[Personal and occupational factors associated with low-back pain in a general working population in France]. / Facteurs personnels et professionnels associés aux lombalgies en population générale au travail en France.

BACKGROUND: Low-back pain is a major public health concern because of its socioeconomic burden, especially for chronic forms. The purpose of this study was to analyse the associations between low-back pain and occupational and personal factors, with a special focus on interactions between age and occupational exposures. METHODS: The study population comprised a sample of 3958 and 4526 working women and men aged 30 to 59 derived from a national health survey (2002-2003 EDS). Low-back pain was assessed using the French version of the Nordic questionnaire. Weight, height and smoking status were obtained through interview at home. Occupational exposures were self-assessed. The associations between low-back pain for more than 30 days in the previous year and occupational and personal factors were assessed using logistic models. An interaction between age and each occupational exposure was studied. RESULTS: In the multivariate models, age was the only personal factor significantly associated with low-back pain for both genders. The other personal factors studied were significantly associated with low-back pain for women only. Handling heavy loads and awkward postures at work were strongly associated with low-back pain for both genders (respectively OR=1.80 [1.46-2.23] and OR=1.65 [1.34-2.03] for men, and OR=1.65 [1.32-2.06] and OR=1.28 [1.04-1.59] for women). A high level of psychological demands at work and a low level of decision latitude were also associated with low-back pain for both genders (respectively OR=1.22 [1.03-1.46] and OR=1.32 [1.11-1.57] for men, and OR=1.31 [1.10-1.56] and OR=1.27 [1.06-1.51] for women). Only the interaction between age and awkward postures for men was borderline significant. CONCLUSION: This study showed strong associations between occupational exposures and persistent/recurrent low-back pain in a general working population in France. Targeting these exposures in prevention programs could be useful.

Seeking care for lower back pain in the French population aged from 30 to 69: the results of the 2002-2003 Décennale Santé survey.

OBJECTIVES: To describe the frequency with which members of the French general population in the 30-to-69 age class sought care for lower back pain (LBP) from various healthcare professionals and to identify associated parameters. MATERIAL AND METHODS: Data were collected in the 2002-2003 Décennale Santé survey, which is representative of ordinary households in continental France. We assessed the frequency with which the 17,792 surveyed individuals sought care for LBP by considering consultations with healthcare professionals in general and consultations with general practitioners and physiotherapists in particular. RESULTS: Among the survey subjects, 4.5% reported that they had sought treatment for LBP from a healthcare professional at least once during the 2-month survey period. The decision to seek care was correlated with the characteristics of the LBP. The duration of the pain was associated with the frequency of all types of consultation studied here. Sociodemographic, economic and occupational risk factors were also involved. Consultation with a physiotherapist was related to income. CONCLUSION: These results from a representative sample of the French general population show that the factors associated with seeking treatment for LBP differ according to the type of healthcare professional consulted.

Prevalence of educational inequalities in obesity between 1970 and 2003 in France.

This paper examines trends in obesity rates and education-related absolute and relative inequalities in obesity over the last 40 years in France. Data are drawn from the French Decennial Health Surveys of 1970, 1980, 1991 and 2003. The difference in obesity rates between the least- and most-educated, the Slope Index of Inequality, is used to estimate absolute inequalities in obesity. The ratio of the corresponding rates, the Relative Index of Inequality, reveals the relative inequalities in obesity. Obesity rates were similar in men and women, but educational inequalities were greater in women. Obesity rates were similar over the first three surveys but increased for all in the 2003 survey. This increase was accompanied by increases in absolute inequalities in men (P = 0.04) from a Slope Index of Inequality of 4.80% (95% confidence interval [CI] = 2.27, 7.32) to 8.64% (95% CI = 5.97, 11.32) and women (P = 0.004) from 8.90% (95% CI = 6.18, 11.63) to 14.57% (95% CI = 11.83, 17.32). Relative inequalities in obesity remained stable over the 40 years. Recent increase in obesity rates in France is accompanied by increases in absolute education-related inequalities, while relative inequalities have remained stable; this suggests that obesity rates have increased at a much faster rate in the low-education groups.

