University of Oxford, Oxford, UK.
Around the time of publication of this paper1 there was growing discussion of the need for GPs to extend their role and become more proactive. Until then, the function of the GP was generally considered to be confined to treatment of the sick. Even such things as antenatal care, child health and immunization were largely the responsibility of public health; and screening was no part of the GP's work; nor was health education (health promotion had yet to be invented). Butparticularly after the landmark GP Charter2 of 1965 which encouraged the development of primary care teams through reimbursement of costs of practice premises and staffprogressive practices were taking on public health roles and moving into preventive work.3
This change was stimulated by a Government publication4 Prevention and health: everybody's business which emphasized the importance of lifestyle as a contributor to ill-health, particularly cardiovascular disease. It called for action by individuals and health professionals and for a reorientation of local and national health services to place greater emphasis on prevention both through activities at a population level and by better identification and management of high-risk individuals.
It was this issue of high-risk screening which the South-East London Screening Study had addressed in a randomized trial initiated in the mid-1960s. The trial had investigated the effect of inviting middle-aged patients in two large London general practices to a screening clinic where a health questionnaire was administered, a physical examination conducted and a battery of tests carried out. In essence, little of importance was found at the clinic which was not already known to the general practitioner. Over 9 years of follow-up no significant differences were found between Screening and Control groups in reported symptoms, GP consultation rates, hospital admissions, certified sick absence or mortality. It was therefore concluded that this multiphasic screening conferred no health benefit and that general practice check-ups could not be justified. But it was also acknowledged that case-finding might have been effectiveand that 93% of participants would have been eligible for this, having attended the practice for other reasons during the follow-up period.1
However, uncertainties about general practice health checks continued and in 1981 the Royal College of General Practitioners published a report5 Prevention of Arterial Disease in General Practice which called for an active case-finding/ opportunistic screening approach to detection and management of cardiovascular risk. This led to an evaluation6,7 of its recommendations and to two further large randomized controlled trials of cardiovascular risk screening and intervention in general practicethe OXCHECK Study810 and the Family Heart Study.11,12
These studies investigated nurse-conducted screening and intervention in middle-aged patients in about 30 practices in all. At one-year follow-up both studies found small but significant reductions in blood pressure and cholesterol levels, compared with controls, and in the case of the OXCHECK Study the effect was sustained at the planned 3-year follow-up.10 An estimated 12% overall cardiovascular risk reduction was achieved in the Family Heart Study and a similar reduction in OXCHECK. Although the effects of these interventions were modest it was considered that their public health significance would be substantialbut that the workload involved and the resource implications would be great and probably not acceptable and feasible.13
Further doubt has been cast on the value of cardiovascular risk screening by a recent systematic review14 of randomized controlled trials of multiple risk factor interventions for preventing coronary heart disease which included a meta-analysis of 14 trials. It concluded that the pooled effects of multiple risk factor intervention on morality were insignificant and that changes in risk factors were modestand that fiscal and legislative measures might be more effective.
While debate continues about the role of general practice in primary prevention, the strong evidence base for secondary preventionparticularly pharmacological interventionsin those with established vascular disease has shifted the focus. Audits15 show a major deficit in the implementation of measures of proven effectiveness in such patients and, in England, the recently published National Service Framework16 emphasizes the priority which this issue should receive at the individual patient level in primary care. But it must be emphasized that such measures can only, however, be supplementary to a fiscal, public policy and public health approach at a population level which offers the major potential for cardiovascular disease prevention.17
References
1 The South-East London Screening Study Group. A controlled trial of multiphasic screening in middle-age: results of the South-East London Screening Study. Int J Epidemiol 1977;6:35763.[Abstract]
2 British Medical Association. Charter for the Family Doctor Service. London: BMA, 1965.
3 Tudor Hart J. A New Kind of Doctor. London: Merlin Press, 1988.
4 Department of Health & Social Security. Prevention and Health: Everybody's Business. London: HMSO, 1978.
5 Royal College of General Practitioners. Prevention of Arterial Disease in General Practice. Report from General Practice 19. London: RCGP, 1981.
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9
Imperial Cancer Research Fund OXCHECK Study Group. Effectiveness of health checks conducted by nurses in primary care: results of OXCHECK study after one year. Br Med J 1994;308:30812.
10
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11
Wood DA, Kinmonth AL, Pyke SDM, Thompson SG on behalf of the Family Heart Study Group. A randomised controlled trial evaluating cardiovascular screening and intervention in general practice; principal results of the British Family Heart Study. Br Med J 1994; 308:31320.
12 Wood DA, Kinmonth AL, Davies G et al. on behalf of the British Family Heart Study Group. Cardiovascular risk factors in the Family Heart Study. A national randomised controlled trial evaluating cardiovascular screening and interventions in British general practice. Br J Gen Pract 1994;44:6267.[ISI][Medline]
13 National Heart Forum. Preventing Coronary Heart Disease in Primary Care: The Way Forward. London: HMSO, 1995.
14
Ebrahim S, Davey Smith G. Systematic review of randomised controlled trials of multiple risk factor interventions for preventing coronary heart disease. Br Med J 1997;314:166674.
15 ASPIRE Steering Group. A British Cardiac Society survey of the potential for secondary prevention of coronary heart disease. Heart 1996;75:33437.[Abstract]
16 Department of Health. Coronary Heart Disease: Modern Standards and Service Models. London: Department of Health, 2000.
17 Rose G. The Strategy of Preventive Medicine. Oxford: Oxford University Press, 1992.