MEASURING NEED FOR HEALTH CARE

29

evening doses and produce minimum suppression of day-time gastric acid,11-12 which has the theoretical advantage of maintaining a bactericidal intragastric milieu during the day. A similar result can be achieved with single nocturnal doses of cimetidine or ranitidine. Perhaps the relapse rate on withdrawal will be less with the new compounds than with the original Hz antagonists,13 although it is unlikely that any Hz antagonist will influence Campylobacter pylori, which appears to be implicated in duodenal ulcer recurrence.14 Are famotidine and nizatidine likely to be safer than their predecessors? Cimetidine and ranitidine are among the safest of all effective agents in the therapeutic armamentarium. Prescribing them as a single dose at night will probably reduce the incidence of toxicity even further. Side-effects of nizatidine and famotidine have already been reported: those listed on the data sheets include dry mouth,

anorexia, nausea, vomiting, constipation, diarrhoea, headache, dizziness, fatigue, and rashes with famotidine and asthenia, chest pain, headache, myalgia, vivid dreams,

rhinitis, pharyngitis, cough, sweating,

and pruritus with of nizatidine. None these reactions is common but neither are any of the side-effects of cimetidine or ranitidine. It is too early to say whether the new drugs will produce serious idiosyncratic reactions. Famotidinels and nizatidine16 do not bind appreciably to cytochrome P450 and so do not inhibit oxidative drug metabolism. Are there any clear advantages with these newer agents?-they do not hold out the prospect of cheaper anti-ulcer therapy. They undoubtedly provide much needed research revenue for impoverished investigative units, especially as their effectiveness is predictable and the potential market is so vast. There is also welcome advertising profit for medical journals and periodicals, some of which contain a "full house" of 7 pages on famotidine (based largely on a quarter-page abstract17), 4 on nizatidine, 2 on ranitidine, and 1 on cimetidine! In the UK, the Committee on Safety of Medicines (CSM) requires appropriate data on efficacy and safety if a novel therapeutic agent is to be granted a product licence. Surely greater consideration should be given to the question of clinical need for the new drug, which is often more costly than tried and tested treatments for the same indication. Whilst it is difficult to say with certainty that a new chemical entity will not turn out to have some sort of therapeutic advantage (or toxic effect) not possessed by its competitors,, avenues for expanding the clinical potential of a drug are more hopeful if there are novel aspects to its pharmacology. Hz antagonists all block the same group of receptors, they act 9. Simon B, Cremer M, Dammann HG, et al 300 mg nizatidine at night versus 300 mg ranitidine at night in patients with duodenal ulcer. Scand J Gastroenterol 1987; 22 (suppl 136) 61-70 10. Naccaratto R, Cremer M, Dammann HG, et al. Nizatidine versus ranitidine in gastric ulcer disease. Scand J Gastroenterol 1987, 22 (suppl 136): 71-78. 11. Chremos AN. Pharmacodynamics of famotidine in humans Am J Med 1986; (suppl 4B) 3-7. 12 Callaghan JT, Bergstrom RF, Obermeyer BD, King EP, Offen WW Intravenous nizatidine kinetics and acid suppression. Clin Pharmacol Ther 1985; 37: 162-65 13. Miller JP, Faragher GB. Relapse of duodenal ulcer does it matter which drug is used in initial treatment? Br Med J 1986, 293: 1117-18 14 Coghlan JG, Gilligan D, Humphries H, McKenna D, Dooley C, Sweeney E, Keane C, O’Morain C Campylobacterpylori and recurrence of duodenal ulcers-a 12-month follow-up study. Lancet 1987; ii: 1109-11. 15 Lin JH, Chremos AN, Chlou R, Yeh KC, Williams R. Comparative effect of famotidine and cimetidine on the pharmacokinerics of theophylline in normal volunteers Br J Clin Pharmacol 1987, 24: 669-72. 16 Secor JW, Speeg KV, Meredith CG, Johnson RF, Snowdy P, Schenker S Lack of effect of nizatidine on hepatic drug metabolism in man Br J Clin Pharmacol 1985, 20: 710-13 17. Bauerfeind P, Cilluffo T, Emde C, et al H2-antagonists are more effective after early evening intake than after late intake Gastroenterology 1986; 90: 1340 (abstr).

primarily as very efficient antacids and, as such, may not greatly affect the long-term outcome of peptic ulcer disease. They differ in potency and, to a lesser extent, in elimination half-life, which may marginally influence efficacy. How many more Hz antagonists do we need? At present, the Medicines Act (1968) does not place a ceiling on the number of "me-too" drugs. Common sense (and increasing drug costs) suggest that this nettle will have to be grasped sooner or

later.

