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Study Objectives: To assess the characteristics and outcomes of patients admitted to an ICU for severe accidental hypothermia, and to identify risk factors for mortality., Methods: All consecutive patients admitted to an ICU between January 1, 1979, and July 31, 1998, with a temperature of < or = 32 degrees C were retrospectively analyzed. Rewarming was always conducted passively with survival blankets and conventional covers. Prognostic factors were studied by means of univariate analysis (Mann-Whitney U and chi(2) tests) and multivariate analysis (logistic regression)., Results: Forty-seven patients were enrolled (mean +/- SD age, 61.7 +/- 16 years). Five patients had a cardiac arrest before ICU admission. Patient characteristics at ICU admission were as follows: temperature, 28.8 +/- 2.5 degrees C; systolic BP, 85 +/- 23 mm Hg; heart rate, 60 +/- 24 beats/min; Glasgow Coma Scale, 10.4 +/- 3.7; and simplified acute physiology score (SAPS) II, 50.9 +/- 27. Mechanical ventilation was necessary in 23 cases, and 22 patients in shock received vasoactive drugs. The mean length of stay in the ICU was 6.7 +/- 9 days. Eighteen patients (38%) died, but ventricular arrhythmia was never the cause. Univariate analysis identified several prognostic factors (p < 0.05): age (57 +/- 16 years vs 69 +/- 14 years), systolic arterial BP (93 +/- 20 mm Hg vs 71 +/- 21 mm Hg), blood bicarbonate level (23.5 +/- 5.2 mmol/L vs 16.6 +/- 6.2 mmol/L), SAPS II score (35.3 +/- 19.5 vs 72 +/- 21), mechanical ventilation (34% vs 81%), vasopressor agents (42% vs 82%), rewarming time (11.5 +/- 7.2 h vs 17.2 +/- 7 h), and discovery of the patient at home (2.3% vs 54.5%). The initial temperature did not influence vital outcome (28.9 +/- 2.6 degrees C vs 28.6 +/- 2.2 degrees C). Only the use of vasoactive drugs (odds ratio, 9; 95% confidence interval, 1.6 to 50.1) was identified as a prognostic factor in the multivariate analysis., Conclusion: Severe accidental hypothermia is a rare cause of ICU admission in an urban area. Its mortality remains high, but there is no overmortality according to the SAPS II-derived prediction of death. Shock, requiring treatment with vasoactive drugs, is an independent risk factor for mortality, while initial core temperature is not. It remains to be determined whether aggressive rather than passive rewarming procedures are better.

The aim of this study was to test the hypothesis that Doppler study of hepatic venous flow, reflecting right atrial pressures and right ventricular dysfunction, allows prediction of increased right atrial pressure and right ventricular dysfunction in patients with right ventricular infarction. The authors studied 30 patients (27 men, mean age 54 +/- 12 years) in sinus rhythm with acute inferior myocardial infarction who underwent right heart catheterisation and Doppler echocardiography including recording of regurgitant and hepatic vein flow within 48 hours of hospital admission. Hepatic venous flow was used to measure peak velocity and velocity time integrals (VTI) of the systolic (S), diastolic (D) and atrial (a) contraction waves. The fraction of systolic filling was calculated: VTI S/VTI S + VTI D. The pressure half-time of pulmonary regurgitant flow (PHT IP) was also measured. Using haemodynamic criteria (non-compliant right atrial pressure wave form or right ventricular end diastolic pressure/pulmonary capillary pressure > or = 0.8), patients were divided into two groups: Group 1: right ventricular infarction (VD+, N = 22). Group 2: no right ventricular infarction (VD-, N = 8). No correlation was observed between Doppler parameters of hepatic venous flow and haemodynamic data, in particular right atrial pressure and pressure wave form. Moreover, no statistically significant difference was observed between the two groups with respect to the Doppler parameters derived from hepatic venous flow. On the other hand, the results confirmed good diagnostic performance of Doppler analysis of pulmonary regurgitant flow: sensitivity 80%, specificity 83%, positive predictive value 94%, negative predictive value 55%. The authors conclude that, in patients with acute inferior wall infarction, Doppler analysis of hepatic venous flow does not allow assessment of right atrial pressure or of ischaemic right ventricular dysfunction.

