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A Flahault

Publications and source records attributed to A Flahault.

At least 37 records · Page 2Linked to original sources
PubMed2003

A mathematical model for evaluating the impact of vaccination schedules: application to Neisseria meningitidis.

A mathematical model is described which determines the impact of a schedule of vaccination on the time course of a certain class of diseases. The data are the demographic variables and parameters and age-dependent non-fatal and fatal case rates. Given the age- and time-dependent rates of vaccination including coverage and corresponding efficacies, various schedules may be distinguished by either the absolute numbers of cases and deaths avoided or the numbers of cases and deaths avoided per dose of vaccine. The model was applied to meningo-coccal serogroup C disease in France. The outcomes of six different vaccination schedules were examined. In absolute terms, a schedule in which all individuals aged between 2 and 20 years were vaccinated performed best, but this schedule and that in which only 1-year olds were vaccinated performed equally and best in terms of cases prevented, but not lives saved, per dose.

Adolescent↗
PubMed2002

Lung and thorax development during adolescence: relationship with pubertal status.

The aim of the present study was to define reference values for lung volumes and the lung transfer factor for carbon monoxide (TL,CO) for an adolescent population using thoracic volume index (TVI) and an index of pubertal stage in order to account for the variation in growth pattern between adolescents. TVI, pubertal stage by Tanner scale (PST), time since menarche, functional residual capacity measured using the helium-dilution technique, vital capacity, total lung capacity and TL,CO measured using a steady-state method were determined in 51 males (aged 13-20 yrs; PST T3-T5) and 52 females (aged 13-18 yrs; PST T2-T4; all but three had already undergone menarche). In male adolescents, height, weight, TVI, lung volumes and TL,CO increased with age. This was not the case in female adolescents. In males, the TVI was the independent variable that best correlated with pulmonary volumes. In females, height was the independent variable that best correlated with pulmonary volumes. In both sexes, the variable that best correlated with TL,CO was PST, associated with height in males. This cross-sectional study provides prediction equations for lung volumes and the lung transfer factor for carbon monoxide taking into account thoracic volume index and pubertal stage. It shows that, in adolescent males, lung and thoracic development occurs during and until the end of puberty. Conversely, in adolescent females, lung development is almost finished following menarche.

Adolescent↗
PubMed2002

Consensus statements from the Second International Lung Cancer Molecular Biomarkers Workshop: a European strategy for developing lung cancer molecular diagnostics in high risk populations.

The Second Molecular Biomarkers Workshop was held at the Roy Castle International Centre for Lung Cancer Research in Liverpool, in June 2001 and it brought together experts in the clinical, epidemiological and molecular-pathology of lung cancer from Europe and the USA, to address issues surrounding the development of a European strategy for early lung cancer detection. The 2001 Workshop Breakout Groups concentrated on the current challenges in the early detection of lung cancer which need to be addressed in the light of the recent surge in interest in many countries for mounting new clinical trials to evaluate the utility of Spiral CT in early lung cancer detection. If population-based trials of CT screening are mounted it will also be a favorable clinical environment in which to evaluate efficiently recent advances in molecular screening and genotyping. The Workshop focused specifically on: a) clinical and molecular biomarkers, b) sputum as an early detection and diagnostic tool, c) validation of molecular markers prior to their use in early detection trials and d) ethical issues that have to be considered in early lung cancer detection trials. A distillation of the Workshop discussions is given in this article.

Biomarkers, Tumor↗
PubMed2002

[Dermatology in private practice in France in 2000].