MEASURING NEED FOR HEALTH CARE NEARLY forty years ago, soon after the formation of the National Health Service, it became widely recognised that demands for health care could not be met. Resources would have to be rationed according to need. Since then, health services epidemiology, health economics, medical statistics, and operational research have mushroomed; there have been substantial improvements in national databases describing the health and welfare of the population. However, despite these changes, planners are still floundering with the measurement of need for health care, particularly for the purposes of resource allocation between

regions. A major difficulty

in the assessment of need is that measurement has relied on routine databases that were not designed primarily for that purpose. The Resource Allocation Working Party (RAWP) recommended standardised mortality ratios (SMRs) as proxy measures for morbidity in addition to that attributed to a population’s age and sex structured The use of SMRs by RAWP has been criticised because of doubts about the relation between mortality and morbidity. Deprived populations are thought to have a much higher level of morbidity relative to their SMRs than those which are more affluent, and to have a greater need for inpatient care because of poor housing conditions and domestic circumstances. Various social indicators, such as socioeconomic groups and classifications of residential neighbourhoods, have been proposed as better measures of need, but they offer little advantage over SMRS2 and conceptually are even further removed from a measurement of disease. In 1986 a steering group set up by the NHS Management Board to review the RAWP formula recommended more research into the validity of using SMRs and other indicators as proxy measures of

community morbidity.3 Statistics on the use of hospitals have for many years been dismissed as totally inadequate indicators of need but, given the continuing frustration with the use of SMRs, a reappraisal of this issue by Morgan and colleagues4 is welcome. These workers begin on a sceptical note by suggesting that large variations in hospital use, for example 25% differences in admission rates between Trent and Yorkshires and two-fold variations in surgical rates within Englandare unlikely to be explained simply by regional 1. Department of Health and Social

Security. Sharing resources for health m England. Report of the Resource Allocation Working Party London: HM Stationery Office,

1976 2. Mays N. Measuring

morbidity for resource allocation. Br Med J 1987; 295: 703-06. 3. Department of Health and Social Security. Review of the Resource Allocation Working Party formula. London DHSS, 1986. 4. Morgan M, Mays N, Holland WW Can hospital use be a measure of need for health care.J Epidemiol Comm Health 1987; 41: 269-74. 5. London Health Planning Consortium Acute hospital services in London- a profile by the London Health Planning Consortium London: HM Stationery Office, 1979. 6. McPherson K, Strong PM, Epstein A, Jones L. Regional variations in the use of common surgical procedures within and between England and Wales, Canada and the United States of America Soc Sci Med 1981, 15A: 273-88.

30

Equally important is the supply of notably hospital beds and manpower, affecting clinical decisions. Thus most general practitioners are acutely aware that their referral decisions are affected by the length and duration of waiting lists. Similarly, in hospitals, decisions to admit and discharge patients are affected by bed availability.7,8 Wennberg et al lately reported that Boston, which has nearly twice as many hospital beds and staff per caput as New Haven, has a 34% higher admitting rate.8 Moreover, the use of acute hospital services may be affected by the provision of beds in the private sector and by alternative care in convalescent nursing homes. Variations in professional practice may be an independent differences in morbidity. resources,

factor

affecting hospital use. General practitioner referral considerably within the same practice and for patients with similar problems.9 Indeed, Dowie1O found that much of the variation in referral rates could be explained by the professional attributes of general practitioners, such as their medical knowledge and consulting styles. In hospital practice, decisions to admit and discharge patients are often based on medical opinions for which there is no general consensus. Under what circumstances, for example, should patients with pneumonia be admitted to hospital, and at what point in the course of their illness should they be sent home? It has been estimated that the need for hospital admission is not clearly defined for more than 80% of rates vary

medical conditions." Thus major difficulties arise in assigning broadly based statistics on hospital use as indicators of need. Morgan et al4 quite rightly conclude that such statistics cannot be used as a basis for resource allocation since the use of hospitals is heavily influenced by levels of provision, the organisation of services, and professional practice. It would, however, be unwise to dismiss such statistics completely out of hand, particularly since a huge and reliable data source, the Hospital Inpatient Enquiry, is available for analysis. Although use is never totally independent of supply, some specific measures may reflect levels of morbidity quite accurately. Few clinicians would doubt, for example, that admission rates for fractured neck of femur, substantial ,

upper

gastrointestinal haemorrhage,

or acute

hemiplegic

stroke in middle-age are not closely related to incidence rates in the community. In developing methods for evaluating the quality of health services, Kessner12 introduced the idea of selecting tracer medical conditions, each of which impinges upon specific parts of the service. Evaluation of the management of a series of tracers provides a comprehensive assessment of the quality of the service. In a similar way, a combination of disease-specific hospital statistics might be used to indicate the overall health needs of a community. Some form of diagnosis related groups (DRGs) might also be developed for use in this context. Alternatively, attention could be given to devising and evaluating other data sources as measures of morbidity. Questions on health might be included in the national census and more incorporated into

7.