Ursodeoxycholic acid (UDCA) is the only approved treatment for primary biliary cirrhosis (PBC). However, the benefit from UDCA therapy on the progression of PBC from its early stage towards extensive fibrosis and cirrhosis has not been clearly shown. The aim of this study was to assess the effect of UDCA therapy on liver fibrosis progression in PBC. A Markov model was used to analyze the progression rates between early and late histologic stages in 103 patients with PBC enrolled in a randomized, double-blind, placebo-controlled trial of UDCA. Early stage was defined by the presence of portal and periportal lesions without extensive fibrosis, whereas late stage was defined by the presence of numerous septa, bridging fibrosis, or cirrhosis. A total of 162 pairs of liver biopsy specimens were studied. The model accurately described the observed data. UDCA therapy was associated with a 5-fold lower progression rate from early stage disease to extensive fibrosis or cirrhosis (7% per year under UDCA vs. 34% per year under placebo, P <.002), but was not associated with a significant difference in regression rates (3% per year under both UDCA and placebo). At 4 years, the probability of UDCA-treated patients to remain in early stage disease is 76% (95% confidence interval: 58%-88%), as compared with 29% (15%-52%) in placebo-treated patients. In conclusion, UDCA therapy significantly delays the progression of liver fibrosis in PBC. Markov modeling should prove useful in assessing the efficacy of future medical treatments in clinical trials involving histologic endpoints.

Purpose: To develop and evaluate a scale for assessment of the methodological quality for clinical investigations of radiologic studies., Materials and Methods: A scale was developed that included methodological standards compiled from established sources for assessing the methodological quality of study designs in clinical research and characteristics related to biases commonly observed in clinical radiologic research. The scale was composed of 15 standards and was tested with the results of 96 studies on imaging of liver hemangioma. Interrater reliability was measured between two observers by using percentage agreement and kappa statistics. Interrater reliability between two observers for a composite quality index that encompassed the 15 standards was measured with the intraclass correlation coefficient., Results: Agreement between the two observers was almost perfect (kappa value, 0.8-1.0) for 11 standards and substantial (kappa value, 0.74-0.78) for four standards. Agreement between the observers with regard to the composite quality index also was high (intraclass correlation coefficient r, 0.91 [95% CI: 0.87, 0.94])., Conclusion: The scale appears to be reliable for the assessment of methodological quality of clinical investigations of radiologic studies.

Background: Automated electrophoresis combined with enzymatic cholesterol staining might improve routine assessment of LDL- and HDL-cholesterol (LDLC and HDLC), as an alternative to the Friedewald equation and precipitation. A new method (Hydrasys; SEBIA) that adapts the cholesterol esterase/cholesterol oxidase reaction within urea-free gels was evaluated., Methods: Fresh sera from 725 subjects (512 dyslipidemics) were analyzed by electrophoresis, in parallel with sequential ultracentrifugation, beta-quantification, calculation, and precipitation., Results: Electrophoresis was linear up to 4 g/L cholesterol, with a detection limit of 0.042 g/L cholesterol/band. Within-run, between-run, between-batch, and between-operator imprecision (CVs) were 1.6%, 2.0%, 1.5%, and 2.7% for LDLC, and 3.9%, 4.3%, 5.5%, and 4.9% for HDLC, and remained unchanged up to 6.3 g/L plasma triglycerides (TGs). Precision decreased with very low HDLC (<0.25 g/L). Serum storage for 3-7 days at +4 or -80 degrees C did not interfere significantly with the assay. Agreement with beta-quantification was stable for LDLC up to 5.07 g/L (r = 0.94), even at TG concentrations >4 g/L (r = 0.91). Bias (2.88% +/- 12%) and total error (7.84%) were unchanged at TG concentrations up to 18.5 g/L. Electrophoresis predicted National Cholesterol Education Program cut-points with <0.04 g/L error, exactly and appropriately classified 79% and 96% of the subjects, and divided by 2.4 (all subjects) and 5.8 (TGs >1.5 g/L) the percentage of subjects underestimated by calculation. One-half of the patients with TGs >4 g/L had LDLC >1.30 g/L. For HDLC, correlation was better with precipitation (r = 0.87) than ultracentrifugation (r = 0.76). Error (-0.10% +/- 26%) increased when HDLC decreased (<0.35 g/L). Direct assessment of the LDLC/HDLC ratio detected 45% more high-risk subjects than the calculation/precipitation combination., Conclusions: Electrophoresis provides reliable quantification of LDLC, improving precision, accuracy, and concordance over calculation, particularly with increasing plasma TGs. Implementation of methods to detect low cholesterol concentrations could extend the applications for HDLC assessment.

In medical research, comparing two groups of patients occurs frequently. The basic principles of comparison and the usual statistical tests--according to the types of variables and the choices of sampling methods--are presented. Elements needed for the computation of the size of a comparative study are given.

The analysis of routinely collected surveillance data is an important challenge in public health practice. We present a method based on a hidden Markov model for monitoring such time series. The model characterizes the sequence of measurements by assuming that its probability density function depends on the state of an underlying Markov chain. The parameter vector includes distribution parameters and transition probabilities between the states. Maximum likelihood estimates are obtained with a modified EM algorithm. Extensions are provided to take into account trend and seasonality in the data. The method is demonstrated on two examples: the first seeks to characterize influenza-like illness incidence rates with a mixture of Gaussian distributions, and the other, poliomyelitis counts with mixture of Poisson distributions. The results justify a wider use of this method for analysing surveillance data., (Copyright 1999 John Wiley & Sons, Ltd.)

