Analysing the decline in the British Coronary Heart Disease epidemic

Death rates for coronary heart disease (CHD) in the UK have halved since 1980, but CHD is still the commonest cause of death. The decrease since 1980 may be because fewer people now get CHD in the first place, or because more people survive after experiencing CHD, or both. If fewer people now get CHD, this may be due to changes in risk factors in the population (for example, fewer people now smoke). If survival after CHD is better, it will mainly be due to more effective treatment by hospitals or by family doctors, or both. Since 2000, the National Health Service has greatly increased its expenditure on CHD, and the UK spends more per head than any other European country. However most of the spending increase has been concentrated on facilities for people in hospital with CHD. It is therefore important that we understand the main reasons why CHD has fallen in the last two decades. Then government departments will be able to make informed choices about how they best allocate future expenditure, to bring about further decreases in deaths due to CHD. We will analyse three data sets; (i) the British Regional Heart Study which has followed up over 7000 British men for 25 years; (ii) the General Practice Research Database (and the similar THIN database), which has captured computer-recorded information on patients from hundreds of general practices since 1990, and (iii) the Health Survey for England (HSE), which surveys about 19,000 people every year, and in 1994, 1998 and 2003 concentrated on issues concerning cardiovascular disease. From these studies, we will describe trends in heart disease rates, in risk factors, treatment rates, and survival rates after heart disease. Using a computer model called IMPACT, we will then estimate the contribution of changes in risk factors, and increases in treatment, in decreasing the CHD epidemic. We will work with the National Heart Forum, a well-established and influential advocacy group concerning government health policy, to help guide our analysis, and to disseminate our findings.

Mortality for coronary heart disease (CHD) in the UK has halved since 1980, but CHD is still the commonest cause of death. The decrease since 1980 may be due to lower incidence of CHD, or because of better survival and prognosis after CHD, or both. Lower incidence may be due to changes in risk factors in the population: for example, the decline in smoking. Improved prognosis following CHD will mainly be attributable to wider use of proven treatments in secondary and primary care. Since the publication in 2000 of the National Service Framework for CHD, health service expenditure on CHD has greatly increased, and the UK now spends more per head than any other European country. However most of the spending increase has been concentrated on treatment for CHD, in particular on an expansion in revascularisation services. It is therefore important that we understand the main reasons why CHD has fallen in the last two decades. Then government departments will be able to make evidence-based choices concerning resource allocation, to bring about further decreases in CHD mortality. We will analyse three data sets; (i) the British Regional Heart Study which has followed over 7000 British men for 25 years for CHD incidence and has collected physical and biochemical measures, and has administered seven questionnaires concerning health status, use of treatment, health behaviour etc; (ii) the General Practice Research Database (and the similar THIN database), which has captured computer-recorded information on consultations by patients from over 700 general practices since 1990, and (iii) the Health Survey for England (HSE), which annually surveys about 19,000 people, and in 1994, 1998 and 2003 concentrated on cardiovascular disease. From these studies, we will describe trends in CHD, in risk factors, treatment rates, and survival rates after CHD. In particular we will evaluate the relationship between risk factor changes, treatment and trends in CHD. Using the established IMPACT model, we will then estimate the contribution of changes in risk factors, and increases in treatment, in decreasing the CHD epidemic. We will work with the National Heart Forum, a well-established and influential advocacy group concerning government health policy, to help guide our analysis, and to disseminate our findings.