Frequency of low back pain among men and women aged 30 to 64 years in France. Results of two national surveys.

INTRODUCTION: In France, most studies of low back pain (LBP) have been carried out among workers or patients. Until very recently, the frequency of LBP in the general population was not known, because National Health Surveys did not include questions on LBP. OBJECTIVE: To estimate the prevalence of LBP in the French population aged 30 to 64 years. MATERIALS AND METHODS: The main data were from the National Health Survey 2002-2003 (n=14,248). LBP was assessed by an accompanying self-administered questionnaire asking details about duration of LBP in the previous 12 months. Weights were used to estimate the prevalence of LBP in the French population, with two definitions of LBP. Additional results dealing with chronic LBP, from another national survey (Handicap, Disability and Dependence), are also briefly presented. RESULTS: More than half of the French population in this age group experienced LBP at least one day in the previous 12 months (LBP1), with 17% experiencing LBP for more than 30 days in the previous 12 months (LBP30); prevalence differed between men and women and that of LBP30 increased with age. DISCUSSION-CONCLUSION: The prevalence of LBP as assessed by the National Health Survey is similar to that found in countries other than France. These estimates can be used as a reference for surveys in specific populations, provided that comparable methodologies are used.

Equivalence versus pragmatic trials for the economic evaluation of information and communication technologies; the case of polysomnography under telesurveillance in the diagnosis of sleep apnea syndrome.

This article deals with the choice of the appropriate protocols for the early economic evaluation of information and communication technologies, equivalence trial versus pragmatic trial. The reasoning put forward here is based on a concrete interrogation relative to polysomnography (PSG), a key diagnostic test for sleep apnoea syndrome (SAS). Is PSG under tele-surveillance more efficient than ambulatory PSG to diagnose SAS? After analyzing and discussing both advantages and limits of these two kinds of trial, we showed that one or the other can be used to obtain appropriate results. But in this particular example, we concluded that a pragmatic trial should be preferred, knowing that it requires a smaller sample of patients along with a narrower range of uncertainty concerning the evaluation of costs.

A cost-minimization study of telemedicine. The case of telemonitored polysomnography to diagnose obstructive sleep apnea syndrome.

OBJECTIVES: In a context where sleep laboratories are overwhelmed by a growing demand to diagnose obstructive sleep apnea syndrome (OSAS), efficient substitutive solutions to in-laboratory polysomnography should be found. To compare the effectiveness and costs of home unattended polysomnography (Hpsg) and telemonitored polysomnography (TMpsg), a cost minimization study was performed. METHODS: In a crossover trial, 99 patients underwent on two consecutive nights TMpsg and Hpsg according to a randomized order. A legibility recording criterion was retained to measure effectiveness. A microcosting study of TMpsg and Hpsg was performed. The risks to adopt home strategy or telemonitored strategy, according to different scenario chosen to reach the diagnosis in case of failure of Hpsg or TMpsg, were analyzed. RESULTS: The recording was considered to be ineffective in 11.2% of TMpsg (95% CI, 4.9-17.4) and in 23.4% (95% CI, 19.12-27.68) of Hpsg. The effectiveness differential was 12.2% (95% CI, 1.8-22.6) (p = .02). Assuming that in case of failure PSGs would be re-realized in the same condition to reach the diagnosis, then TMpsg could be selected if Hc/TMc (cost of Hpsg/cost of TMpsg) > 0.97; Hpsg could be selected if Hc/TMc < 0.76. If 0.76 < or = Hc/TMc < or = 0.97, the choice of TMpsg would be ambiguous. TMc was estimated to be $244, while Hc was $153 (Hc/TMc = 0.63). CONCLUSION: Unless some specific geographical situations generate significant transport costs, the implementation of a strategy based on unattended polysomnography at home is cost-saving compared to a telemonitoring strategy.

