Causes of DMARD withdrawal following ADR within 6 months of initiation among Indian rheumatoid arthritis patients

The present study was conducted in Indian rheumatoid arthritis (RA) patients prescribed disease-modifying anti-rheumatic drugs (DMARDs) to determine the incidence and type of adverse drug reactions (ADRs) leading to their withdrawal in the initial 6 months of therapy. This was considered important as pharmacogenetic variations in the pattern of RA in different populations and genetic differences in efficacy and safety to drugs demand separate studies to be conducted in different populations. Hospital records were used to identify 1,000 consecutive patients with RA fulfilling the American College of Rheumatology criteria and having at least 6-month follow-up. Age, gender, duration of arthritis, drug usage and ADR-related drug withdrawal were recorded from the charts. Most of the patients were put on single DMARD. Combined use of DMARD was less frequent and non-use of DMARD was common; however, disease control was good. The commonest DMARD used in our hospital was hydroxychloroquine 444 (44%) and the commonest combination used was methotrexate with hydroxychloroquine by 55 (6%). Sulphasalazine use showed preference to young and males. Supportive drugs used were NSAIDs by 883 (88%), corticosteroids by 646 (65%), paracetamol by 594 (59%) and amitriptyline by 88 (9%). Incidence of ADR-related DMARD withdrawal was maximum with leflunomide 2/15 (13.33%) followed by methotrexate 9/116 (7.76%), sulphasalazine 6/185 (3.24%), chloroquine 3/131 (2.29%) and hydroxychloroquine 8/444 (1.8%). Severity and symptomatology of disease, genetic pattern of patients, financial status, previous experience of the clinicians and patients, availability of drugs, patient expectations and compliance were the main factors that lead to a difference in pattern of therapy in our patients compared to other population.