after causing neuropathy.9 In contrast, patients with leprosy are not being warned about the dangers and sensory electrophysiological testing is not being done, precluding early detection and possible recovery after withdrawal of the drug. It is inexplicable why leprologists cannot carry out a simple clinical examination of the nervous system before administering thalidomide. It is a mistake to assume that nerve damage is already present in erythema nodosum leprosum: in 10 out of 14 patients whom I managed no signs of a polyneuropathy were present, according with the natural course of the disease.' Drug toxicity to the nervous system cannot be excluded now that it is admitted that neuropathy in lepromatous leprosy may mask the effects of thalidomide neuropathy and means also that thalidomide cannot now be claimed to prevent nerve damage. The ulnar mononeuritis sometimes accompanying erythema nodosum leprosum may fail to respond to thalidomide.9 High dose corticosteroids can be avoided in the management of erytheina nodosum leprosum, a condition that is not serious. As amyloidosis occurs in untreated lepromatous leprosy the lack of progression could also have occurred in treated patients without erythema nodosum and cannot be attributable to thalidomide.'° C L CRAWFORD
Department of Anatomy, Charing Cross and Westminster Medical School, London W6 8RF 1 Waters MFR. Use of thalidomide in leprosy. BM,J 1991;303: 470. (24 August.) 2 WHO Expert Committee on Leprosy. Sixth report. WHO Tech Rep Ser 1988;No 768. 3 Swift TR, Sabin TD. Leprous neuritis. In: Swash M, Oxbury J, eds. Clinical neurology. Edinburgh: Churchill Livingstone, 1991:1236-43. 4 Knop J, Bonsmann G, Happle R, Ludolph A, Matz DR, Mifsud EJ, et al. Thalidomide in the treatment of 60 cases of chronic discoid lupus erythematosus. Brj Dermatol 1983;108:461-6. 5 Hess CW, Hunziker T, Kupfer A, Ludlin HP. Thalidomide induced peripheral neuropathy. J Neurol 1986;223:83-9. 6 Heney D, Norfolk DR, Wheeldon J, Bailey CC, Lewis IJ, Barnard DL. Thalidomide treatment for chronic graftversus-host disease. Br7 Haematol 1991;78:23-7. 7 Crawford CL. Treatment of erythema nodosum leprosum with thalidomide. Lancet 1973;ii:567-8. 8 Crawford CL. Nature of the sensory loss in leprosy. Muscle Nerve 1988;11:276-7. 9 Levy L, Fasal P, Levan NE, Freedman RI. Treatment of erythema nodosum leprosum with thalidomide. Lancet
increased their sample size by adding a further three positive cases at the end of the study; would they have done this if the results had not supported their hypothesis? The sample size nevertheless remains inadequate. The 95% confidence interval for the detection rate extends from 39% to 94%. Such an imprecise estimate is inadequate stipport for the authors' conclusions. Finally, the authors do not take account of the psychological consequences of screening.4 We would argue that the main cost of a serological screening programme is not directly measurable in terms of money. Rather, it consists of the worry inflicted on all mothers by forcing them to consider at length the risk of their fetus suffering from Down's syndrome. Two constructive points, nevertheless, emerge. Firstly, if a pregnant woman is already sufficiently worried about the prospect of Down's syndrome to proceed to the inconvenience and risk of amniocentesis she may ethically be offered serological screening for Down's syndrome. Presumably a large proportion of pregnant women over 35 would fall into this category. Secondly, an unanswered scientific question relating to serological screening for Down's syndrome is the psychological impact on the women tested. A formal trial would help to estimate the likely psychological cost of a national screening programme.5 R M KEATINGE E S WILLIAMS
Department of Public Health Medicine, Croydon General Hospital, Croydon, Surrey CR9 2RH 1 Lewis M, Faed MJW, Howie PW. Screening for Down's syndrome based on individual risk. BMJ 1991;303:551-3. (7 September.) 2 Keatinge RM, Williams ES. Prenatal screening for Down's syndrome. BMJ7 1991;303:54-5. (6 July.) 3 Pauker SP, Pauker SG. The amniocentesis decision: ten years of decision analytic experience. March of Dimes Birth Defects Foundation, Birth Defects; Original Article Series 1987;23: 151-69. 4 Marteau T. Reducing the psychological costs. BMJ 1990;301: 26-8. 5 Robinson JO, Hibbard BM, Laurence KM. Anxiety during a crisis: emotional effects of screening for neural tube defects. J Psychosom Res 1984;28:163-9.
1973;ii:324-5. 10 Waters MFR, Philalithis PE, Lucas S. The long term prognosis of proven renal amyloidosis. Int J Lepr Other Mycobact Dis 1989;57:412.