Background: Cigarette smoking is associated with a more severe course of Crohn's disease, but individual factors determining this effect are poorly known and it is not clear whether smoking cessation is associated with an improvement in the disease activity., Aim: To assess the factors determining the harmful effect of smoking in individuals with Crohn's disease., Methods: A total of 622 consecutive patients with Crohn's disease and Crohn's disease activity index <200 were enrolled in a prospective 12-18 month cohort study. Patients were classified as current smokers, former smokers, or non-smokers. Alcohol consumption, oral contraceptive use, body mass index, and blood lipid levels were also recorded. The main outcome measure was the rate of flare-up., Results: A total of 139 current smokers (46%) developed a flare-up, vs. 79 non-smokers (30%) and 13 former smokers (23%). The relative risk of flare-up adjusted for confounding factors was 1.35 (1.03-1.76) in current smokers. This risk was increased in patients with previously inactive disease and in those who had no colonic lesions. It became significant above a threshold of 15 cigarettes per day. Former smokers behaved like non-smokers. Obesity, dyslipidaemia, and alcohol consumption had no significant effect., Conclusions: Current smoking, particularly heavy smoking, markedly increases the risk of flare-up in Crohn's disease. Former smokers have a risk similar to that of non-smokers.

The aim of this study is to evaluate ambulatory respiratory drug sales data as health indicators for the short-term effects of ambient air pollution in the city of Le Havre. Daily respiratory drug sales data were crossed with daily ambient air concentrations of sulfur dioxide (SO2), nitrogen dioxide (NO2), and black smoke (BS) using an autoregressive Poisson regression model adjusting for time trends, seasonal variations, influenza epidemics, and weather. Relative risks (RR) were expressed for an increase of two standard deviations above the mean of each pollutant. Respiratory drug sales were associated with most pollutants studied with lags varying from 1 to 9 days. For daily mean concentrations of BS, RR = 1.037 (95% confidence interval (CI) 1.009-1.066) for lag 1 and RR = 1.052 (95% CI 1.023-1.081) for lag 8. For daily mean concentrations of N02, RR = 1.033 (95% CI 1.001-1.066) for lag 1 and RR = 1.046 (95% CI 1.014-1.079) for lag 8. RR observed with a daily 1 h maximum of SO2 were RR= 1.027 (95% CI 1.004-1.051) for lag 3 and RR= 1.032 (95% CI 1.009-1.056) for lag 9. Our study concludes that ambulatory respiratory drug sales data could be useful for epidemiological surveillance of air pollutant health effects.

Background: Women with Crohn's disease are usually advised not to take oral contraceptives, but, unlike smoking, there is no clear association between current oral contraceptive use and more severe disease., Aim: To assess the effect of oral contraceptive use on the clinical course of Crohn's disease., Patients: 331 women, aged 16-50 years, with Crohn's disease and Crohn's disease activity index <200, were enrolled consecutively during a one year period. Patients were classified at inclusion as oral contraceptive users or non-users and smokers or non-smokers., Methods: A prospective 12-18 month cohort study was used. The main outcome measures were flare up rate and time to flare up., Results: In total, 134 women used oral contraceptives, in most cases low oestrogen formulations. During the study period, 61 oral contraceptive users (46%) developed a flare up, compared with 85 non-users (43%). The hazard ratio for oral contraceptive use was 1.11 (95% confidence interval 0.80 to 1.55). Variables associated with flare up were smoking status, recently active disease, baseline Crohn's disease activity index, and presence of anoperineal lesions. The same results were obtained when the analysis was restricted to patients eligible for a relapse prevention trial., Conclusion: Unlike smoking, oral contraceptives have no effect on Crohn's disease activity.

