ARE SLOW-ACTING ANTIRHEUMATIC DRUGS MONITORED TOO OFTEN - AN AUDIT OFCURRENT CLINICAL-PRACTICE

Rheumatologists usually recommend monthly blood monitoring when patien ts with rheumatoid arthritis (RA) are treated with slow-acting anti-rh eumatic drugs (SAARDs). Is monthly monitoring needed or could its freq uency be reduced? We audited the opinions of UK rheumatologists and re viewed clinical experience at three centres. To ascertain the interval at which patients are monitored and the determinants of monitoring po licy we sent a questionnaire to 193 consultant rheumatologists; 143 (7 4%) replied. The majority use monthly monitoring for most SAARDs excep t sulphasalazine, chloroquine and hydroxychloroquine. There is extensi ve variation, which is not related to the type of rheumatology unit or whether a shared scheme with general practitioners is used. Reviewing experience in 390 patients treated with SAARDs at three adjacent rheu matology units in London showed that haematological adverse reactions were infrequent. During 1560 patient-years of treatment involving 18 7 20 monthly monitoring visits there were 13 haematological adverse reac tions(ll thrombocytopenias and two leucopenias). Five thrombocytopenia s occurred in the first 6 months of therapy; two were gradual and thre e developed more rapidly over 1-2 months. Six thrombocytopenias develo ped after 6 months of treatment; five occurred gradually over 5 months or more and one borderline low platelet count was seen once. The two leucopenias were borderline low white cell counts occurring gradually over 3-6 months. Such frequent monitoring is expensive. The total cost of monitoring 390 patients for 1560 patient-years was $420 000. The c ost of detecting each adverse reaction was $32 000. Three-monthly moni toring when therapy is established after an initial stabilizing period would have identified seven out of eight late adverse reactions. Moni toring policies are mainly based on clinical consensus with few prospe ctive studies of their value; they need re-evaluation.