Screening for Down's syndrome SIR,-Dr Mark Lewis and colleagues suggest that "screening [for Down's syndrome] based on individual risk would use resources more effectively than screening based on maternal age and genetic history."' As their report provides no calculations of resource use this assertion has no factual basis. Indeed, we have estimated that the type of serologically assisted screening that they describe does not offer financial savings over age related screening.2 They seem to assume that all women whose risk of bearing a baby with Down's syndrome is greater than one in 350 will wish to proceed to amniocentesis, and to termination if the result of amniocentesis is positive. This was certainly not the case in a pilot study in Brighton and Eastbourne (J Bennett, personal communication) and elsewhere. I The cost effectiveness of the programme is sensitive to the proportion of women choosing to proceed to termination. The samples studied seem irregular in two important respects. Firstly, only 52% of the total screened population had their risk of Down's syndrome estimated. It would be useful to know why 48% were not screened, the incidence of births of babies with Down's syndrome in that 48%, and any other information that would help to assess the extent of bias. Secondly, the authors have
BMJ VOLUME 303
26 OCTOBER 1991
Register for occupational skin diseases SIR,-In his editorial Dr H Keskinen reviewed occupational disease surveillance and the SWORD project (surveillance of work related and occupational respiratory diseases).' He may not be aware of parallel studies into occupational dermatoses funded by the Health and Safety Executive. A dermatological reporting scheme has been arranged through the British Contact Dermatitis Group in 16 centres in the United Kingdom. Over nine months this pilot group has identified 1116 new cases of occupational dermatitis and 60 cases of other occupational skin disorders. We have already been able to identify those occupations in which higher numbers of people have developed dermatitis and have rapidly identified factory outbreaks of both dermatitis and neoplasia as well as previously unreported dermatitic hazards. In the long term we hope to invite all dermatologists in the United Kingdom to participate. We believe that our study is particularly important because, as a result of the abolition of statutory sick pay in 1983, there is now no other source of information on the extent and causes of occupational dermatitis in the United Kingdom. Up to 1983 over half of compensated working days were lost to a condition that can cause severe and lasting disability. The excellent SWORD reporting system for occupational respiratory disorders has prepared
the ground for others to follow,' I and we expect that the benefits identified by Dr Keskinen will extend to our own surveillance. MICHAEL H BECK
Skin Hospital, Salford, Lancashire M60 9EP 1 Keskinen H. Registers for occupational diseases. BMJ7 1991;303: 597-8. (14 September.) 2 Meredith SK, Taylor VM, McDonald JC. Occupational respiratory disease in the United Kingdom 1989: a report to the British Thoracic Society and the Society of Occupational Miedicine by the SWORD project group. Br J Ind Med
1991;48:292-8. 3 Seaton A. Surveillance of work related and occupational respiratory disease-SWORD. Thorax 1991;46:548.
Hypertension and non-insulin dependent diabetes SIR,-In his appraisal of the connection between raised blood pressure and non-insulin dependent diabetes Dr John S Yudkin makes a good case for the role of insulin resistance in the development of hypertension and for the possible part played by treatment with d adrenoceptor blockers and thiazides in promoting insulin resistance. Another way of explaining the association between these two diseases is the possible though unproved effect of sulphonylurea drugs on peripheral circulation and blood pressure. Sulphonylurea drugs act like glucose on the ATP sensitive potassium channels to produce a depolarisation of the t3 cells of the pancreas, leading to release of insulin through activation of the voltage dependent calcium channels.2 Glibenclamide opposes the ATP channel activation produced by cromakalim and prevents that substance producing vasodilatation of vascular smooth muscle but in doses well above those that produce insulin release.3 The arteriolar dilating response to calcitonin gene related peptide, vasoactive intestinal polypeptide, and acetyl choline are blocked, to some extent at least, by inhibitors of ATP sensitive potassium channels.46 This raises the possibility that sulphonylurea drugs have an adverse effect on peripheral circulation and blood pressure when used to treat non-insulin dependent diabetes -a hypothesis that requires testing. RICHARD WALDEN
Department of Clinical Pharmacology, University College London and the Middlesex Hospital Medical School, London WC 1 E 6JJ 1 Yudkin JS. Hypertension and non-insulin dependent diabetes. BMJ 1991;303:730-2. (28 September.) 2 Sturgess NC, Ashford MLJ, Cook DL, Hales CN. The sulphonylurea receptor may be an ATP sensitive channel. Lancet
1985;ii:474-5. 3 Wilson C. Inhibition by sulphonylureas of vasorelaxation induced by K+ channel activators in vitro. J Auton Pharnacol 1989;9:77-8. 4 Nelson MT, Huang Y, Brayden JE, Hescheler J, Standen NB. Arterial dilatation in response to calcitonin gene related peptide involves activation of K+ channels. Nature 1990;344: 770-3. 5 Standen NB, Quale JM, Davies NW, Brayden JE, Huang Y, Nelson MT. Hyperpolarising vasodilators activate ATPsensitive K+ channels in arterial smooth muscle. Science 1989;245: 177-80. 6 Jiang C, Collins P, Poole-Wilson PA. Glibenclamide and barium inhibit endothelial dependent relaxation induced by acetylcholine in isolated rat coronary arteries. Medical Research Society Abstracts 1990;99:27.