Background/aim: The aim of this study was to estimate the annual number of cases of hepatitis C virus transmission from infected patients to uninfected surgeons or nurses due to percutaneous injury during invasive procedures., Methods: The risk of transmission was estimated using a model involving three probabilities: A, that a health care worker sustains at least one percutaneous injury during a procedure; B, that 1 to 10% of patients are seropositive for hepatitis C virus; and C, that infection by this virus is transmitted to the Health Care Worker after such exposure. Probability A was estimated from the results of 2 French multicentric prospective trials. Probability C was estimated from the results of 9 international prospective studies. A ten-fold decreased risk was assumed for surgeons who wear gloves and use solid-bore suture needles., Results: During a single procedure, the estimated probability of hepatitis C virus transmission from an infected patient to an uninfected surgeon ranged from 4.2x10(-5)% to 4.2x10(-4)%, and from 2.98x10(-6)% to 2.98x10(-5)% to an uninfected nurse. For surgeons, the estimated annual cumulative risk of occupational infection ranged from 0.01% to 0.1% (1 in 10000 to 1 in 1000), and for nurses from 0.0054% to 0.054% (1 in 18700 to 1 in 1900)., Conclusions: Between 2 and 21 surgeons out of a total 20000 are estimated to acquire occupationally-related hepatitis C virus infection, and between 16 and 167 nurses out of a total 300000. These estimates strongly justify introducing preventive measures to protect health care workers from bloodborne infection.

Using clinical predictors, we evaluated clinical case definitions of influenza during the 1995-1996 outbreak in France. Thirty-five general practitioners collected virological specimens and clinical data. Predictors of influenza virus infection were selected with logistic regression models. The results varied with the influenza virus subtype: temperature of >38.2 degrees C, stiffness or myalgia, rhinorrhea, and cough were predictive of influenza A/H3N2, whereas fatigue, lacrimation or conjunctival injection, and the absence of stiffness or myalgia were predictive of influenza A/H1N1. On the basis of this analysis and data from the literature, 12 clinical case definitions were evaluated for their abilities to diagnose influenza virus infection. They were associated with positive predictive values of 27% to 40% and negative predictive values of 80% to 91%. We conclude that focused studies evaluating clinical case definitions of influenza with use of subsets of patients should accompany population-based disease surveillance for optimal estimates of the disease burden associated with influenza epidemics.

Background: In France health insurance coverage is universal (see note at the end of the text), nevertheless some people remain uninsured. In this high-risk population, the lack of insurance coverage contributes to the aggravation of health, by reducing access to medical care. In 1992, the Baudelaire consultation was incorporated into the outpatient clinic of Saint-Antoine hospital (Paris, France), to provide the uninsured with the same access as any other patient--but free of charge--to medical care. Social care was also provided in particular by assisting the uninsured in applying for insurance coverage. Our objectives were to quantify the delay in obtaining insurance coverage and to study whether the sociodemographic characteristics of these patients were associated with inequalities in terms of delays., Methods: All patients attending the consultation for the first time in 1994 were included (n = 623). Because of differences linked to the French social security system, analysis was performed into two groups according to the existence of a prior insurance coverage. Delay in obtaining or recovering insurance coverage was considered as the key variable. The socio-demographic factors linked to the rates of access to insurance coverage were determined using Cox proportional hazards regression models. We also examined the factors linked with the existence of a prior insurance coverage by logistic regression modeling., Results: Within one year 96% of the patients who had had insurance coverage in the past, and 63% of the patients who had not, were insured. No factor, whether nationality, educational level, socio-professional category, family situation, type of housing, made of income was found to be linked with obtaining or recovering insurance coverage. However, nearly all these factors were related with the existence of prior insurance coverage., Conclusions: Our approach of systematically providing social care allows 70% of uninsured patients to obtain insurance coverage within one year. This approach probably contributes to an improvement by facilitating access to mainstream health care. Moreover, no difference in delay in obtaining insurance coverage was found associated with sociodemographic characteristics.

Objective: To study the effect of the protease inhibitor indinavir on body weight and body composition of subjects with HIV-related wasting., Design: Prospective measurement of body weight in patients who had wasting and were treated with indinavir. A subgroup of 16 representative patients also underwent a metabolic study that included measurements of body composition (skinfolds and bioelectrical impedance) and food intake. Seven from this subgroup who did not have chronic diarrhoea also underwent indirect calorimetry for measurement of resting energy expenditure; the nine patients with wasting and chronic diarrhoea had measurements of faecal losses and intestinal permeability using the lactulose-mannitol test., Setting: A tertiary care university hospital., Patients: Two hundred and fourteen HIV-infected patients with wasting (less than 95% of usual body weight) had their body weight measured at day 0; 186 patients had a second body weight measurement within the first 100 days of treatment, and 160 patients were weighed a third time, at a median of 176 days., Results: Body weight increased significantly (P < 0.0001) during treatment, whatever the degree of weight loss at baseline. After a median of 176 days on treatment, body weight had increased in 119 out of the 160 patients followed (74.4%; mean weight gain, 6.3+/-SD 3.8 kg; range, 1-18 kg), had not changed in 13 (8.1%) and had fallen in 28 (17.5%; mean weight loss, 4.2+/-3.0 kg; range, 1-12 kg), relative to baseline. Overall, 119 out of the 214 patients (55.6%) from the initial population gained weight. Fat mass, fat-free mass and body cell mass increased significantly in the 16 patients who underwent metabolic studies, together with energy, protein and lipid intake. In the patients with chronic diarrhoea, intestinal permeability improved but there was no change in intestinal losses. In patients who had wasting but not chronic diarrhoea, resting energy expenditure did not change significantly. Body weight changes correlated with changes in the CD4+ cell count (r = 0.882; P = 0.00001) and, to a lesser extent, with changes in the viral load (r = -0.466; P = 0.047)., Conclusion: Indinavir significantly improved the nutritional status of these patients with HIV-related wasting.