Needs and costs of sleep monitoring.

Sleep disorders have a high prevalence in the general population: insomnia (10-20% of adults), sleep apnoea syndromes (4-6%). They are responsible for high costs of investigations and treatment modalities. The investigations are usually done in sleep laboratories at the expense of cost in personnel and long waiting lists. Remote monitoring could be an alternative to sleep laboratory studies. The first aim was to determine the need for sleep remote recording in sleep medicine in Europe, to improve health delivery and to reduce investigation costs. An enquiry was sent to 500 sleep medicine providers in Europe. Response rate was 11%. Analysis showed that the main diagnosis is obstructive sleep apnoea in adults. Currently 2/3 of sleep studies are performed in laboratory: In-lab studies: Average cost for the health care is 390 EURO/study. The range is from 700 in Finland and Germany and 180 in Greece, Belgium and Sweden are around the mean. Ambulatory studies with EEG: Average cost is around 120 EURO/study i.e. 30% of in-lab cost. The range is from 180 EURO in Portugal to 70 EURO in Germany. 50% of users are not satisfied with their current practice of ambulatory monitoring although they have a clear need for this technique to increase monitoring capacity (88%), reduce cost of investigation (85%), improve sleep quality (60%), and obtain better acceptance from the patient (76%). The expectations from ambulatory monitoring are: high diagnostic sensitivity (86%) high reliability of equipment (92%) low interference with patient's habits (94%) It is worth noting that 74% of users do not expect a fully automated interpretation of data. The indications cited are screening and follow-up of SAS, epilepsy, Periodic Leg Movements and also insomnia and narcolepsy. As a second aim, a validation study has been set-up for an ambulatory recorder. The reproducibility of the system has been evaluated in 14 patients by 2 consecutive home recordings and was satisfactory in terms of total sleep time and apnoea-hypopnea index. Nevertheless a failure rate of 7% was observed which should be improved by a better ergonomy of the system. The third aim was a socio-economical analysis in Paris, in order to define the actual standard mean cost of a polysomnography in the lab (500 EURO) and in ambulatory (238 EURO) i.e. less than one half of the laboratory cost. The monography of the health care process for sleep medicine in Paris showed a delay of more than 10 years for diagnosis of SAS in 25% of the patients and up to 5 physicians visited before referral to the sleep lab. In 48% of the cases the primary physician visited is a GP. In conclusion, there is a clear need for ambulatory monitoring of sleep disorders to decrease the burden of cost and long waiting lists which is not well satisfied with the current health care system and commercially available equipment.

Economic studies and 'technical' evaluation of telemedicine: the case of telemonitored polysomnography.

Information and communication technology (ICT) is not yet integrated into current medical practice and frequently, organizational patterns of health care production are held responsible for this situation. However, and quite paradoxically, measures recently taken in France indicate that a preferential role is granted to ICT in order to promote the development of healthcare networks. In this context, one should carefully examine which factors, other than organizational ones, can explain the very slow diffusion of telemedicine. Actually, medical assessment of telemedicine is very seldom and the medical community is unable to appreciate the extent that this technology would modify the quality of care provided. Furthermore, and as a consequence of the former, there is no economic evaluation of telemedicine applications and its effects, in terms of productivity, remain virtual. In this article, based on an early evaluation of telemonitored polysomnography to diagnose sleep apnea syndrome, we show that it is possible, even at an experimental stage, to produce appropriate and convincing clinical results stating the true technological effectiveness (choice of an adequate clinical trial, selection of appropriate endpoints). Specific attention is given to the technical conditions in which the technology is assessed, we also provide most of the data that should be taken into account to foresee the major organizational transformations of the production processes. Our results show that early clinical ad hoc evaluations of telemedicine applications can be conducted promptly, providing strong clinical results and useful data for any forthcoming economic evaluation.

