Is it feasible to plan secondary care services for coronary heart disease rationally? A quantified modelling approach for a UK Health Authority

Background-Coronary heart disease (CHD) is the major cause of mortality in the UK. This paper explores the difficulties facing health authorities in a pplying a rational and needs based approach to the planning of hospital bas ed services and describes a simple model used to bring available informatio n to bear on this problem. Method-Published estimates of CHD incidence were identified and methodologi es were critically appraised. Estimates were extrapolated to a district pop ulation. A three month cohort study of patients with suspected CHD was unde rtaken within a district general hospital and a model of these clinical pat hways was used to examine the volumes of patients and services required to meet the estimated levels of need. Results-From published studies, estimates of CHD incidence ranged from 83 t o 3600 per 100000. From the cohort study, of patients referred with possibl e CHD 62% received a definitive diagnosis of CHD, 56% underwent an exercise EGG, 16% received an angiogram, 4% received a CABG and 2% a PTCA. Using th ese figures together with the cohort study, estimated activity ranges from 247 to 6475 surgical interventions per million population compared with the National Service Framework for Coronary Heart Disease recommendations of 1 500 procedures per million. Conclusions-Current research on CHD incidence gives a very wide variation i n estimated need. This makes its value for service planning questionable an d the model highlights a need for further high quality research. The model provides a link between epidemiological research and secondary care service planning and supports the implementation of recommendations within the Nat ional Service Framework for Coronary Heart Disease.