Weight loss is significant in patients with HIV and chronic diarrhea. The aim of our study was to test for the links between weight loss, the level of food intake, and the severity of diarrhea and nutrient malabsorption. One hundred and sixteen patients with HIV and chronic diarrhea underwent a standardized gastrointestinal and nutritional evaluation, which included a questionnaire on diarrhea, a prospective estimation of food intake, a measurement of blood parameters and fecal lipid and nitrogen outputs, a stool examination for bacteria and parasites, and upper and lower digestive tract endoscopy. Diarrhea resulted from an infection by Cryptosporidia, Microsporida, or other pathogens in 22%, 20%, and 13% of the patients, respectively. Diarrhea appeared idiopathic in 45% of the patients. A significant negative correlation existed between the severity of weight loss and the levels of nutrient intake (p < .005), and a significant positive correlation between the severity of weight loss and stool frequency (p < .01). Multiple linear regression identified low caloric intake and high stool frequency as predictive of weight loss. No significant correlation was found between weight loss and the parameters of malabsorption, either by bivariate study or multiple regression. These results suggest that, in patients with HIV and chronic diarrhea, the degree of wasting is significantly related to the levels of dietary intake and the clinical severity of diarrhea, but not to the extent of nutrient malabsorption.

Objectives: To determine the risk and predictive factors for colonic extension in patients with ileal Crohn's disease., Methods: One hundred and fifty patients with ileal Crohn's disease and no specific colonic lesions on initial colonoscopy were studied retrospectively (median follow-up: 51 months)., Results: Twelve patients (8%) developed colonic lesions. Ten-year cumulated risks (95% confidence interval) for colonic extension were 17.2% (range: 5.8-28.6) in the whole group, and 22.4% (range: 8.7-36.1) in the group of 86 patients with repeated colonoscopy. Young age at diagnosis was the only factor predicting colonic extension. Seven patients with colonic extension required immunosuppressive therapy but none underwent surgery., Conclusion: Ileal Crohn's disease has a low tendency for colonic extension. Colonic extension has no major prognostic implications.

Molecular markers can improve staging and predict aggressive clinical behavior in esophageal cancer, thus helping to define appropriate therapeutic protocols and to identify patients who will benefit from surgery. We therefore characterized, by Northern blot and/or immunohistochemistry, the relative expression of three effectors involved in the invasion, angiogenesis, and dissemination of tumor cells in esophageal cancer versus nontumoral mucosae: (a) stromelysin-3 (ST3), a member of the metalloproteinase family; (b) basement membrane 40/secreted protein acidic and rich in cysteine (BM-40/SPARC), an extracellular matrix-associated protein involved in angiogenesis; and (c) the hepatocyte growth factor receptor MET, which triggers the scattering of epithelial cells. Results were analyzed in relation to clinicopathological parameters (cpTNE) including tumor size (T), lymph node status (N), periesophageal tissue invasion (E), disease recurrence, and overall survival. The ST3, BM-40/SPARC, and MET genes were found to be overexpressed in tumor samples compared to control mucosa. BM-40/SPARC and MET mRNA levels were not linked to any one of the cpTNE, indicating that this overexpression occurs at an early stage of neoplastic progression. In contrast, ST3 expression, identified by immunohistochemistry in fibroblastic cells surrounding neoplastic islets, correlated with tumor size and periesophageal tissue invasion. Of the 36 patients studied, those with high ST3 levels had shorter disease-free survival than those with low levels, but there was no relationship between the cpTNE and disease recurrence or survival. Our study demonstrates that ST3, BM-40/SPARC, and MET are involved in different steps of esophageal carcinogenesis and that ST3 overexpression is a marker of aggressive clinical behavior. We conclude that in esophageal cancer, ST3 might help to assess survival and the risk of recurrence after surgical resection.

SITUATION IN FRANCE: The prevalence of hepatitis C virus (HCV) infection in the French population is estimated at 1%, a level similar to that in other western countries. USUAL CONTAMINATION ROUTES: Epidemiological studies, together with gene typing, have made it possible to distinguish transmission modes. A history of intravenous drug abuse or transfusion is found in 60 to 80% of all subjects infected by the HCV. Other documented modes of contamination include hemodialysis, organ transplantation, accidental occupational-related puncture and mother-infant transmission. OTHER ROUTES: Sexual or intra-familial nonsexual transmission is uncommon and related to the length of exposure and the stage of HCV infection in the "source" subjects. Cases of HCV transmission have been reported during medical procedures. Currently the mode of of transmission is unknown in 20 to 40% of the cases.

