Biomedical subjects
Publications and source records attributed to F Gremy.
This paper claims that, when evaluation of information systems is at stake, it is impossible in most cases to discard human subjectivity in the same way that one cannot discard quality of life when a therapeutic strategy is to be evaluated.
In order to analyse the various factors which determine physician's position on the use of opiates in a substitution treatment--as a harm-reducting and heroin dependence treatment tool-, 97 French physicians (i.e. 47 general practioners, 36 psychiatrists, 10 internists, 4 emergency care practioners) answered anonymously 103 closed questions, in presence of a single investigator. Among these 97 physicians, 40 were choosed at random from a list of addiction treatment's practioners, 19 were choosed nominatively for their explicit point of view toward substitution, and 38 were choosed at random from the Herault physicians register. In this latter sample, the survey showed a majority of physicians took an ambivalent position towards substitution, or were favourable without being prescriptors themselves--even though meeting drug users-. General practioners were more favourable to drug substitutes than specialists (50% vs 22%). This practice appeared as legitimate for 70% of physicians; AIDS helped justify this attitude for 26% of the specialists and 5% of the general practioners. Individual or socio-professional factors, the representations of the drug-addict and of his suffering, the perceptions of AIDS contamination risk and the standards of knowledge on the substitution treatments did not differ significatively (p < 0.02) between the groups, determinated according to the expressed practioners point of view toward substitution. Using a method exploring opinion structuration, no description of the typical doctor can be drawn from his position towards substitution. Militant discourses were rare; the main disagreements concerned the status, the negotiation around "the product ... or the medicament" within the drug addict-physician relationship should have. Substitution was considered by some as a mere shift from one object of dependence to another; and to others, as a means of setting up a therapeutic relationship. Ambivalent opinions frequently noticed in the physician's point of view towards substitution appears as a multifactorial phenomenon. Not only does it reveal the physician's difficultie in adapting previous patterns of treatment which are not longer adequate to a critical situation, but it also questions the foundations of the very relationship between the practioner and the drug addict.
A retrospective study was planned in the Hérault (Mediterranean) region of France where bladder cancer mortality and incidence rates are high. In the present paper, variations in bladder cancer risk according to various smoking-related variables, in particular time of exposure and type of tobacco, are examined. This case-control study with 219 male incident cases and 794 male population controls randomized from electoral rolls was carried out in 1987-89. Trained interviewers obtained information on demographics, dietary habits (coffee, alcohol, artificial sweeteners, vegetables, spices, etc.), occupational exposures and detailed history of tobacco smoking (average number of cigarettes per day, number of years of smoking, age at which they began and/or quitted smoking, use of filter-tip and type of tobacco). The odds ratio (OR) for cigarette smokers versus non-smokers was greater than 5. Results for number of cigarettes daily, duration of smoking and lifetime smoking showed a highly significant dose-response relationship, which was confirmed when these variables were treated as continuous in a logistic regression model. Eighty-eight percent of the smokers used black tobacco. Quitting smoking did not result in a significant reduction in bladder cancer risk. Higher risks were associated with starting to smoke at an early age (OR before age 13 versus after age 21 = 3.42; 95% CI 1.07-10.9) and with black tobacco smoking (OR black versus blond = 1.63; 95% CI 0.73-3.64). Results suggest that black tobacco may be more harmful than blond tobacco and may have an early non-reversible role in bladder carcinogenesis.
In the Hérault region of France, vineyards cover an area of 128,000 hectares (60% of agricultural land) and involve more than 93% of farms. A vine-growing exposure matrix was built for assessing pesticide exposure. It is based on information obtained from a survey among 85 vine-growers who lived in Hérault and who had detailed account books. This paper explains how this matrix was built and how to use it. It takes into consideration the calendar time (1950-1988), the type of products (powder, liquid) and the chemical classes. It can estimate the likelihood of exposure and the quantity of pesticide used. Such a matrix could be useful in epidemiological surveys in order to measure vine-growers' exposure to pesticides. Formulae are given to evaluate their mean exposure to these chemicals. Limitations of the matrix are discussed; it does not take into account several factors which might change exposure: temperature, wind speed, methods of application, use of protection, etc.
