Coronary risk estimates and decisions on lipid-lowering treatment in primary prevention: comparison between general practitioners, internists, and cardiologists.

Background: Quantitative assessment of an individual's absolute cardiovascular risk is essential for primary prevention. Although risk-scoring tools have been developed for this task, risk estimates are usually made subjectively. We investigated whether general practitioners (GPs), internists and cardiologists differ in their quantitative estimates of cardiovascular risk and their recommendations about lipid-lowering treatment for the same set of patients.
Methods: Mail survey. Nine written clinical vignettes, four rated high-risk and five rated low-risk according to the Framingham equation, were mailed to 90 randomly selected GPs and to the same number of internists and cardiologists in Sicily. The doctors were then asked to estimate the 10-year coronary risk in each case and to decide whether they would recommend a lipid-lowering treatment.
Results: In the majority of the nine cases, the cardiologists' risk estimates were significantly lower than those of the other two groups. A higher proportion of internists (mean value 0.68) decided to start treatment than GPs (0.54) or cardiologists (0.57). In all three groups, the doctors' willingness to begin treatment was over 90% when their risk estimate was above 20%, and less than 50% when it fell below this level. Internists were more prone to treat than the other two groups even when their patients' estimated risk was below 20%.
Conclusion: When presented with the same set of clinical cases, GPs, internists and cardiologists make different quantitative risk estimates and come to different conclusions about the need for lipid-lowering treatment. This may result in over- or under-prescription of lipid-lowering drugs and inconsistencies in the care provided by different categories of doctors.