Rheumatoid arthritis is a chronic disease marked by inflammation in the joints that causes pain, swelling and loss of mobility. It arises from an abnormal immune system attack on the body's own tissue.

Austrian researchers said that although most rheumatologists already recommend early use of so-called disease-modifying antirheumatic drugs in patients with this condition, there was little data comparing the outcome of very early intervention with somewhat delayed intervention in patients with early disease.

They said their study shows there is a definite "window of opportunity" for successful treatment.

In the 3-year study, 20 patients with very early disease who had waited an average of 3 months before being started on drugs were compared with a matched group of 20 patients who had waited 20 months to start therapy.

After just 3 months of treatment, Dr V.P.K. Nell and colleagues at the University Hospital of Vienna and at Lainz Hospital report, patients with early therapy were doing better than those who had waited longer.

This continued over the course of the study, with the early-treatment group showing a disease activity score improvement of 2.8, versus 1.7 for those in the later-treatment group.

And at the end of the study, 70% of patients in the early-treatment group fulfilled American College of Rheumatology criteria for a 20% improvement in disease symptoms, while 40% of those in the later treatment group did. Three years after treatment began, 7 people in the early-treatment group showed evidence of bone damage on x-rays, versus 15 of the later-treatment group patients.

The researchers told the EULAR congress in Stockholm, Sweden, that their results showed that introducing disease-modifying drugs very early "seems highly beneficial in (rheumatoid arthritis) compared with even relatively short delay. Thus, early diagnosis and therapy is the crucial step in achieving better control of disease progression and prognosis in (rheumatoid arthritis)."