General practitioner prescribing of erythropoietin SIR,-Professor M Orme has a somewhat negative view of general practitioner prescribing of erythropoietin. ' General practitioners are well used to sharing the care of some of their patients with specialist units. This may happen for, among others, patients with asthma, diabetes, psychosis,
1063
and colitis, and prescribing is invariably community based. Like insulin, ervthropoietin is usually administered by the patients themselves. The effects of renal failure are not limited to the patient but touch the whole family, so that the general practitioner is inevitably involved. The use oferythropoietin is conceptually simple: in renal failure a relative deficit exists, and this can now be overcome by supplementation. Erythropoietin has a good safety record, hypertension being the only common adverse effect.2 Establishing an erythropoietin programme that relies on general practitioner prescribing is no easy option. Considerable time and effort must be devoted to informing and involving general practitioners. The development of shared care protocols3 and the introduction of cooperation cards can facilitate this. Shared care provides an opportunity to increase awareness of renal medicine, which will improve everyday practice. To seek to use general practitioners simply as a prescription writing facility is clearly inappropriate.4 East Birmingham's renal unit has had three years' experience with erythropoietin and 30 months' experience with general practitioner prescribing of this drug. Apart from one case of hypertensive encephalopathy, there have been no major problems. In that case the erythropoietin was prescribed by the hospital; happily, the patient recovered fully. In our experience, with appropriate communication general practitioners are almost invariably willing to prescribe erythropoietin and share the satisfaction of bringing the benefits of this remarkable advance to their patients. Our erythropoietin programme continues to expand. Of course general practitioners are aware of the parlous financial position of renal units and resent this as much as their hospital based colleagues. Clearly, without cooperation and shared care many patients would be denied erythropoietin. What of the patients themselves? They prefer to obtain their routine medication locally and not to have to travel long distances to their hospital. S P GIBSON
10 cases would yield about £2000-that is, 10 times the marginal (or variable) cost of treating such patients. Under current rules this money would buy me only one operation through an extracontractual referral, leaving no cash for the nine other patients. The key point is that the NHS reforms cash limit patient care rather than provider activity. Up to this year, if a district ran out of cash and had to close beds the general practitioner simply sent the patient to another district for treatment. Now, once a district runs out of cash there is no money to pay for the patient to go anywhere. There is a further complication. If I reduce the smaller block contracts, generally those with the major London teaching hospitals, I create yet more difficulties. These hospitals, unless they can replace the lost work, will be forced to spread the fixed cost of their enterprise over a declining workload. The savings I may make by reducing block contracts can therefore be swallowed up by increased prices in the specialties I need, and the cases withdrawn can become unfunded. Following Dr Freeman's ill conceived advice would simply make matters worse for my population (including, incidentally, fundholding practices' patients requiring elective extracontractual referrals). I am aware that many districts are not refusing extracontractual referrals, but many are able to do this only while they have money. What Dr Freeman needs to ask is, do they have a big enough budget, and if not what happens when the cash runs out? I said in my paper that my district was atypical, and so it is. If Dr Freeman worked here he would know that too. Others may not face the same problem that I face, especially outside London. That does not invalidate my response. My list of priorities is simple: patient need, budget control, patient preference. It cannot be right to allow one patient's preferences to prevent other people from receiving any sort of care. That is the new dilemma for the NHS, and we should be discussing that much more than we are.
J B HAWKINS Renal Unit, East Birmingham Hospital, Birmingham B9 SST E S NYHOLM
Chair, East Birmingham General Practitioners' Committee, Yardley Green Health Centre, Birmingham B9 5PU
JOHN D WILLIAMSON
Richmond, Twickenham, and Roehampton Health Authority, Queen Mary's University Hospital, London SW15 5PN 1 Freeman H. Extracontractual referrals. BMJ 1991;303:788. (28 September.) 2 Williamson JD. Dealing with extracontractual referrals. BMJ
1991;303:499-504. (31 August.) 1 Orme M. How to pay for expensive drugs. BMJ 1991;303:593-4.
