EDITORIAL

Screening for cardiovascular risks - in whose interest do we act? Heinz-Harald Abholz

The answer seems to be easy: We do screening for our pa- tients. But easy answers quite often are false answers. Con- sidering only those risks which can be treated, we have re- gard to blood pressure, smoking, body weight, lack of ex- ercise, stressful life-style and cholesterol. Only blood pres- sure and smoking can be treated with the effect of reduced morbidity and mortality - here screening is worthwhile. For body weight, exercise and life-style no therapeutic regime has been proved to be effective in reducing morbidity and mortality.’~’ Even if this might be partly due to ineffective studying, we have to accept this till there is other evidence. For cholesterol the situation is much more complex. In sec- ondary prevention it seems that treatment is effective: even if the effect is not as important as the propaganda would indicate. The Scandinavian 4-S-Study has shown that under cholesterol reducing treatment with simvastatin to- tal mortality could be reduced by 30%.‘ But these 30% correspond to 3.7% lifes saved in a period of six years (sur- vival 87.6 vs 91.3% in six years). For secondary prevention we do not need screening. We know our patients who have had a myocardial infarction, stroke etc. In primary prevention, for which screening is used, choles- terol lowering treatment is only able to reduce specific, i.e. cholesterol-induced, but not total morbidity and mortal- it^.'.^.' There is no study demonstrating that less people die taking cholesterol reducing drugs or following a diet.8 But dying and getting ill have to be important indicators on which a GP decides on screening and treatment. These crit- eria are also what concerns our patients. The question of cholesterol-screening and treatment in primary prevention is more complicated by the fact that from a meta-analysis it seems that persons at high risk, having several risks and a very high cholesterol, might also have a reduced total mortality under cholesterol- lowering medi~ation.~ Here we have come to one of the main problems of screen- ing: In primary prevention, the reduction in total morbid- ity and mortality (true for blood pressure and smoking; possibly true for only high risk persons with a high choles- terol) have to be differentiated. For those with a strongly

Heinz-Harald Abholz, general practitioner, lecturer in general practice, lecturer in public health. Free University of Berlin, Universitatsklinikum Rudolf Virchow in der Cbarite, Apostel-Faulusstrasse 39, 10823 Berlin, Germany.

developed risk, treatment brings a lot of benefit - but these individuals are a small minority of those at risk at all.

For those with a mildly developed risk, treatment provides no or only a small advantage, but they are the majority of those at This is of great importance, because the benefit even those at high risk can expect, is not very great. Considering the Lipid Research Clinics data on persons with a least 265 mg% cholesterol a t entrance, the 7-years specific mortality and morbidity was 8.6 vs 6.9YO.l’ This means that 1.7% benefited; but 98.3% were under treat- ment without any benefit to themselves: They would not suffer any cholesterol-mediated disease or if they did, it was in spite of treatment. This way of seeing - in absolute, not in relative terms - is what we need as GPs. This is the only way of answering the questions patients have. For them it would be ridiculous to submit to life-long treat- ment and medicalisation for little or no advantage. It be- comes the more ridiculous and outside a patient’s life- orientation the lower we set the intervention point, e.g. 220 mg cholesterol, 95 mmHg diastolic blood pressure. This may explain why there are no studies showing relevant bet- ter control of risks in screening groups compared to non- screening groups.”- So we are - as Rose called it - in a preventive dilemma: If we want to be successful on the public health level, we have to treat all at risk, even and especially those with mildly de- veloped r i~ks . ’~ They give rise, as the majority, to the bur- den of risk-induced diseases. By doing so, we ignore the unwritten patient-doctor contract according to which the patients can expect us to act in their best interest. Seeing the very small advantage most of our patients at risk would have and knowing about the side-effects, and the potential harm of treatment, we quite often cannot decide in favour of treatment. We should decide against screening if we are not going to treat. Because screening in itself, even for those without an abnormal finding, can be harmful: Screening produces an atmosphere of anxiety, people under screening are brought into the world of constant threat. The feeling of health and happiness is always spoiled by knowing that only screening is able to control whether or not one is still healthy. If we are successful in implementing a lot of screening programmes, we will build up such a life-experience of being under threat. There are studies showing that screening has such an effect.I6-l8 But there are more side effects: Screening can produce dis- ease where there is no illness. Some individuals develop a

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EDITORIAL

fixed idea that an irrelevant cholesterol or blood pressure elevation etc. is the reason for their bad feelings, they pro- duce somatisation on cholesterol, or blood pressure et~.’~.’’ Also there are the side effects we have to expect from diet and drugs, which iRdicate to the person following treat- ment that he or she is an invalid, is not perfect. Finally we have to see that treatment of risk factors always gives rise to the possibility of drug side effects for all under treatment and benefit for only a few. So, what should we do? I think we should not follow screening programmes. Individually we should decide with and for a particular patient, what is the best way for her or him. With this kind of policy we will miss a few of our patients a t high risk. But this kind of policy prevents us harming more of our patients, who would not have any benefit from screening, but would be at risk of being harmed.

