Iu Haq

Sheffield risk and treatment table for cholesterol lowering for primary prevention of coronary heart disease

When used for the secondary prevention of coronary heart disease, treatment with an inhibitor of hydroxymethylglutaryl-coenzyme-A reductase results in worthwhile benefit that clearly exceeds any risk in patients whose risk of coronary death is 1.5% or more per year. This evidence can be extrapolated logically to primary prevention of coronary disease provided that treatment is targeted at those with similar or higher risk. We present a table that refines previously proposed methods of risk prediction. The table identifies subjects who have the specified degree of coronary risk; shows the serum cholesterol concentration that confers that degree or risk in the individual; and identifies subjects who will not have this degree of risk, irrespective of their cholesterol concentration. It is simple enough for use in ordinary practice. The table highlights the predominant effect of age on coronary risk; a person who is free of vascular disease and younger than 52 years is unlikely to have the specified degree of risk. Even in older people (60-70 years) several risk factors are generally required to attain this degree of risk. Some people are candidates for lipid- lowering drug treatment with serum cholesterol as low as 5.5 mmol/L, whereas others with cholesterol as high as 9.0 mmol/L are not. Although cholesterol lowering is a powerful method for preventing coronary events in people at high risk, cholesterol measurement by itself is not a good way to identify those with high coronary risk. The method can be adapted readily to target a different level of coronary risk as new evidence on the benefit and risk of treatment becomes available.

The Sheffield table for primary prevention of coronary heart disease: corrected

SIR—We regret that there was an important error in the Sheffield table (Aug 10, p 387), and a corrected version is presented on p 1252. The error in the original was in the table for men only, and arose because the column headings indicating different combinations of risk factors were accidentally transposed as the final table was prepared. Thus the numbers in the table are correct, but do not always correspond to the risk factor combinations shown above them. We are aware that some colleagues have used the table to evaluate individuals, and will want to know what the practical consequences may be. The inaccurate table still predicts, on average, a coronary heart disease (CHD) event rate of 3·0% per year. For eight of the twelve columns in the table for men the risk targeted was acceptably accurate, ranging from 2·8 to 3·2% CHD events per year. Two of the columns would target treatment at men with a lower CHD risk—1·9% and 2·3% per year, respectively. Statin treatment is readily justifiable at this level of risk and this inaccuracy should therefore cause no harm. However, in two columns men were signalled as not needing treatment when their risk of CHD was in fact substantially higher than 3·0% per year—at 3·8% and 4·2% per year. These men should be reassessed by the corrected Sheffield table reproduced overleaf. They can in fact be identified readily, because they are all men with hypertension and left ventricular hypertrophy (LVH) shown by electrocardiography. We therefore suggest that any man with hypertension plus LVH who was assessed by the Sheffield table and not treated should be reassessed with the corrected table. We apologise to colleagues for any inconvenience caused by our error.