Our objective was to evaluate influenza vaccine effectiveness during an influenza epidemic by means of a matched case-control study. The study was performed by 35 general practitioners who collected specimens for influenza virus testing from 610 patients who consulted for infectious syndrome: 168 (28%) were influenza-positive. Two designs were used for selecting controls to take into account the high incidence-rate of influenza-like illness and the various possible protective effects of the vaccine. A first disease-free control matched for age and sex was selected during the same week as the case. A second control matched for age and sex was selected at the end of the epidemic period, irrespective of disease history during the epidemic period. Upper and lower bounds of vaccine effectiveness can be derived from these case-control designs. After adjustment for chronic conditions and exposure to an index case, analysis of the matched-pairs whose case was influenza-positive showed, with the first group of controls, an influenza vaccine effectiveness of 68% (95% CI, 10% to 88%) and, in the second group, 53% (95% CI, -19% to 82%). Among the pairs whose case was negative for influenza, vaccine effectiveness was, respectively, 31% (95% CI, -17% to 59%) and 12% (95% CI, -47% to 47%). Vaccine effectiveness was highest for the H3N2 subtype whose vaccine strain was identical to that of the wild-type strain. The results suggest that influenza vaccine is effective in the field in preventing influenza morbidity.

Study Objectives: To discover if continuous computerised collection of morbidity data through a medical practice based sentinel network can be used to monitor influenza-like illness (ILI) epidemics. To obtain rough estimates of influenza vaccine effectiveness., Design: Continuous passive surveillance of ILI through a computerised network of voluntary sentinel general practitioners (SGPs) in France (Sentinelle system)., Setting: Five hundred SGPs practices., Participants: Since 1984, SGPs updated a database with information on eight communicable diseases including ILI, via videotext terminals. Each ILI case is defined by the association of a sudden fever of 39 degrees C or above, respiratory symptoms, and myalgias. An ILI epidemic is detected when the national weekly incidence rate exceeds a seasonal threshold for two successive weeks., Main Results: An ILI epidemic was reported from November 1995 to January 1996. In total, 13,951 individual cases were reported by SGPs during the epidemic period. The size of the epidemic (number of patients consulting a GP) was estimated to be 2,370,000 subjects. Maps of the epidemic showed that all regions have reported a high level ILI activity. The attack rate was the highest in school age children (13.5/100) and decreased as the age rose. Nearly 6% of the reported ILI cases among adults and elderly were vaccinated. The flu vaccine effectiveness against ILI was estimated to be 66% (95% CI 73%, 92%), ranging between 83% (95% CI 73%, 92%) among the subjects aged 15 to 24 years old to 16% (95% CI -12%, 44%) among the subjects aged 75 years or older., Conclusions: The Sentinelle system demonstrated adequate sensitivity and timeliness regarding ILI epidemic. Moreover, results of the monitoring were made available on the internet to increase the dissemination of information. Also, estimates of influenza vaccine effectiveness have been easily obtained. Altogether, they represent key points for the control of crisis situation such as ILI epidemics or pandemics.

In France, the entire population theoretically has access to health coverage, but in fact a section of the poorest population does not. Institutions have therefore been set up to provide medical care for the destitute. The objectives of this study were to describe the social characteristics of the HIV-positive destitute population attending an out-patient clinic providing free health care for the destitute in a Paris University Hospital, to compare their clinical-epidemiological characteristics with those of non-destitute HIV-positive patients, and to evaluate the quality of their care. We performed a historical prospective study wherein a cohort of 115 HIV-positive destitute patients (defined as having no health coverage at their first consultation) was compared with a control cohort of 183 HIV-positive non-destitute patients attending the same clinic. Ninety-five per cent of the destitute patients had no stable employment, 32% had no source of income, 75% had no permanent residence and 27% were i.v. drug abusers. Fifty-nine per cent were foreigners, most of whom had legal residence papers and had been in France for more than 3 years. When comparing the control and the destitute groups, the latter had a three times greater risk of developing tuberculosis (RH = 3.2, CI 95% = [1.1-9.4]). Medical compliance, access to antiretroviral treatment and hospitalization were identical in both groups. No difference was observed in terms of occurrence of a new AIDS-related disease during follow-up when full-blown AIDS before entry, CD4 count at entry and transmission group were taken into account in multivariate analysis. From the moment that destitute patients attended this adapted medico-social facility, their access to care was the same as, if not better than, that of the other patients. The development of out-patient medico-social facilities for HIV-positive destitute patients must be a public health priority even for those countries theoretically providing generalized health coverage.

