HDL-cholesterol and cardiac disease: which table to use?

Interventions to modify cardiovascular risk factors have the greatest benefit in individuals at greatest risk of a cardiovascular event, not necessarily those with the most extreme levels of any particular risk factor. Patients with vascular disease are readily identified, but risk calculation in those without disease provides a way of integrating several risk factors to identify individuals at greatest risk. Equations have been derived from different epidemiological studies (Framingham, PROCAM, etc.) to estimate the risk of different clinical end-points [coronary heart disease (CHD) or cardiovascular disease (CVD)]. Some algorithms have been adapted to produce risk charts' or 'tables'; others have been modified to incorporate additional risk factors. Current UK guidelines all endorse calculation of CHD risk using the Framingham algorithm. This predicts risk well for some North European populations but less reliably in low-risk populations. It does not incorporate some risk factors, including serum triglycerides, family history, C-reactive protein, or homocysteine. Risk calculation should not be used in those with evidence of vascular disease, genetic hyperlipidaemia or a strong family history of CHD, and should be interpreted with caution in non-Caucasians. Measurement of high-density lipoprotein (HDL)-cholesterol is essential for accurate risk calculation. This has significant cost and workload implications for the laboratory. The way a laboratory reports results should be designed in such a way as to facilitate simple and accurate risk calculation.