ACE inhibitors after myocardial infarction.

LETTERS

Health prevention messages may have paradoxical effect EDITOR,-Correspondence concerning liver failure induced by paracetamol has suggested that education regarding the potential dangerousness of the drug in overdose may prevent deaths."2 Though increased public awareness of this issue may well reduce the number of accidental deaths, recent experience confirms Gary P Bray's fear that it could paradoxically encourage more people to take an overdose.' In addition to being excellent drama, BBC television's long running series Casualty sees itself as having a health education role. To this end, the episode on 9 January sought to highlight the problem of deliberate self harm by paracetamol

overdosage. In the programme a 15 year old girl presented to the accident and emergency department some 48 hours after ingesting about 50 tablets of paracetamol. Her motives were sympathetically presented: she was certainly not suicidal, merely a fairly typical teenage girl with domestic and school stresses. By the time of presentation she had abdominal pain and vomiting. Results of liver function tests were described as being grossly raised, and the programme ended with her having entered a coma and being transferred to the regional liver unit, the casualty consultant clearly stating that she was probably going to die. The subject was handled sensitively and was obviously intended to serve as a deterrent to any adolescent viewers contemplating taking "just a few tablets" to highlight one of the many grievances faced in the average teenager's life. Number of teenage girls presenting after taking overdose, by week, before and after screening of "Casualty" on 93'anuary 1993 Date

Before screening lto7Nov 8to 14Nov 15 to 21 Nov 22 to 28 Nov 29 Nov to 5 Dec 6to 12Dec 13 to 19 Dec 20 to 26 Dec 27 Dec to 2 Jan 3 to 9 Jan

No

No

Date

After screening 2 2 2 3 4

3 1 3 1 2

lOto 16Jan 17to23Jan 24 to 30 Jan 31 Jan to 6 Feb 7 to 13 Feb

14to20Feb 21 to 27 Feb 28 Feb to 6 Mar

7 4 3 5 5 2 2 3

It is difficult to imagine education on this topic being handled more responsibly. Experience in my district general hospital, however, suggests that the programme had the opposite effect: in the weeks immediately following the programme's broadcast we saw a significant increase in the number of teenage girls who presented having deliberately taken an overdose of tablets (paracetamol in all but two cases). In the fortnight immediately after 9 January all

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four of the girls whom I questioned specifically on the subject admitted having seen the relevant episode of Casualty. This hospital's experience is a reminder that those responsible for health promotion must exercise caution when determining the most suitable vehicle for communicating their message, particularly when such an impressionable target audience is concerned. An earlier study did not show a strong imitative effect after a televised parasuicide,4 but perhaps the possibility should not be ignored. SIMON COLLINS

Department of Paediatrics, Alexandra Hospital. Redditch, aWorcestershire B98 7UB 1 Spooner J. Liver failure induced by paracetamol. BM 1993;306: 457-8. (13 February.) 2 Evans J. Liver failure induced by paracetamol. BMJ 1993,306: 717. (13 March.) 3 Bray GP. Liv%er failure induced by paracetamol. B,_ 1993;306: 157-8. (16 Januarv.) 4 Platt S. The aftermath of Angie's overdose: is soap (opera) damaging to vour health? BMJ 1987:294:954-7.

ACE inhibitors after myocardial infarction EDITOR,-The title of Mani A Vannan and colleagues' editorial, "ACE inhibitors after myocardial infarction" was followed by a subtitle which others, like us, might have missed on first reading "may benefit patients with left ventricular dysfunction." The authors conclude that early administration of angiotensin converting enzyme inhibitors "needs further evaluation in high risk subgroups, especially those with large, first anteroapical infarction."' The effects of immediate inhibition of angiotensin converting enzyme or kininase II in approximately 80 000 relatively unselected patients are currently being investigated by the ISIS-4 study (fourth international study of infarct survival) and GISSI-3 (GIuppo Italiano per lo Studio della Sopravivenza nell'Infarcto Miocardico) study.23 In contrast with the CONSENSUS II (cooperative new Scandinavian enalapril survival study) trial,4 treatment is initiated orally, presumably to reduce the incidence of systemic hypotension. However, the combined administration of an angiotensin converting enzyme inhibitor, nitrates, magnesium (ISIS-4 only), streptokinase, and possibly a I adrenoceptor antagonist makes the increased occurrence of early hypotension and subsequent mortality (in a subgroup of patients) a serious concern. In contrast to the CONSENSUS II study most patients in the SAVE (survival and ventricular enlargement) trial had not received treatment with either aspirin or thrombolytic agents at the time of admission.' Also patients were asymptomatic, with left ventricular dysfunction (radionuclide ejection fraction < 40%), free of active ischaemia, and able to tolerate a test dose of captopril. In this group of selected patients, non-acute (average 11 days after acute myocardial infarction, prolonged (average 3 5 years) inhibition of angiotensin converting enzyme or kininase II was beneficial. The rationale for the SAVE study was based on the now much quoted early studies of the beneficial effect of angiotensin converting enzyme inhibitors on "ventricular remodelling" which were performed