(14 September.) 2 Eschbach JW, Egrie JC, Downing MR, Browne JK, Adamson JW. The safety of epoetin-alpha: results of clinical trials in the United States. Contrib Nephrol 1991;88:72-80. 3 Seal R, Michael J, Gibson SP, Wilson F. Shared-care protocol epoetin. Birmingham: West Midlands Regional Health Authority, 1991. 4 Gabriel R. Picking up the tab for erythropoietin. BMJ 1991 ;302: 248-9. (2 February.)
Extracontractual referrals SIR,-Dr Howard Freeman criticises my attempt to manage extracontractual referrals by tying up too much money in contracts.' In my paper I did say that our initial planning assumptions seemed to be correct.' But lest others share Dr Freeman's confusion, at month 3 my "contracts budget" and "extracontractual referrals budget" were 106% and 102% of target. Had I not refused some requests for extracontractual referral the figures would have been 105% and 121% (because of the different sizes of those budgets). That situation has persisted to month 6. In theory, and disregarding the government's current "steady state policy," which requires all districts to place contracts on exactly the same basis, I could reduce the number of, say, wisdom tooth extractions dealt with by a block contract to find a quicker response elsewhere. A reduction of
1064
SIR,-If, as is suggested by purchasers at Merton and Sutton Health Authority,' outpatient care became free of charge to the health authority of residence the ensuing admissions and other costs would be a large expense difficult to control. A survey of 455 patient records at Watford General Hospital showed that admission to hospital was arranged at the first appointment for 24% of all new outpatients; 15% were admitted as inpatients, and 9% as day cases. Another 10% eventually had admission organised from a follow up appointment.
In addition, 30% of the new patients received some form of hospital care as an outpatient. This could be a further investigation (7%), a minor operation (16%), or physiotherapy (7%). The purchasing team at South West Hertfordshire Health Authority used these results to determine its response to elective extracontractual referrals for outpatient care. All such referrals have received consideration, as is done elsewhere. 2 I found one similar study of 1556 outpatients at Guy's Hospital in 1961,3 another of 251 medical referrals only at the Middlesex Hospital,4 and a survey at the Lister Hospital in 1986 looking at 311 acute referrals' (table). The outcomes of the first outpatient visit were similar. None of the patients in the Middlesex study were admitted. Another survey of 150 medical referrals found that 10% needed admission.6 The surgical specialties at Watford General Hospital varied, with from 9% to 70% of new outpatients having admission planned. These are the type of data Dr Williamson is looking for.2 Doubtless they will soon be available routinely as information systems improve to meet the demands of contracts. SARAH EVANS
Department of Public Health, South West Hertfordshire Health Authority, Watford WD I 8UB 1 Ghodse B, Rawaf S. Extracontractual referrals in the first three months of NHS reforms. BMJ 1991;303:497-9. (31 August.) 2 Williamson JD. Dealing with extracontractual referrals. BMJ
1991;303:499-504. 3 Blaney R, Butterfield WJH, Acheson RM, Anderson JAD, Chamberlain J, Fuller JH, et al. Outpatient study-Guy's Hospital. A study of 1556 outpatients. London: King Edward's Hospital Fund for London, 1964. 4 Department of Community Medicine, Middlesex Hospital. A study of an ouspatient clinic in a London teaching hospital. Report to King Edward's Hospital Fund. London: King Edward's Hospital Fund, 1978. 5 North West Thames Regional Health Authority. Why wait? Waiting lists and times in North West Thames. How the system works and what can be done to improve it. London: North West Thames Regional Health Authority, 1987. 6 Wilkes E. Prioritiesfor the use of resources in medicine. Washington, DC: Department of Health, Education and Welfare Publications, 1976. (Fogarty International Center Proceedings No 40.)
Environmentally friendly bottles SIR, -I find Mr B W Overton's assertion that there are benefits to the environment from use of PET (polyethylene terephthalate) bottles' both irrelevant to the topic concerned-that is, eye injuries from exploding bottles-and rather doubtful. I fail to see how a 30% incidence of recycling in the United States and an unspecified degree of reuse "in some European countries" can aid a world littered with plastic bottles. Indeed, I doubt whether the populations of India or Brazil (reported, in the article on which Mr Overton comments,2 to have high rates of eye injury from exploding glass) can be found flocking to their local recycling plant each weekend. This is a perfect example of how we are being conned on environ-
Outcomes offlrst outpatient visitfor all specialties and for medical specialties alone den ved from four surveys. Figures are percentages Watford General Hospital Guy's Hospital 1991 1%1
All Admission planned Further investigation or treatment arranged Referral to another clinic Follow up in outpatient department arranged Discharged to general practitioner with treatment arranged Discharged to general practitioner only Other
*Includes endoscopy but not cytoscopy.