Transaction costs economics as a conceptual framework for the analysis of barriers to the diffusion of telemedicine.

Telemedecine has been talked about for more than 20 years, without it entering daily use with any success. Based on transaction costs economics, the present analysis of the exchange relationships between health care producers highlights certain characteristics of the current technical and legislative context, which leads to transaction costs. It also demonstrates that the introduction of telemedicine shifts the costs associated with agents' opportunism from patients to health-care producers themselves. All these costs may be considered nowadays to thwart the use of telemedicine. It is argued here that the Public Authorities and professionals of health care could act upon telemedicine in two fields: (1) intervention in the institutional environment aims notably at better defining the property rights of telemedicine, and so constitutes an unavoidable means of encouraging health-care producers to invest in new technology; and (2) implementation of organisational forms and mechanisms susceptible to regulating such telemedical relationships between health care producers-given the present institutional environment-constitutes an essential means for overcoming the immediate barriers blocking the diffusion of telemedicine.

[Fragile X syndrome is still unrecognized: efficacy of molecular diagnosis in mentally retarded probands]. / Le syndrome X fragile est encore méconnu: efficacité du diagnostic moléculaire chez les proposants avec retard mental.

BACKGROUND: The fragile X mental retardation syndrome is the most common cause of inherited mental retardation. Identification of the unstable mutation responsible for the disease has allowed the design of a fully reliable molecular test for the diagnosis of the disease and for genetic counselling (identification of clinically normal carriers and prenatal diagnosis). We started in July 1991 to search for the mutation in mentally retarded probands, with no known cause for their phenotype. We present the results of a 42-month experience. POPULATION AND METHODS: One thousand and one hundred fourty-nine probands were analysed. In case of a positive diagnosis, an extension of the molecular study to relatives was proposed. DNA samples were studied by Southern blot following EcoRI or EcoRI + EagI digestion. Clinical data were collected from referring clinicians. RESULTS: Seventy-three carriers of a full mutation were identified, belonging to 52 families. The mean age of the fragile X probands was 16 +/- 14 years, which is very surprising for a disease that causes significant manifestations by the age of 2 to 3 years. This indicates an insufficient knowledge about this disease in France. Most of the demands for the test were from clinical geneticists. This diagnosis is of major importance for genetic counselling, as illustrated by the following study of 108 women at risk in these families. CONCLUSIONS: The importance of an early diagnosis followed by an extended family study, for carrier screening and prevention of this severe disease, justifies molecular testing on any child with mental retardation or significant language delay of unknown cause, in the absence of clinical signs formally excluding a fragile X diagnosis.

[Cost-effectiveness study of 2 long-term home oxygen therapy management systems]. / Etude coût-efficacité de deux structures de prise en charge de l'oxygéno-thérapie de longue durée à domicile.

In France, home oxygen therapy for patients with chronic obstructive pulmonary disease (COPD) is carried out by nonprofit associations (NP) or profit-making health organisations (PM). In a retrospective pragmatic approach we analysed the costs and the effectiveness of these 2 types of structures delivering oxygen at home. Between July 1985 and March 1994, 234 patients were involved in the survival study (chosen as an effectiveness indicator), 24% in PM and 76% in NP. The economic appraisal was performed, from the insurer's point of view, on a representative sample of 61 patients and analysed in detail all the ambulatory costs for respiratory care. Patient survival was similar in both types of structures (Cox model). Oxygen therapy represented the largest share of the total ambulatory cost (81.6% in PM and 72.1% in NP). The NP structures were less costly for reasons linked to their preference for concentrator (p = 0.004 in a Wilcoxon test), all the other direct costs being non-statistically different. NP structures had a significant influence on a low level of ambulatory costs (adjusted OR = 10.98, p = 0.0004) in logistic regression. As oxygen treatment plays an important role in the variation of costs, further pragmatic studies should help to better understand what are the real motivations to choose one mode of oxygen administration more than an other and should determine factors that may sometimes lead physicians not to comply with clinical guidelines (actually a quarter of the patients did not have a PaO2 < 60 mmHg).