in a similarly highly selected group of patients, usually not given thrombolysis, who were particularly predisposed to "remodelling" (that is, those with anterior Q wave acute myocardial infarction). There is therefore little evidence to support the hypothesis that "all" patients with acute myocardial infarction will benefit from such treatment. The AIRE (acute infarction ramipril efficacy) study closed at midnight on 28 February 1993 after recruiting and following up 2006 selected patients with acute myocardial infarction. As in SAVE, though in contrast to the CONSENSUS II, GISSI-3, and ISIS-4 studies, inhibition of angiotensin converting enzyme or kininase II was delayed (3-10 days after acute myocardial infarction. AIRE is unique among the completed or ongoing mortality studies investigating the risks and benefits of delayed inhibition of angiotensin converting enzyme or kininase II, as it selected patients on the basis of clinically diagnosed cardiac failure.6 This approach was influenced by many of the concerns since highlighted in the CONSENSUS II study and expressed in the editorial. However, we continue to hope (as do ,more than 80000 patients) that the enthusiasm of ourselves and other investigators for this mode of therapy has not been misplaced. A S HALL L B TAN S G BALL

Academic Unit of Cardiovascular Studies, University of Leeds, Leeds LS2 9J-F 1 Vannan MA, Taylor DJE, Webb-Peploe M, Konstam MA. ACE inhibitors after myocardial infarction. BMJ 1993;306:531-2. (27 Februarv.) 2 ISIS-4 Collaborative Group. Fourth international study of infarct survival: protocol for a large simple study of the effects of oral mononitrate, of oral captopnrl, and of intravenous magnesium.

AmjCardiol 1991;68:87-lOOD. 3 Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarcto ,Miocardico. GISSI-3 study protocol on the effects of lisinopril, of nitrates, and their association in patients with acute myocardial infarction. AmJ Cardiol 1992;70:62-9C. 4 Swedberg K, Held P, Kjekshus J, Rasmussen K, Ryden L, Wedel L, on behalf of the CONSENSUS II Study Group. Effects of early administration of enalapnrl on mortality in patients with acute myocardial infarction. Results of the cooperative new Scandinavian enalapril survival study II (CONSENSUS II). NEngl7Med 1992;327:678-84. 5 Pfeffer MA, Braunwald E, Moye LA, et al. on behalf of the SAVE Investigators. Effect of captopnrl on mortality and morbidity in patients with left ventnrcular dysfunction after myocardial infarction. Results of the survival and ventricular enlargement

trial. NEnglJMed 1992;327:669-77. 6 Hall AS, Winter C, Bogle SM, Mackintosh AF, Murray GD, Ball SG. The acute infarction ramipnrl efficacy (AIRE) study: rationale, design, organization and outcome definitions. 7 Cardiwvasc Pharnacol 1991 -l8(suppl 2):S 105-9.

EDJTOR,-Much information has accumulated recently on the use of angiotensin converting enzyme inhibitors after myocardial infarction.' Though Mari A Vannan and colleagues put the CONSENSUS II trial (cooperative new Scandinavian enalapril survival study II) into context we want to correct the information given about hypotensive reactions. Treatment in the CONSENSUS II trial was initiated with intravenous enalapril, which caused first dose hypotension in 6-4% of the patients, with more patients developing hypotension in the enalapril group (12% v 3%).2 These patients were at higher risk of subsequent death (1 6% v 9%). In a recent analysis we identified independent predictors of first dose hypotension such as age, use of diuretics, and diastolic blood pressure at