Background: There are two types of inflenza surveillance techniques: qualitative laboratory-based surveillance and quantitative medical practice-based surveillance. The former is of great importance in isolating new strains of the virus, which helps in the decision-making process concerning the composition of the vaccine, and the latter provides estimates of morbidity, mortality or economic impact as a result of infection from the influenza virus. Rapid methods such as immunoflourescence (IF) or immunocapture assays (ICA) are now available for diagnosis of influenza infections. However, little is known about the use of these methods for influenza surveillance purposes., Aims: To evaluate the feasibility of a rapid influenza diagnosis in ambulatory conditions, and to investigate the therapeutical outcomes of patients suffering from influenza-like illness (ILI) in relation to the virological diagnoses., Method: During the 1994-1995 influenza season, 130 patients presenting with ILI symptoms (< 36 hours) to 33 general practitioners (GPs) were included in a prospective study. Two nasal swabs and one throat swab per patient were collected and sent to the laboratory within 12 hours. Information concerning therapeutical outcomes was recorded during examination. Specimens were analysed using the immunofluorescence (IF) method and antigen immunocapture assay (ICA)., Results: Sixteen influenza A (12%) and 19 influenza B (15%) infections were diagnosed. The overall rate of influenza positive specimens was 17% in the pre-epidemic period and 31% during the epidemic (P = 0.1). The rates of usable specimens for IF assay, nasal ICA and throat ICA were 46%, 100% and 99% respectively. The combination of these three collections ensured a highly sensitive influenza virological diagnosis. There were no differences in therapeutical outcomes between the influenza positive and negative cases. The GPs prescribed antibiotics in 60% of the cases for a mean duration of 7 days (+/- 1.2). The mean duration of sick leave was 3.4 days (+/- 1.6). Twelve patients (four influenza positive, eight influenza negative) had been vaccinated at the beginning of the winter. The practitioner's intuition concerning 'which patient should be tested for influenza virus' did not prove useful in improving the aptness of virological diagnoses in the field of influenza surveillance., Conclusion: The only way to estimate the true impact of influenza is to carry out a systematic virological sampling based on a sensitive clinical definition and using sensitive laboratory methods.

Unlabelled: Artificial nutrition prior to bowel resection has not been evaluated fully. The aim of the present study was to assess the effects of preoperative artificial nutrition upon postoperative complications, length of resected bowel and relapses of Crohn disease., Results: Between 1990 and 1994, 108 consecutive patients underwent bowel resection for Crohn disease. Thirty nine patients had received exclusive enteral nutrition (n = 14) or parenteral nutrition (n = 25) for 19 +/- 10 days. Patients who had received artificial nutrition were more malnourished and had complicated Crohn disease (fistulae, abscesses) more often than patients operated without artificial nutrition. After 19 days of artificial nutrition, the nutritional state of patients was not significantly improved. Postoperative complication rate was higher in patients operated after artificial nutrition (33 vs. 16%; P = 0.03). Using multivariate prognosis analysis, the extent of colic resection was significantly associated with postoperative complications (P = 0.0003). Length of resected bowel and relapse rates were similar in patients with or without preoperative nutrition., Conclusion: Artificial nutrition prior to bowel resection for Crohn's disease is indicated in patients with the most severe form of the disease. A preoperative nutrition of 19 days does not seem to reduce postoperative complications nor the length of resected bowel.

Objective: This epidemiologic study was undertaken after a cluster of five cases of rare forms of cancer (bone sarcoma, non-Hodgkin's lymphoma) had been observed among biomedical research workers at the Pasteur Institute in Paris to ascertain whether their disease was connected with exposure during this research., Methods: A mortality study included 3765 people who worked at the Pasteur Institute between 1971 and 1986 and were followed until the end of 1987. Within this cohort a nested case-referent study included 23 cases of cancer [non-Hodgkin's lymphoma (6), multiple myeloma (1), leukemia (3), pancreatic cancer (7), bone cancer (3), brain tumor (3)], and four referents per case, matched for gender and year of birth., Results: Total mortality from cancer was less than expected, the standardized mortality ratio (SMR) being 72 for the men and 82 for the women. Among the women the proportion of pancreatic cancer cases was larger than expected [SMR 490, 95% confidence interval (95% CI) 158-1144], as was the number of brain cancer cases (SMR 239, 95% CI 48-696). Among the men, mortality from bone cancer was greater than expected (SMR 553, 95% CI 62-2006). In the nested case-referent study, more cases than referents had worked in the areas of molecular biology [odds ratio (OR) 7.1, 95% CI 1.5-33] and microbial genetics (OR 6.7, 95% CI 1.3-35). These cases especially included non-Hodgkin's lymphoma and bone cancer. Associated with this finding was the fact that more cases had used certain chemicals, including ethidium bromide, acrylamide, methylnitronitrosoguanidine and ethylmethanesulfonate, and radioactive compounds (essentially 32phosphorus)., Conclusions: As the products used are potent genotoxicants, the present findings suggest that work in biomedical research might well involve an increased risk of certain types of cancer; this conclusion should be balanced by the fact that two of the five index cases were included in the mortality study and four in the nested case-referent study.

