Evaluation of a computer-based decision support system for treatment of hypertension with drugs: retrospective, nonintervention testing of cost and guideline adherence

Objective. To evaluate a computerized decision support system (DSS) for dru g treatment of hypertension, regarding quality, safety, and cost compared t o actual antihypertensive drug treatment. Design. The medical profiles of 338 hypertensive patients treated with drug s against hypertension were processed by the DSS. The drug treatment propos ed by the system was then compared to actual treatment given by their physi cian. Setting. Four health centres in the county of Vasterbotten, in Sweden. Subjects. A List of hypertensive patients was extracted from the computeriz ed medical records of each health centre and every fifth patient's medical profile was assessed by the system. Interventions. None. Main outcome measures. Drug used, drug used in relation to certain major di seases such as diabetes mellitus, asthma, ischaemic heart disease (MD), and previous myocardial infarction. Adherence to hypertension guidelines, safe ty, and cost. Results. The DSS suggested significantly more thiazides and significantly f ewer calcium antagonists than the physicians had prescribed, with a total c ost reduction of 33-40%, depending on doses chosen. The DSS drug profile wa s more adherent to guidelines in patients with major complicating diseases, suggesting an improvement in treatment quality for these patients by the D SS. Conclusion. The DSS which fully implements current guidelines may improve t he quality of antihypertensive treatment, concurrently leading to a conside rable reduction in drug costs.