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baseline.3 A risk of hypotension could then be calculated. If the risk of developing first dose hypotension was divided into quarters (from low to high) the incidence of hypotension was 088% and 3-3% in the placebo group versus 4 1/% and 23 -7% in the enalapril group. The corresponding mortality among the same patients, however, was 7/4% and 13-7% in the placebo group versus 8-2% and 15-6% in the enalapril group. These differences are consistent with the overall neutral result of the study and with no significant difference between treatment groups. Thus first dose hypotension after enalapril in this setting seems to identify patients with a high risk of death regardless of enalapril. Early death within 30 days seems to be related to the index infarct and the extent of myocardial injury and is not amenable to enalapril treatment. KARL SWEDBERG

Section of Cardiology, Department of Medicine, University of G6teborg, Ostra Hospital, Goteborg, Sweden JOHN KJEKSHUS

Department of Medicine, National Hospital, University ofOslo, Oslo, Norway 1 Vannan M, Taylor DJE, Webb-Peploe MM, Konstam MA. ACE inhibitors after myocardial infarction. BMJ 1993;306:531-2. (27 February.) 2 Swedberg K, Held P, Kjekshus J, Rasmussen K, Ryden L, Wedel L, on behalf of the CONSENSUS II Study Group. Effects of the early administration of enalapril on mortality in patients with acute myocardial infarction. Results of the cooperative new Scandinavian enalapril survival study II

(CONSENSUS II). NEnglJMed 1992;327:678-84. 3 Kjekshus J, Swedberg K, for the CONSENSUS II Study Group. Importance of first dose hypotension with enalaprilat in acute myocardial infarction. gAm Coll Cardiol 1992;19:206A.

Cardiovascular disease in developing countries

south Asia, and Latin America has a mixture. Pakistan, like most of these countries, is in a phase of epidemiological change: it has a declining incidence of infectious diseases and a rapid increase in non-communicable diseases, especially cardiovascular disease, with the pretransitional diseases like rheumatic heart disease coexisting with posttransitional diseases such as hypertension, ischaemic heart disease, and cardiomyopathies. The increase in the incidence of atherosclerotic coronary heart disease has indeed been phenomenal and can be rightly termed an epidemic, rather than being due to better awareness or improved diagnostic facilities. Ravnskov's presumption that developing countries are likely to have age related coronary heart disease because more people are growing old is not entirely true. Longevity has improved in these countries, but the incidence of coronary heart disease is not always age related. In Pakistan coronary heart disease is becoming more common in the young male population. Westemisation may not be the appropriate term for factors responsible for the increase in cardiovascular disease. Cardiovascular diseases have been labelled as diseases of lifestyles. In Pakistan industrialisation has resulted in mass migration with rapid urbanisation and large segments of populations being catapulted into an era with a highly accelerated pace of life, physical inactivity, and smoking. Dietary change is a part of the new culture and one of the risk factors. No large scale population surveys are available, but existing observational data show that the conventionally established multiple risk factors for cardiovascular disease operate with some variations in the developing world as well. M AFZAL NAJEEB

BMJ Pakistan Edition, Karachi, Pakistan 1 Ravnskov U. Cardiovascular disease in developing countries. BMJ 1993;306: 145-6. (9 January.) 2 Inclen Multicentre Collaboration Group. Risk factors for cardiovascular diseases in the developing world. A multicentre

collaboration study. INCLEN Journal of Clinical Epidemiology

ED1TOR,-The World Health

Organisation's

slogan of 1988-"Heart attacks are developing in the developing countries-prevent them now"was not ill conceived. Developing countries face an epidemic of cardiovascular disease despite Uffe Ravnskov's assertion to the contrary.' The overall pattern of diseases is changing from communicable to non-communicable diseases in the developing world. A multicentre collaborative study in the international clinical epidemiology network recently concluded, "It would appear that many communities in the developing world have high levels of risk factors for cardiovascular diseases and that steps should be taken to prevent the emergence of cardiovascular diseases epidemics in the future."I The 15% mortality from cardiovascular disease in these countries is likely to escalate to 25%, and, according to the World Bank, by the year 2000 cardiovascular disease will be the leading cause of death in many developing countries. A WHO report a couple of years ago stated that the prevalence of hypertension in some groups in developing countries was about the same as that in Finland, which has one of the highest rates of heart disease among the middle aged population. Death certificates may be unreliable, only a fraction of the deaths may be reported, and central registries may be poorly organised with insufficient or incorrect information being fed into them, but enough evidence is available globally to verify the increase in cardiovascular disease in developing countries. Newly industrialising east European countries are experiencing a similar increase in cardiovascular disease. The pattern of. cardiovascular diseases varies in different developing countries. China has a higher incidence of strokes, while hypertension and cardiomyopathies predominate in Africa, ischaemic heart disease is becoming rampant in

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1992;45:841-7.