Lister Hospital 1986
Medical only
All
All
18
23
5
19
33
Middlesex Hospital 1977
Medical only
Medical only
24
2
24* 2
37* 2
8
10 7
21
24
58
63
6 20 3
9 22 4
9 5 2
19 1
58t
62t
tThis figure may include some patients in other categories.
BMJ VOLUME 303
26 OCTOBER 1991
Department of Anatomy, Charing Cross and Westminster Medical School, London W6 8RF 1 Waters MFR. Use of thalidomide in leprosy. BM,J 1991;303: 470. (24 August.) 2 WHO Expert Committee on Leprosy. Sixth report. WHO Tech Rep Ser 1988;No 768. 3 Swift TR, Sabin TD. Leprous neuritis. In: Swash M, Oxbury J, eds. Clinical neurology. Edinburgh: Churchill Livingstone, 1991:1236-43. 4 Knop J, Bonsmann G, Happle R, Ludolph A, Matz DR, Mifsud EJ, et al. Thalidomide in the treatment of 60 cases of chronic discoid lupus erythematosus. Brj Dermatol 1983;108:461-6. 5 Hess CW, Hunziker T, Kupfer A, Ludlin HP. Thalidomide induced peripheral neuropathy. J Neurol 1986;223:83-9. 6 Heney D, Norfolk DR, Wheeldon J, Bailey CC, Lewis IJ, Barnard DL. Thalidomide treatment for chronic graftversus-host disease. Br7 Haematol 1991;78:23-7. 7 Crawford CL. Treatment of erythema nodosum leprosum with thalidomide. Lancet 1973;ii:567-8. 8 Crawford CL. Nature of the sensory loss in leprosy. Muscle Nerve 1988;11:276-7. 9 Levy L, Fasal P, Levan NE, Freedman RI. Treatment of erythema nodosum leprosum with thalidomide. Lancet
increased their sample size by adding a further three positive cases at the end of the study; would they have done this if the results had not supported their hypothesis? The sample size nevertheless remains inadequate. The 95% confidence interval for the detection rate extends from 39% to 94%. Such an imprecise estimate is inadequate stipport for the authors' conclusions. Finally, the authors do not take account of the psychological consequences of screening.4 We would argue that the main cost of a serological screening programme is not directly measurable in terms of money. Rather, it consists of the worry inflicted on all mothers by forcing them to consider at length the risk of their fetus suffering from Down's syndrome. Two constructive points, nevertheless, emerge. Firstly, if a pregnant woman is already sufficiently worried about the prospect of Down's syndrome to proceed to the inconvenience and risk of amniocentesis she may ethically be offered serological screening for Down's syndrome. Presumably a large proportion of pregnant women over 35 would fall into this category. Secondly, an unanswered scientific question relating to serological screening for Down's syndrome is the psychological impact on the women tested. A formal trial would help to estimate the likely psychological cost of a national screening programme.5 R M KEATINGE E S WILLIAMS
Department of Public Health Medicine, Croydon General Hospital, Croydon, Surrey CR9 2RH 1 Lewis M, Faed MJW, Howie PW. Screening for Down's syndrome based on individual risk. BMJ 1991;303:551-3. (7 September.) 2 Keatinge RM, Williams ES. Prenatal screening for Down's syndrome. BMJ7 1991;303:54-5. (6 July.) 3 Pauker SP, Pauker SG. The amniocentesis decision: ten years of decision analytic experience. March of Dimes Birth Defects Foundation, Birth Defects; Original Article Series 1987;23: 151-69. 4 Marteau T. Reducing the psychological costs. BMJ 1990;301: 26-8. 5 Robinson JO, Hibbard BM, Laurence KM. Anxiety during a crisis: emotional effects of screening for neural tube defects. J Psychosom Res 1984;28:163-9.
1973;ii:324-5. 10 Waters MFR, Philalithis PE, Lucas S. The long term prognosis of proven renal amyloidosis. Int J Lepr Other Mycobact Dis 1989;57:412.