Logan RFL, Ashley JSA, Klein RE, Robson DM. Dynamics of medical care. the Liverpool study into use of hospital resources. Memoir no 14. London. London School of Hygiene and Tropical Medicine, 1972 8. Wennberg JE, Freeman JL, Culp WJ. Are hospital services rationed m New Haven or over-utilised in Boston? Lancet 1987, i 1185-89 9 Royal College of General Practitioners Birmingham Research Unit Practice activity analysis referrals to specialists. J R Coll Gen Pract 1978; 28: 251-52. 10. Dowie R. General practitioners and consultants in a study of outpatient referrals. London: King Edward’s Hospital Fund for London, 1983. 1 1. Wennberg J. Which rate is right? N Engl J Med 1986; 314: 310-11. 12. Kessner DM, Kalk CE, Singer J. Assessing health quality-the case for tracers. N Engl J Med 1973; 288: 189-94

the General Household Survey. The frequency, content, and coverage of the morbidity surveys in general practice" might be increased. Regional health authorities might be required to carry out ad hoc surveys of community morbidity to supplement their data on the provision and use of services. Unfortunately, even valid measures of morbidity will not

provide

a

simple

answer to more

appropriate

resource

allocation because morbidity is not necessarily equated with the need for health care and often cannot be alleviated. Thus research into measures of morbidity must go hand in hand with investigation of the outcomes of medical care. Given the vast sums of money involved in resource allocation in the NHS, more investment in such research might yield substantial dividends.

PLASTIC DEVICES: NEW FIELDS FOR OLD MICROBES IT would be an exaggeration to state that advances in medicine create more problems than they solve; but problems there are, and one of these is usually infection. The increasing use of plastic devices-whether intravascular catheters, continuous ambulatory peritoneal dialysis (CAPD) lines, cerebrospinal fluid shunts, or heart valve and joint prostheses-is a case in point. Microbes are never slow to display their boundless ingenuity and these manmade surfaces, in proximity to nutrient-rich tissues, provide new territory for the ever-resourceful bacteria to colonise. A wide variety of well-known opportunist organisms, from pseudomonads to yeasts, may be responsible for such infections and, as expected, that most versatile of pathogens, Staphylococcus aureus, is often involved. However, the most frequently encountered organisms in device-related infection are not the traditional microbial felons, but ordinarily peace-loving elements of the normal skin flora, notably Staph epidermidis and its close relatives,l,2which are distinguished from the more notorious Staph aureus in the laboratory by their failure to coagulate human plasma. Why coagulase-negative staphylococci are particularly suited to colonising plastic devices is not entirely clear. They are, of course, ubiquitous as normal skin commensals, so they are handily placed to flourish at the site of insertion of cannulae, or to smuggle themselves through connections to gain internal access, but it has been assumed that other factors must predispose to the primacy of these organisms in device-related sepsis. Some strains produce a copious amount of extracellular slime and this no doubt aids the colonisation process; once established, microcolonies of bacteria, often residing in microdefects in the plastic surfacemay acquire a protective coat derived from the slime, which effectively prevents even strongly bactericidal antibiotics from sterilising the site.4 Moreover, coagulase-

13.

Royal College of General Practitioners, Office of Population Censuses and Surveys, Department of Health and Social Security. Morbidity statistics from general practice, 1981-82. London HM Stationery Office, 1986 1. Fleer A, Verhoef J. New aspects of staphylococcal infections emergence of coagulase-negative staphylococci as pathogens Antonie van Leeuwenhoek 1984; 50: 729-44.

2.

Lowy FD, Hammer SM. Staphylococcus epidermidis infections. Ann Intern Med 1983;

3.

Cheesbrough JS, Elliott TSJ, Finch RG. A morphological study of bacterial colonisation of intravenous cannulae J Med Microbiol 1985; 19: 149-57. Costerton JW, Cheng K-J, Geesey GG, et al. Bactenal biofilms in nature and disease.

99: 834-39.

4.

Ann Rev Microbiol 1987, 41: 435-64