Informed consent EDITOR,-I agree with D D Kerrigan and others that informed consent is becoming increasingly important in modem surgical practice.' Colleagues and I studied informed consent in 190 patients admitted for a variety of ear, nose, and throat procedures.2 Our patients were randomly allocated to one of four groups, and baseline anxiety was assessed on admission with linear visual analogue scales. Patients in group A were given no further information, while those in group B gave their consent in the usual informal manner. Patients in group C had an information sheet read through with them before signing their consent but were not allowed to read the sheet themselves. Patients in group D were given the information sheet to read at their leisure. A second assessment of anxiety was made four to five hours after the first. Patients in all groups had raised anxiety levels on admission, but only those in group A maintained this higher level. Patients in the other groups reverted to lower anxiety levels. There was no significant difference in anxiety levels between these three groups, which concurs with Kerrigan and colleagues' assertion that the use of information sheets does not raise patients' anxiety. We also found that patients' recall of the proposed procedure improved with use of information sheets. This is important medicolegally because it has been shown that patients frequently forget or mistakenly attribute information to the consent interview.34 Information sheets would provide a permanent record, which could be referred to in the event of a dispute. If information sheets are not

used I suggest that notes should be made at the time of the consent interview detailing the points discussed with the patient. LEONARD O KEEFFE Ear, Nose, and Throat Department, Manchester Royal Infirmary, Manchester M 13 9WL 1 Kerrigan DD, Thevasagayam RS, Woods TO, McWelch I, Thomas WEG, Shorthouse AJ, et al. Who's afraid of informed consent? BMJ 1993;306:298-300. (30 January.) 2 Dawes PJD, O'Keeffe LJ, Adcock SD. Informed consent: the assessment of two structured interview appoaches compared to the current approach. I Laryngol Otol 1992;106:420-4. 3 Byme DJ, Napier A, Cushieri A. How informed is signed consent? BMJ 1988;2%:839-40. 4 Robinson G, Merav A. Informed consent: recall by patients tested postoperatively. Ann Thorac Surg 1976;22:209-12.

EDITOR,-We agree with D D Kerrigan and colleagues that it is time to think again about informed consent.' When patients consent they "approve of, concur, permit, or sanction" actions taken by their medical attendants. Implicit in this is an abrogation of responsibility-to passively permit, not actively decide. They have been advised that this is the best course of action by people who "know better" than they do and therefore, sometimes reluctantly, consent to the operation proposed. Patients' consent can, however, be withdrawn retrospectively or at least challenged. If proof of sufficient information having been given and understood is lacking, the consent form is invalid. We suggest that consent reinforces a paternalistic attitude to patients by the medical staff and does not reflect the reality of contemporary attitudes. Importantly, it also automatically puts medical staff at a disadvantage with regard to medicolegal consequences. Patients come to doctors because something is wrong with them. If an operation is the answer they should be so advised and should simultaneously be informed of the potential complications and risks. If they wish to proceed they should request the medical staff to perform the operation. Request, not consent, should be the patient's responsibility. The medical staff can then agree to the patient's request knowing that both patient and staff know the risks. This issue goes to the heart of our attitudes to patients: we exist to serve the public. They should not have to consent to our actions, they should desire them. If we wish patients to be able to take more responsibility for their health we must give them both the information with which to make such decisions and the opportunity to exercise their rights to make such decisions. We accept that these arguments and indeed this concept of request could not apply to emergencies or to patients of limited intellectual capability. The current practice under these conditions, however, is hardly better. Of what value is informed consent for an emergency caesarean section when the form is signed by a mother who has been having intramuscular pethidine every three hours and breathing 50% nitrous oxide? If we wish to avoid escalating litigation we should welcome such a role reversal. We may still know best, and we still have a duty to our patients, but society now demands that consumers of health care have greater rights and are more informed about their care. By the same token, why should not the medical profession ask that the consumers of health care take on some of the responsibility? Does not every right have a corresponding respon-

sibility? ANDREW LAWSON JULIET COHEN

Woden Valley Hospital,

Canberra, Australia 2600 1 Kerrigan DD, Thevasagayam RS, Woods TO, McWelch I,

Thomas WEG, Shorthouse AJ, et al. Who's afraid of informed consent? BMYJ1993;306:298-300. (30 January.)

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