The cost of treating COPD patients with long-term oxygen therapy in a French population.

OBJECTIVE: In greater Paris and its surrounding (as it is in all France), oxygen is home delivered by not-for-profit (NP) associations or profit-making (PM) health organizations. Both are financed by the national health insurance. This dual context and the current economic climate justify an economic evaluation of all respiratory care for patients with COPD receiving long-term oxygen therapy (LTO). This pragmatic approach identifies the variables that have the greatest impact on direct medical costs and estimates the annual cost for respiratory care per COPD patient. DESIGN: Retrospective study. SETTING: Health insurance scheme for self-employed professionals (CANAM). PATIENTS AND METHODS: Between July 1985 and March 1994, 234 patients registered in CANAM files began LTO, 24% in the PM sector, 76% in the NP sector, mainly using concentrator (78%), mean age of 74 +/- 10 years, male predominance (74%), PaO2 of 56.2 +/- 10.5 mm Hg, FEV1/FVC of 43 +/- 15%, and 51% having 1 or more severe illness(es) associated. The economic appraisal was performed on a representative sample of 61 patients and measured the total resources consumption for respiratory care per COPD patient and per year (physician visits and tests, drugs, physiotherapy, oxygen therapy, hospitalizations for acute respiratory failure, transport costs). RESULTS: A quarter of the patients in each sector did not meet the LTO prescription guidelines (PaO2 > 60 mm Hg). For patients having their oxygen delivered by NP sector, the total ambulatory cost for respiratory care was lower ($4,506 per patient and per year vs $5,399) because they mainly used concentrator, all the other direct ambulatory costs being equal. The total annual cost for respiratory care of a COPD patient receiving LTO amounted to $11,672 (NP and PM sectors merged). Oxygen therapy represented 73% of the total ambulatory cost. In a multiple linear regression model, hospitalization represented the largest share of cost, significantly higher when PaO2 was 55 mm Hg or less ($2,287 per patient per year vs $8,717). In contrast, none of the covariates (age, sex, PaO2, FEV1/FVC) influenced at a significant level the total cost of visits, tests, drugs, and physiotherapy, amounting to $1,507. CONCLUSION: As oxygen treatment plays an important role in the variation of costs, further pragmatic studies should help to better understand what are the real motivations to choose one mode of oxygen administration more than another and should determine factors that may lead physicians sometimes not to comply with clinical guidelines.

[Cost-benefit analysis of vaccinal prevention of hepatitis B policy]. / Analyse coût-avantage d'une politique de prévention vaccinale de l'hépatite virale B.

Morbidity and mortality related to hepatitis B (VHB) induce heavy costs even in low endemia countries as France. Recent changes in patterns of virus transmission (increasing heterosexual contamination) lead to discuss the opportunity of re-evaluation of current VHB vaccine policies aiming primarily at most exposed populations (patients under dialysis, hospital workers, infants born to VHB+ mothers). Using cost-benefit methodology, in a context where epidemiological and economical pertinent data are quite rare, this article evaluates different strategies ("no vaccination", "universal vaccination" and "vaccination after screening") for four different populations with contrasted exposure (French general population, young men adults, homosexual men and intravenous drug users). The cost-benefit ratios indicate that thresholds are, for low-risk populations, very far from usually accepted values attributed to epidemiological and economical parameters. If vaccine is administrated to young men adults, the cost-per-hepatitis saved relative to "no vaccination" is 36,000 F. For high-risk exposure groups, vaccination may be considered cost-benefit for attack rates near (homosexual men) or greater (drug users) than that observed; optimal strategy could be obtained if drug users are screened and vaccined. This is the result of combination of relatively low incidence of VHB and variability of medical course and chronic sequalae. Consequently, if universal vaccination has to be chosen, it would mean that the implicit value attributed to the prevention of one hepatitis is very high.