Lactitol (beta-galactosido-sorbitol) has been recently compared with lactulose for the treatment of chronic hepatic encephalopathy in a few studies, each comprising a small number of patients. The results are controversial. We studied the efficiency and tolerance of both compounds by using a meta-analysis on the basis of published controlled trials. Our study only included controlled or randomized trials comprising cirrhotic patients with chronic hepatic encephalopathy. Analyzed parameters were the portosystemic encephalopathy index of Conn after treatment, the percentage of improved patients and the percentage of patients who had ill effects related to the treatment (flatulence, diarrhea). Bibliographical screening revealed five studies comparing the effects of lactitol and lactulose in chronic hepatic encephalopathy. Four crossover studies were done that included 48 patients and one parallel study that included 29 patients. The duration of the treatment ranged from 3 to 6 mo. All studies found a similar efficiency with both drugs. However, they exhibited some discrepancies in the relative frequency of adverse reactions (flatulence). Meta-analysis showed no statistical differences in the portosystemic encephalopathy index after lactitol or lactulose treatment. The percentage of improved patients after lactitol or lactulose was similar. In contrast, the analysis revealed a higher frequency (p less than 0.01) of flatulence in patients treated with lactulose compared with those treated with lactitol. In conclusion, this meta-analysis shows no statistical difference between therapeutic effects of lactitol and lactulose, but it does show a higher frequency of flatulence with lactulose. This suggests that lactitol should be preferred to lactulose for the treatment of chronic hepatic encephalopathy.
A meta-analysis of 10 randomized trials comparing steroid therapy with placebo or abstention was performed. Trials were pooled for severity of acute alcoholic hepatitis and time of analysis. Papers with survival analyses at one and three months were included. The robustness of this meta-analysis was analysed after exclusion of trials analysing survival at three months only, trials including mild forms, or atypical trials. Comparisons were made use the Der Simonian-Laird and Mantel-Haenszel-Peto methods. All results were statistically significant. However, if only one medium size trial were to be added, the results would no longer be significant. Taking into account the complications of steroid therapy, we conclude that further clinical trials are necessary to confirm the effectiveness of steroid therapy, especially for the group of patients with severe alcoholic hepatitis.
A case-control investigation about bladder cancer was carried out in Herault department with 219 incident cases from January 1987 to May 1989 and two control groups: 196 hospital controls randomized from hospital admission lists and 794 population controls randomized from census data. According to the comparison for those two groups, there are few socio-demographic differences; but hospital controls are more exposed to smoking, coffee, alcohol, artificial sweetners. So, the odds ratios with those hospital controls are under-estimated. We can evaluate the resulting biais.
The main reason for using low molecular weight heparin (LMWH) is its capacity to keep the antithrombotic effect of standard non-fractioned heparin (NFH) while reducing its hemorrhagic power. Various studies comparing LMWH to NFH gave contradictory results, so we carried out a meta-analysis of randomized trials comparing these two treatments in prevention of deep-vein thrombosis (DVT) (and in prevention of deep-vein thrombosis or pulmonary embolism). From a selection of ten trials we could not show any significant difference in the DVT rates, as well as for the whole of surgical indications as for the subgroups of abdominal and orthopedic surgery. The weighted global difference between the DVT rates is so low that, in spite of the use of meta-analysis, the power is clearly insufficient. The hemorrhagic risk is not statistically reduced as well for the whole of surgical indications as for the subgroups.
Survival is an objective criteria, reliable, easy to measure and easy to analyse. But this criteria, the most important in almost all therapeutic trials, is a very rough one and not all fitted to many questions raised in cancer treatment decision making. We suggest a new criteria, combining quality and quantity of survival, which is equivalent in years of survival at a maximal quality level to the time of survival at a varying level of a cancer patient. This criteria could be usefull in the majority of "palliative" clinical trials (advanced cancers, recurrences, metastatic evolution...).
It is a truism that medicine is in a crisis but the truism is right. This paper sets out the symptoms of the crisis. The effectiveness of modern medicine has been questioned by many. Doctors use too many tests and do not always understand the results. This is the practice of 'decerebrate medicine'. The alleged triumphs of modern medicine have made only a modest impact on mortality rates and death from iatrogenic causes is real. Modern medicine is allied to the industrial society with its hierarchies and division of work. This leads to tensions between doctors and between doctors and their patients. Administrators fear the progressive rise in health costs and ask whether more really means better. Economists demand evaluation of medical procedures and there is a growing demand for real preventive medicine. Health is a problem for the whole of society. This paper then sets out the epistemological aspects of the crisis in medicine. It suggests that a new paradigm must be constructed in the light of the scientific revolution. The concept of medicine based on analytical science with its reductionism and disjunctivism is not enough to cover the complexity of man. The new paradigm needs to embrace all the sciences, both of nature and of man. A view is given of how this process of comprehending an exceedingly complex problem should be tackled and the role to be played by information sciences.
