Prophylactic treatment after myocardial infarction in primary care: how far can we go?

Despite best practice, it may not be achievable in some patients to reach the optimal goals of secondary prevention recommendations for various reasons, such as co-morbidity, contraindications for some drugs or side effects.

Our aim was to estimate the achievable standards for audit purposes in primary care for prophylactic treatment of secondary prevention of myocardial infarction.

We conducted a survey of consecutive patients with a hospital diagnosis of first acute myocardial infarction during 1997 who were identified from discharge books from four hospitals and interviewed at their primary health centre 2 years after admission. The achievable standard for a prophylactic drug was then defined as the proportion of patients that could benefit from the treatment excluding those that for one justified reason or another were off medication.

Three hundred and sixty-nine patients were interviewed in the follow-up. Aspirin or another antiplatelet regimen was prescribed in 86.9 patients, beta-blockers in 50.2%, angiotensin-converting enzyme (ACE) inhibitors in 32.5% and lipid-lowering drugs in 52%. The estimated achievable standards for those prescribed drugs were 94.5, 71,8, 50.5 and 69.8%, respectively.

There is an underuse of prophylactic drug therapies after myocardial infarction. The standards established in this study for secondary preventive drug treatment might be achieved through a reasonable effort by GPs working in primary care committed to improving the quality of care.