From a public-health point of view this policy is mayhem: Only the smallest segment of the burden of risk-induced diseases will be prevented - resulting in irrelevant changes in general morbidity and mortality. We as GPs are in the very difficult position of deciding between the public’s health and patient’s interests. For me the answer a GP has to give seems to be quite evident - even if society tries to change our pattern of care from the in- dividual patient to society.

References Hudson TW. Exercise. In: Hudson TW, Reinhart MA, Rose StD, Stewart GK. Clinical preventive medicine. Boston, Toronto: Little Brown, 1988: 431-8. Kornitzer M. Changing individual behaviour. In: Marmot M, Elliott P, editors. Coronary heart disease epidemiology - from aetialogy to public health. Oxford: Oxford University Press, 1992: 482-94. Have1 RJ, Rapaport E. Management of primary hyperlipidemia. N Engl] Med 1995; 332: 1491-8. Scandinavian Simvastatin Survival Study Group. Randomised trial of

cholesterol lowering in 4,444 patients with coronary head disease. Lancet 1994; 344: 1383-9.

5 Oliver MF. Reducing cholesterol does not reduce mortality. J Amer Coll Curdioll988; 12: 814-7.

6 Garber AM, Sox HC, Littenberg B. Screening asymptomatic adults for cardiac risk factors: the serum cholesterol level. Ann Intern Med

7 The Toronto Working Group on Cholesterol Policy. Asymptomatic hypercholesterolemia: a clinical policy review.] Clin Epidemioll990; 43: 1021-121.

8 Davey Smith G. Primarpravention und Sekundarpravention: Die Re- levanz des koronaren Gesamtrisikos fur die Effectivitat einer Cho- lesterinsenkung das Problem der nichtkoronaren Effekte. In: Borg- ers D, Berger M, editors. Berlin-Wien: Blackwell, 1995; 84-101.

9 Davey Smith G , Song F, Sheldon TA. Cholesterol lowering and mor- tality: the importance of considering initial level of risk. Br Med J

10 Miall WE, Greenberg G. Mild hypertension: is there pressure to treat? Cambridge: Cambridge University Press, 1987.

11 Woolf St H. Elevated serum cholesterol in asymptomatic adults. In: Goldbloom RB, Lawrence RS, editors. Preventing disease: beyond rhetoric. New York: Springer, 1990; 401-11.

12 Lipid Research Clinics Program: Reduction in incidence of coronary heart disease.]AMA 1984; 251: 351-64.

13 D’Souza MF. Early diagnosis and multiphasis screening. In: Bennett AE, editor. Recent advances in community medicine. Edinburgh: Churchill Livingstone, 1978; 195-214.

14 Field K, Throgood M, Silagy C, Normond C, O’Neill C, Muir J. Strat- egies for reducing coronary risk factors in primary care: which is most cost effective? Br Med J 1995; 310: 1109-12.

15 Rose G. The strategy of preventive medicine. Oxford: Oxford Uni- versity Press, 1990.

16 Haynes RB, Sackett DL, Taylor DW, et al. Increased absenteism from work after detection and labelling for hypertensive patients. N Engl JMed 1978; 299: 741-4.

17 Jachuk SJ. The effect of hypotensive drugs on the quality of life.] Roy Coll Gen Pruct 1982; 32: 103-5.

18 Martheau ThM. Psychological costs of screening. Br Med J 1989; 299: 527.

19 Schafstedde F. Zur Bedeutung der Cholesterinkontrollen im Artzt- Patienten-Verhaltnis. Allgemeinmed 1994; 70: 942-6.

20 Abholz HH. Cholesterin: Medizinische Indikation und Symbolgehalt - eine Praxisanalyse. Allgemeinmed 1995; 71: 310-21.

1989; 110: 622-39.

1993; 306: 1367-73.

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