[Comparative analysis of the costs of cytogenetic techniques and molecular biology techniques in the diagnosis of fragile X disease]. / Analyse comparée du coût des techniques cytogénétiques et de biologie moléculaire dans le diagnostic de la maladie de l'X fragile.

Mental retardation is sometimes due to chromosomal abnormalities. Most frequent illnesses are Down syndrome and Fragile X syndrome. Using a cost analysis, we try to see what diagnosis method is the most relevant to find chromosomic causes for mental retardation in an institutionalized male population. Two techniques are compared: cytogenetic technique and molecular biology technique. Four diagnostic strategies are identified. They all have the same effectiveness, but, costs vary. Results depend on prevalence rates in the epidemiologic literature on Fragile X syndrome and other chromosomic abnormalities. The least-cost diagnostic strategy is molecular biology then constitutional karyotype in case of a negative result. This strategy costs about 600 FF1991 less compared with Fragile X karyotype and about 120 FF1991 less than when molecular biology is done in second, for fixed prevalence rates (i.e. Fragile X prevalence rate between 4.5 and 10% and other abnormalities between 2.2 and 25%). Fragile X karyotype strategy has the highest cost whatever the prevalence rates. Those results are discussed when introducing female population and delay to test results for prenatal diagnosis.

[Cost benefits of intensive insulin therapy using injections, external pumps and implantable pumps]. / Coût-bénéfice de l'insulinothérapie intensive par injections, pompe externe et pompe implantable.

Since feasibility is now proven, cost-efficacy of external sub-cutaneous (EXT) and implantable programmable (IMP) insulin pumps needs to be compared to those of intensified conventional insulin therapy (CONV). Only metabolic efficacy and short-term direct costs are easily evaluable. We (WHO-CSII Study) and others have shown that glycemic control and severe hypoglycemia risk are slightly improved, while ketoacidosis risk and costs are aggravated with EXT vs CONV. We (CEDIT Study) and others have shown that glycemic control, mild and severe hypoglycemic risks are improved, with no increase in ketoacidosis rates although a doubling in costs with IMP vs CONV. Rigid interpretation of the above data would limit indications of insulin pumps to patients experiencing frequent hypoglycemias while on intensified conventional insulin therapy.

[Alcohol dependence. Financial aspect and socio-occupational consequences]. / La dépendance à l'alcool. Aspect financier et conséquences socio-professionnelles.

The financial cost of alcohol dependence was evaluated in 133 alcoholic patients. The main amount of money spent daily on alcoholic beverages was 94 French francs, a figure that was unrelated to the patients' monthly incomes and highest in those living alone and in those drinking exclusively out of home. These results suggest that the economic cost of alcohol dependence plays a key role in the socio-professional degradation of alcoholics.

[Cost-benefit analysis of amniocentesis in the prenatal diagnosis of chromosome abnormalities]. / Analyse coût-bénéfice du diagnostic prénatal des anomalies chromosomiques par amniocentèse.

The article presents a cost-benefit analysis of amniocentesis for detection of chromosomal anomalies based on data (1985/87) collected in the Marseille area. In this geographic area, it is possible to confront, in an exhaustive manner, pregnant women's access to amniocentesis and incidence of fetal anomalies due to chromosomal aberrations. Results show that prenatal diagnosis is highly cost-beneficial, the average cost of one "avoided" case of Down's syndrome being lower than the lifelong costs of care for such a child. However, the study emphasizes that the cost-benefit ratio is highly sensitive to the implicit value society affects to the loss of "normal" fetuses through spontaneous abortions provoked by amniocentesis and because of terminations of pregnancy following diagnosis of minor fetal anomalies. The study also shows that lowering maternal age limit for access to free-of-charge amniocentesis from the current 38 years of age to 35 would have been cost-beneficial. Such lowering of the maternal age limit is discussed and compared with other indications which might be used for systematic access to amniocentesis.