Screening for Down's syndrome SIR,-Dr Mark Lewis and colleagues suggest that "screening [for Down's syndrome] based on individual risk would use resources more effectively than screening based on maternal age and genetic history."' As their report provides no calculations of resource use this assertion has no factual basis. Indeed, we have estimated that the type of serologically assisted screening that they describe does not offer financial savings over age related screening.2 They seem to assume that all women whose risk of bearing a baby with Down's syndrome is greater than one in 350 will wish to proceed to amniocentesis, and to termination if the result of amniocentesis is positive. This was certainly not the case in a pilot study in Brighton and Eastbourne (J Bennett, personal communication) and elsewhere. I The cost effectiveness of the programme is sensitive to the proportion of women choosing to proceed to termination. The samples studied seem irregular in two important respects. Firstly, only 52% of the total screened population had their risk of Down's syndrome estimated. It would be useful to know why 48% were not screened, the incidence of births of babies with Down's syndrome in that 48%, and any other information that would help to assess the extent of bias. Secondly, the authors have
BMJ VOLUME 303
26 OCTOBER 1991
Register for occupational skin diseases SIR,-In his editorial Dr H Keskinen reviewed occupational disease surveillance and the SWORD project (surveillance of work related and occupational respiratory diseases).' He may not be aware of parallel studies into occupational dermatoses funded by the Health and Safety Executive. A dermatological reporting scheme has been arranged through the British Contact Dermatitis Group in 16 centres in the United Kingdom. Over nine months this pilot group has identified 1116 new cases of occupational dermatitis and 60 cases of other occupational skin disorders. We have already been able to identify those occupations in which higher numbers of people have developed dermatitis and have rapidly identified factory outbreaks of both dermatitis and neoplasia as well as previously unreported dermatitic hazards. In the long term we hope to invite all dermatologists in the United Kingdom to participate. We believe that our study is particularly important because, as a result of the abolition of statutory sick pay in 1983, there is now no other source of information on the extent and causes of occupational dermatitis in the United Kingdom. Up to 1983 over half of compensated working days were lost to a condition that can cause severe and lasting disability. The excellent SWORD reporting system for occupational respiratory disorders has prepared
the ground for others to follow,' I and we expect that the benefits identified by Dr Keskinen will extend to our own surveillance. MICHAEL H BECK
Skin Hospital, Salford, Lancashire M60 9EP 1 Keskinen H. Registers for occupational diseases. BMJ7 1991;303: 597-8. (14 September.) 2 Meredith SK, Taylor VM, McDonald JC. Occupational respiratory disease in the United Kingdom 1989: a report to the British Thoracic Society and the Society of Occupational Miedicine by the SWORD project group. Br J Ind Med
1991;48:292-8. 3 Seaton A. Surveillance of work related and occupational respiratory disease-SWORD. Thorax 1991;46:548.
Hypertension and non-insulin dependent diabetes SIR,-In his appraisal of the connection between raised blood pressure and non-insulin dependent diabetes Dr John S Yudkin makes a good case for the role of insulin resistance in the development of hypertension and for the possible part played by treatment with d adrenoceptor blockers and thiazides in promoting insulin resistance. Another way of explaining the association between these two diseases is the possible though unproved effect of sulphonylurea drugs on peripheral circulation and blood pressure. Sulphonylurea drugs act like glucose on the ATP sensitive potassium channels to produce a depolarisation of the t3 cells of the pancreas, leading to release of insulin through activation of the voltage dependent calcium channels.2 Glibenclamide opposes the ATP channel activation produced by cromakalim and prevents that substance producing vasodilatation of vascular smooth muscle but in doses well above those that produce insulin release.3 The arteriolar dilating response to calcitonin gene related peptide, vasoactive intestinal polypeptide, and acetyl choline are blocked, to some extent at least, by inhibitors of ATP sensitive potassium channels.46 This raises the possibility that sulphonylurea drugs have an adverse effect on peripheral circulation and blood pressure when used to treat non-insulin dependent diabetes -a hypothesis that requires testing. RICHARD WALDEN
Department of Clinical Pharmacology, University College London and the Middlesex Hospital Medical School, London WC 1 E 6JJ 1 Yudkin JS. Hypertension and non-insulin dependent diabetes. BMJ 1991;303:730-2. (28 September.) 2 Sturgess NC, Ashford MLJ, Cook DL, Hales CN. The sulphonylurea receptor may be an ATP sensitive channel. Lancet
1985;ii:474-5. 3 Wilson C. Inhibition by sulphonylureas of vasorelaxation induced by K+ channel activators in vitro. J Auton Pharnacol 1989;9:77-8. 4 Nelson MT, Huang Y, Brayden JE, Hescheler J, Standen NB. Arterial dilatation in response to calcitonin gene related peptide involves activation of K+ channels. Nature 1990;344: 770-3. 5 Standen NB, Quale JM, Davies NW, Brayden JE, Huang Y, Nelson MT. Hyperpolarising vasodilators activate ATPsensitive K+ channels in arterial smooth muscle. Science 1989;245: 177-80. 6 Jiang C, Collins P, Poole-Wilson PA. Glibenclamide and barium inhibit endothelial dependent relaxation induced by acetylcholine in isolated rat coronary arteries. Medical Research Society Abstracts 1990;99:27.
