Aim: To investigate whether a risk score proposed by the British Regional Heart Study (BRHS), derived from data collected in 1978-1980, provides an appropriate basis for current coronary risk factor screening and intervention in general practice.
Methods: The BRHS risk score was applied to 1993 men aged 40-59 years and 1353 women aged 35-59 years, from 13 general practices in England, Wales and Scotland, who had health checks during 1991-1992 in the British Family Heart Study (FHS). Modifications to the BRHS risk score were made in order to identify subjects with a current high risk compared with others of the same age and sex. These were validated on 3272 men and 2229 women recruited from different general practices during 1992-1994 in the FHS.
Results: Only 9% of men in the FHS fell into the published top (highest risk) quintile of the BRHS score, versus an expected 20%, and 44% fell into the bottom quintile. Scores were, on average, substantially lower in the FHS men than in the BRHS men, principally because of lower measured cholesterol levels (using a Reflotron) and a lower prevalence of cigarette-smoking. The BRHS scores also tended to increase with age, disproportionately identifying older subjects, and were substantially lower in women than in men. Simple age-related modifications to the risk score were therefore devised to overcome these problems. These modifications performed well in the validation.
Conclusions: The substantial difference in risk scores between the BRHS and FHS men may reflect both a real reduction in risk and changes in calibration and methodology. Current use of the BRHS risk score may therefore mislead doctors and patients in the direction of complacency. In addition, the published BRHS risk score has an age-dependence that is undesirable in terms of guiding the intensity of lifestyle intervention which should be offered to an individual patient. The simple modifications proposed provide a more appropriate basis for coronary risk factor screening and intervention in general practice, and one that can be used both for men and for women.