Study Objectives: This study aimed to assess total influenza mortality among the elderly (> or = 75 years old) in France, and to evaluate how many deaths may have been avoided through vaccination during the past 10 years., Design: The monthly mortality rates related to different causes among the elderly were obtained from the national mortality statistics for the period 1978-90. For each cause, the proportion of the registered death rate attributable to influenza was estimated using time series models. Each model analysed the registered death rate for the considered cause as a linear function of the registered influenza death rate for that month, the secular trend, and the seasonal variations. This yielded yearly regression coefficients for influenza. Formulas were subsequently developed to estimate the death rates avoided as a result of influenza vaccination according to the level of vaccine coverage and the hypothetical effectiveness of the vaccine., Main Results: Between 1980 and 1990 registered influenza death rates ranged from 11-81 per 100,000. The number of deaths attributable to influenza but registered as resulting from another cause was up to eight times the number of deaths registered as influenza. Total influenza death rates were estimated as ranging from 28 per 100,000 (1988-89) to 482 per 100,000 (1985-86). At the same time it was estimated that the use of influenza vaccine avoided from 7 per 100,000 deaths in 1981-82 to 697 per 100,000 deaths in 1989-90, depending on the intensity of the epidemic, the vaccine coverage, and the vaccine effectiveness., Conclusions: These results support the policy of promoting influenza vaccination among the elderly.

A large number of papers are regularly published about anti-flu vaccine with discordant results regarding their efficacy. Through a recent review the efficacy of the vaccine has been evaluated both in terms of the immune response, the protection against clinical disease, but also as regards the impact from an epidemiological and economic point of view. In the majority of papers in which the immune response was studied before and after vaccination a 60 to 100% case of protection was obtained serologically by measuring the protective antibodies. These levels varied as a function of the type of the vaccination (inactive or living) and also of the immune state of the subject. In subjects of more than 60 years of age the immune response was 1.5 to 2 times less that in the young adult. The protection against clinical disease in children and adults is of the order of 40 to 70%, according to whether the infection is confirmed or not. On the other hand the vaccine is less effective in the elderly subjects, but gives a protection of the order of 75% protection against complications or of mortality linked to influenza. Finally there are a certain number of epidemiological and economic arguments which would justify the vaccine use on a large scale.

We studied the consequences of misdiagnosis of intrauterine growth retardation (IUGR) for preterm elective cesarean section among live singleton newborns in two teaching hospitals in Paris between 1978 and 1983. The population studied comprised the 16,540 babies who were normal for date, according to the 10th percentile of the reference curve established in this population. For 118 of these infants, IUGR had been diagnosed during pregnancy. The preterm elective cesarean section rate was 12.7% among newborns for whom IUGR was erroneously diagnosed, compared to 1.2% among those for whom IUGR was not diagnosed. The relationship between preterm cesarean section and misdiagnosis of IUGR still existed (odds ratio: 5.2, 95% CI: 2.1-12.9) after taking into account obstetric history and hypertension during pregnancy. Our results show that after diagnosis of IUGR, supplementary tests are essential to confirm fetal distress and consequently avoid unnecessary interventions.

This paper presents the application of a technique from the earth sciences, the "kriging" method, to the field of geographic epidemiology. Both the principles of the method and the basic equations are given. A key advantage of the method is that it relies on an analysis of the spatial variability of the data and allows the representation of the variable under study as a continuous process throughout a country. Application of the kriging method to the geographic distribution of an epidemic of influenza-like illness in France is discussed.

We studied the fetal and maternal characteristics that affect the diagnosis of intrauterine growth retardation and lead to variations in the sensitivity, specificity and predictive values. The population comprised the 18,166 women who consulted and delivered in two teaching hospitals in Paris from 1978 to 1983. Specificity was lower when a child was born before 37 weeks, with a small weight-for-gestational age, and when the mother had experienced complications during either her obstetric history or current pregnancy. Conversely, sensitivity was higher when these maternal and fetal characteristics were present. Positive predictive values rose in the presence of a risk factor for small-for-dates, but the rise was smaller than would have been expected if sensitivity and specificity had remained at the levels observed in the low-risk group.