Secondary prevention in 24 431 patients with coronary heart disease: survey in primary care

Participants, methods, and results

Practices that had computerised records but had not recently undergone an audit of coronary heart disease were identified from the Pharbase national registry of general practices (IMS Health Strategic Technologies, Loughborough). A total of 653 general practitioners were invited to take part; 548 accepted. Twelve research nurses joined these practices for about four weeks between March 1997 and August 1998. Patients with established coronary disease were identified from practice records and the recording of risk factors and secondary preventive measures was noted.

The mean list size was 7220, with an average of four doctors in each practice. The total practice population was 989 161, representing 1.7% of the population of England, Scotland, and Wales. A total of 24 431 patients had a diagnosis of coronary disease, a prevalence of 45 patients per doctor. The mean age of men was 67 years and that of women was 72. Two thirds of the patients were aged 60-80. The table shows the prevalence of risk factors and secondary preventive drug treatment.

Comment

The Healthwise survey shows that even in well organised general practices there is ample scope for improvement in the detection, recording, and intervention of the major cardiac risk factors among patients with established coronary heart disease. This is the largest survey of secondary prevention of coronary disease in UK general practice in recent years. It may have a bias, representing larger practices with computerised systems in place by 1997.

Several issues are notable. The prevalence of coronary disease was 2.5% in the study; in Britain it is 3-7%. The discrepancy reflects the incomplete data in primary care records. These “lost” individuals are unlikely to receive optimal secondary preventive measures. Patients with established disease in our study were predominantly 60–80 years old, reflecting the ageing and increased survival of the UK population.

Of risk factors in patients with established coronary disease, stopping smoking is the most important action any person can make, yet almost a quarter of the total study population still smoke. Control of blood pressure is reasonably good among people without diabetes, with about two thirds of the overall study population having blood pressure below 160/90 mm Hg. However, blood pressure is less well managed among diabetic patients. We now know that management of blood pressure is at least as important as good control of blood glucose, and better control in these high risk patients is needed.

Lipids were much less well managed than blood pressure. Most patients were hypercholesterolaemic or had never been tested. Only a few were taking statins, despite evidence that these drugs are effective. It is also disappointing that so few patients with a previous myocardial infarction were receiving β blockers, drugs that are proved to reduce ventricular tachycardia and sudden death after a heart attack. It is encouraging that about half of the patients with heart failure in this study were prescribed angiotensin converting enzyme inhibitors.