The authors have designed a multicriteria framework for the analysis of health indexes in order to provide a tool for the comparison of population health status indexes and to establish a typology of these indexes regarding their use for public health. This framework allows for (a) shedding some light on the conceptualization of health underlying each index, (b) understanding the nature of the phenomenon which are effectively measured, (c) understanding the principles of the construction of the index, (d) giving some details concerning its main properties, (e) and finally understanding its possible uses. Using this multicriteria framework for analyzing and comparing 16 different population health status indexes, the authors suggest some guidelines for choosing an index regarding its future utilization (identification of priorities, resources allocation, evaluation). Finally, the limits of the utilization of health status indexes within the process of decision making in public health are underlined.
Survivals of two series of CLL patients (99 from a retrospective series and 196 from a prospective series) were studied separately. The three main staging systems (Rai, Binet, Rundles) agreed well, but as far as survival is concerned, too many stages are defined. The authors performed a Cox multivariate analysis of survival in order to isolate important prognostic factors at diagnosis and to use them to build a simple three-stage classification. Thrombopenia and anemia appeared as the most important risk factors. Among the nonanemic and nonthrombopenic patients, the number of involved areas was clearly related to prognosis in the authors' two series. This study allowed the authors to propose a new classification in three prognostic groups. Group C: anemia (Hb less than 10 g) and/or thrombopenia (platelets less than 100,000/mm3); about 15% of the patients; median of 2 years. Group B: no anemia, no thrombopenia, three or more involved areas (counting as one each of the following: axillary, cervical, inguinal, lymph nodes, whether unilateral or bilateral, spleen and liver); about 30% of patients; median of 7 years. Group A: no anemia, no thrombopenia, less than three involved areas; about 55% of patients; the survival of this group does not seem different from that of the French population of the same age and sex distribution. This three-stage classification only requires clinical examination and routine hemogram, has a good prognostic value which was confirmed on the series of Montserrat and Rozman (146 patients), and should therefore be helpful in planning new clinical trials.
The rapid discovery of new markers systems makes it impossible for financial reasons to study the polymorphism determination of all known genetic markers when dealing with parenthood problems. We propose to use the percentage of rejected subjects with respect to the (mother, children) set as a decision tool to define a sequence which provides the maximum information for the minimum cost. This decision rule is evaluated with a sample of 150 families whose polymorphism is determined on the same sequence of 20 genetic markers.
Mortality statistics are underutilized in France. Authors show that it is possible to use them for small population (125 000). Classical statistical methods are utilized. The interpretation of the results is difficult with regard to the quality of National data. Comparison data conclude that mortality rates are lower within the industry for lung and gastrointestinal disease, suicide, injuries and that three health problems are more prevalent: alcholism, injuries for young men and cancer.
The knowledge of human polymorphism provides an invaluable tool in the analysis of parenthood. This paper deals with the fatherhood diagnosis within a family (presumed father, mother, children) and describes a computer program, called Fratrie, which identifies parenthood rejections and computes different decisional indices. The analysis of these indices points out a neglected index, the percentage of men rejected with respect to the (mother, children) set. We propose a new decisional strategy using this index.
The value of prognostic information and some of the statistical aspects of prognostic studies are discussed. In the first part, seven areas of medical activity where knowledge of prognostic factors is used are identified: prediction of disease evolution, treatment decisions, design and analysis of clinical trials, comparison of non-randomized series of patients, assessment of additional clinical examinations and laboratory tests, understanding of the physio-pathology of disease, screening. In the second part, the nature of the data collected in prognostic studies is discussed, and a few statistical methods useful for the identification of prognostic factors are outlined. The paper concludes with an example of a prognostic study in Chronic Lymphocytic Leukemia.
Two problems are envisaged: --the relationship between the "statistical decision" and the individual decision. Long before the existence of decision-making aids, medical knowledge has always been of a statistical nature. Ever since medicine became an organised science, the treating of a patient and not just the illness has been a constant problem. At present, it is by no means certain that we have the right to apply the strategy recommended by a well organised therapeutic trial, with our eyes shut. If for no other reason, simply because the criteria of judgment of the trial may not necessarily be the criterion best adapted to the patient concerned. --how to implicate in decision and evaluation non-quantitative criteria such as the quality of survival. Having recalled the distinction made by Wood--impairment, disability, handicap--an attempt is made to specify the state of sanometric research providing physicians with health indexes that are finer than the simple Boolean criteria of Life/Death. In conclusion, the question can be raised as to how pertinent, it is to consider death as the lowest level of health, and as to what role should be left to the patient in the choice of decision-making criteria for problems directly concerning his own fate.
A quantitative analysis of the diagnostic contribution of the classical special investigation normally used in hospital neurology. Six examinations were studied: laboratory blood investigations, electroencephalogramm, lumbar puncture, optic fundus, standard skull X-ray, standard spine X-ray. The analysis involved 548 patients in whom 2219 examinations were performed with a yield of 26 "corrected" diagnosis (a diagnosis in which there was a clinical error corrected in the light of the results of these examinations).