AUDIT OF AN ANTICOAGULANT CLINIC - DOCTOR AND PATIENT KNOWLEDGE

Oral anti-coagulation with warfarin is increasingly required in the pr ophylaxis and treatment of vascular thrombosis and embolism, Unless th e degree of anti-coagulation is maintained in the narrow therapeutic r ange either serious bleeding or failure to prevent thromboembolism may occur, Complications may occur in up to 31% of patients, We randomly sampled 50 patients attending an anticoagulant clinic and interviewed them, We found the PTR between 2.0-4.0 in 70% patients, Their records indicated that they attended 0.9+/-0.5 times per month, but the patien ts themselves said that they had 2.4+/-1.7 visits per month, lasting o n average 1.9+/-0.7 hours per visit, The mean duration of therapy was 4.3+/-5.4 Sears [range 1 month to 26 years], il Many patients perceive d that they had received no education about warfarin (23%) while the m ajority 67% of the remainder said their doctor had educated them, Conc omitant aspirin was avoided by 74% patients but 14% considered it safe in combination with warfarin; 49% patients believed that alcohol was safe in combination with warfarin, When asked about the colours and st rengths of warfarin tablets, 37% of our sample were completely correct , 9% were completely incorrect and 54% were partly correct, In 16% pat ients they could not describe their current therapy, As doctors may ad just warfarin dosage for patients in terms of tablet colour, we asked a sample of junior doctors about the colours or strengths of warfarin tablets: 10% were completely correct, one doctor knew none of the colo urs or strengths and the remainder had a partial knowledge. These stud ies suggest that the majority of patients on warfarin are cautious abo ut therapy and are safe in their practices, However, we feel that a si gnificant minority may be at risk from complications because of inadeq uate knowledge. We suggest that improving patient understanding by edu cation may reduce complications and lead to more stable control of ant icoagulant therapy.