General practitioner prescribing of erythropoietin SIR,-Professor M Orme has a somewhat negative view of general practitioner prescribing of erythropoietin. ' General practitioners are well used to sharing the care of some of their patients with specialist units. This may happen for, among others, patients with asthma, diabetes, psychosis,
1063
and colitis, and prescribing is invariably community based. Like insulin, ervthropoietin is usually administered by the patients themselves. The effects of renal failure are not limited to the patient but touch the whole family, so that the general practitioner is inevitably involved. The use oferythropoietin is conceptually simple: in renal failure a relative deficit exists, and this can now be overcome by supplementation. Erythropoietin has a good safety record, hypertension being the only common adverse effect.2 Establishing an erythropoietin programme that relies on general practitioner prescribing is no easy option. Considerable time and effort must be devoted to informing and involving general practitioners. The development of shared care protocols3 and the introduction of cooperation cards can facilitate this. Shared care provides an opportunity to increase awareness of renal medicine, which will improve everyday practice. To seek to use general practitioners simply as a prescription writing facility is clearly inappropriate.4 East Birmingham's renal unit has had three years' experience with erythropoietin and 30 months' experience with general practitioner prescribing of this drug. Apart from one case of hypertensive encephalopathy, there have been no major problems. In that case the erythropoietin was prescribed by the hospital; happily, the patient recovered fully. In our experience, with appropriate communication general practitioners are almost invariably willing to prescribe erythropoietin and share the satisfaction of bringing the benefits of this remarkable advance to their patients. Our erythropoietin programme continues to expand. Of course general practitioners are aware of the parlous financial position of renal units and resent this as much as their hospital based colleagues. Clearly, without cooperation and shared care many patients would be denied erythropoietin. What of the patients themselves? They prefer to obtain their routine medication locally and not to have to travel long distances to their hospital. S P GIBSON
10 cases would yield about £2000-that is, 10 times the marginal (or variable) cost of treating such patients. Under current rules this money would buy me only one operation through an extracontractual referral, leaving no cash for the nine other patients. The key point is that the NHS reforms cash limit patient care rather than provider activity. Up to this year, if a district ran out of cash and had to close beds the general practitioner simply sent the patient to another district for treatment. Now, once a district runs out of cash there is no money to pay for the patient to go anywhere. There is a further complication. If I reduce the smaller block contracts, generally those with the major London teaching hospitals, I create yet more difficulties. These hospitals, unless they can replace the lost work, will be forced to spread the fixed cost of their enterprise over a declining workload. The savings I may make by reducing block contracts can therefore be swallowed up by increased prices in the specialties I need, and the cases withdrawn can become unfunded. Following Dr Freeman's ill conceived advice would simply make matters worse for my population (including, incidentally, fundholding practices' patients requiring elective extracontractual referrals). I am aware that many districts are not refusing extracontractual referrals, but many are able to do this only while they have money. What Dr Freeman needs to ask is, do they have a big enough budget, and if not what happens when the cash runs out? I said in my paper that my district was atypical, and so it is. If Dr Freeman worked here he would know that too. Others may not face the same problem that I face, especially outside London. That does not invalidate my response. My list of priorities is simple: patient need, budget control, patient preference. It cannot be right to allow one patient's preferences to prevent other people from receiving any sort of care. That is the new dilemma for the NHS, and we should be discussing that much more than we are.
J B HAWKINS Renal Unit, East Birmingham Hospital, Birmingham B9 SST E S NYHOLM
Chair, East Birmingham General Practitioners' Committee, Yardley Green Health Centre, Birmingham B9 5PU
JOHN D WILLIAMSON
Richmond, Twickenham, and Roehampton Health Authority, Queen Mary's University Hospital, London SW15 5PN 1 Freeman H. Extracontractual referrals. BMJ 1991;303:788. (28 September.) 2 Williamson JD. Dealing with extracontractual referrals. BMJ
1991;303:499-504. (31 August.) 1 Orme M. How to pay for expensive drugs. BMJ 1991;303:593-4.
(14 September.) 2 Eschbach JW, Egrie JC, Downing MR, Browne JK, Adamson JW. The safety of epoetin-alpha: results of clinical trials in the United States. Contrib Nephrol 1991;88:72-80. 3 Seal R, Michael J, Gibson SP, Wilson F. Shared-care protocol epoetin. Birmingham: West Midlands Regional Health Authority, 1991. 4 Gabriel R. Picking up the tab for erythropoietin. BMJ 1991 ;302: 248-9. (2 February.)
