active drugs produced a response measurably better than placebo, but comparison between the four active drugs showed no conclusive evidence that any one drug was superior to the other three active drugs. The assessment methods which best reflected active drug response were the patients' assessment of the pain in their joints and the articular index of joint tenderness.

The 99mTc knee joint uptakes gave results comparable to the clinical scores of knee joint inflammation, and clearly reflected differences between active drugs and placebo. Grip strength proved useful, but was a less sensitive index. Digital joint circumference proved to have no discriminating power.