Extracontractual referrals SIR,-Dr Howard Freeman criticises my attempt to manage extracontractual referrals by tying up too much money in contracts.' In my paper I did say that our initial planning assumptions seemed to be correct.' But lest others share Dr Freeman's confusion, at month 3 my "contracts budget" and "extracontractual referrals budget" were 106% and 102% of target. Had I not refused some requests for extracontractual referral the figures would have been 105% and 121% (because of the different sizes of those budgets). That situation has persisted to month 6. In theory, and disregarding the government's current "steady state policy," which requires all districts to place contracts on exactly the same basis, I could reduce the number of, say, wisdom tooth extractions dealt with by a block contract to find a quicker response elsewhere. A reduction of
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SIR,-If, as is suggested by purchasers at Merton and Sutton Health Authority,' outpatient care became free of charge to the health authority of residence the ensuing admissions and other costs would be a large expense difficult to control. A survey of 455 patient records at Watford General Hospital showed that admission to hospital was arranged at the first appointment for 24% of all new outpatients; 15% were admitted as inpatients, and 9% as day cases. Another 10% eventually had admission organised from a follow up appointment.
In addition, 30% of the new patients received some form of hospital care as an outpatient. This could be a further investigation (7%), a minor operation (16%), or physiotherapy (7%). The purchasing team at South West Hertfordshire Health Authority used these results to determine its response to elective extracontractual referrals for outpatient care. All such referrals have received consideration, as is done elsewhere. 2 I found one similar study of 1556 outpatients at Guy's Hospital in 1961,3 another of 251 medical referrals only at the Middlesex Hospital,4 and a survey at the Lister Hospital in 1986 looking at 311 acute referrals' (table). The outcomes of the first outpatient visit were similar. None of the patients in the Middlesex study were admitted. Another survey of 150 medical referrals found that 10% needed admission.6 The surgical specialties at Watford General Hospital varied, with from 9% to 70% of new outpatients having admission planned. These are the type of data Dr Williamson is looking for.2 Doubtless they will soon be available routinely as information systems improve to meet the demands of contracts. SARAH EVANS
Department of Public Health, South West Hertfordshire Health Authority, Watford WD I 8UB 1 Ghodse B, Rawaf S. Extracontractual referrals in the first three months of NHS reforms. BMJ 1991;303:497-9. (31 August.) 2 Williamson JD. Dealing with extracontractual referrals. BMJ
1991;303:499-504. 3 Blaney R, Butterfield WJH, Acheson RM, Anderson JAD, Chamberlain J, Fuller JH, et al. Outpatient study-Guy's Hospital. A study of 1556 outpatients. London: King Edward's Hospital Fund for London, 1964. 4 Department of Community Medicine, Middlesex Hospital. A study of an ouspatient clinic in a London teaching hospital. Report to King Edward's Hospital Fund. London: King Edward's Hospital Fund, 1978. 5 North West Thames Regional Health Authority. Why wait? Waiting lists and times in North West Thames. How the system works and what can be done to improve it. London: North West Thames Regional Health Authority, 1987. 6 Wilkes E. Prioritiesfor the use of resources in medicine. Washington, DC: Department of Health, Education and Welfare Publications, 1976. (Fogarty International Center Proceedings No 40.)
Environmentally friendly bottles SIR, -I find Mr B W Overton's assertion that there are benefits to the environment from use of PET (polyethylene terephthalate) bottles' both irrelevant to the topic concerned-that is, eye injuries from exploding bottles-and rather doubtful. I fail to see how a 30% incidence of recycling in the United States and an unspecified degree of reuse "in some European countries" can aid a world littered with plastic bottles. Indeed, I doubt whether the populations of India or Brazil (reported, in the article on which Mr Overton comments,2 to have high rates of eye injury from exploding glass) can be found flocking to their local recycling plant each weekend. This is a perfect example of how we are being conned on environ-
Outcomes offlrst outpatient visitfor all specialties and for medical specialties alone den ved from four surveys. Figures are percentages Watford General Hospital Guy's Hospital 1991 1%1
All Admission planned Further investigation or treatment arranged Referral to another clinic Follow up in outpatient department arranged Discharged to general practitioner with treatment arranged Discharged to general practitioner only Other
*Includes endoscopy but not cytoscopy.
Lister Hospital 1986
Medical only
All
All
18
23
5
19
33
Middlesex Hospital 1977
Medical only
Medical only
24
2
24* 2
37* 2
8
10 7
21
24
58
63
6 20 3
9 22 4
9 5 2
19 1
58t
62t
tThis figure may include some patients in other categories.
BMJ VOLUME 303
26 OCTOBER 1991