OBJECTIVES: Data regarding French dermatological practice are scarce. Our objective was to identify the skin disorders most commonly diagnosed by office-based dermatologists. We also documented the severity of these skin disorders, as reflected by the repercussions on patient's everyday life, and the way physicians managed patients. DESIGN: We carried out a one-day survey of visits to a randomly selected sample of 900 French office-based dermatologists. The randomization was stratified according to the five French different dialing area codes. RESULTS: Office-based dermatologists saw 6411 patients with 7839 skin disorders during the survey. The daily number of visits to French dermatologists was estimated at 47 000 and the annual number between 12 and 14 millions. Office-based dermatologists mostly managed warts, acne, nevus, dermatitis, malignancies and pre-malignancies, fungal infection and psoriasis. Repercussions on patients'everyday life were assessed by physicians as important or very important in 28 p. 100 of cases. Half of the patients received topical treatment, 20.5 p. 100 a systemic drug and 40 p. 100 a minor surgical procedure (including cryotherapy). CONCLUSION: Although dermatologists frequently see benign skin disorders such as warts or nevus, more severe diseases represent an important part of their activity.

Dermatology↗
PubMed2002

[DEPISCAN--a pilot study to evaluate low dose spiral CT scanning as a screening method for bronchial carcinoma].

The outcome of collaboration between INSERM (National Institute for Health and Medical Research), SFR (French Radiological Society) and SPLF (French Language Society of Pneumology), DEPISCAN is a pilot study for a large randomised trial which aims to evaluate screening for broncho-pulmonary cancer by the low dose spiral CT scanner. The principal objective of this preliminary study is to test the feasibility of a randomised study comparing the CT scanner and the chest x-ray in 1,000 smokers and ex-smokers aged over 50 and followed up for 2 years. Recruitment of subjects will be undertaken by 130 general practitioners based on 14 hospital centres distributed throughout France. We will evaluate the safety of the patients and the effect of screening on their quality of life and their tobacco consumption as well as the economic and methodological aspects of the study.

Aged↗
PubMed2001

Severe perturbations of the blood T cell repertoire in polymyositis, but not dermatomyositis patients.

Polymyositis and dermatomyositis are diseases characterized by muscle weakness and muscle inflammatory infiltrates. Their pathogenesis remains unclear. A central role for endomysial autoaggressive CD8(+) T cells is suspected in polymyositis and for perivascular B cells in dermatomyositis. We compared the T cell repertoire of 10 polymyositis and 10 dermatomyositis patients by immunoscope, a method providing a global assessment of the T cell repertoire and a sensitive detection of clonal T cell expansions. Samples were analyzed qualitatively and quantitatively in the blood (unsorted cells and CD4(+) and CD8(+) cells) and in muscle infiltrates. Dramatic perturbations of the T cell repertoire were observed in the blood of polymyositis but not dermatomyositis patients (p < 0.0005), the latter being undistinguishable from controls. These perturbations were due to oligoclonal expansions of CD8(+) T cells and most blood clonal expansions were also found in muscle. These results indicate that the pathogenesis of polymyositis and dermatomyositis is different and reinforce the view that polymyositis but not dermatomyositis is an autoimmune CD8(+) T cell-mediated disease. Moreover, this method may be helpful for the differential diagnosis of polymyositis and dermatomyositis and for noninvasive follow-up of polymyositis patients.

Adult↗
PubMed2001

[Prophylactic prescription of low-molecular-weight heparin in the non-surgical setting: impact of recommendations].

OBJECTIVE: Low-molecular-weight heparins (LMWH) had official approval for use for venous thromboembolism prophylaxis only for surgery patients when this survey was conducted, but were nevertheless often used in non-surgery patients. We conducted this "before and after" survey from May 1998 to April 1999 to assess the impact of the recommendations implemented in the beginning of 1999. METHODS: Data on the use of LMWH were collected on three different days within a three week interval in all non-surgery departments at the Tenon hospital before distribution of expert recommendations early in 1999. Published in La Presse Médicale in January 2000, these recommendations issued from an external panel of 43 experts who were contacted to establish a consensus opinion using the Delphi method. Data were again collected on three different days after implementation of the recommendations. Implementation was based on a patient-specific prescription order form requested by the hospital pharmacy for delivery to the department. RESULTS: Data were collected for 121 prescriptions prior to the recommendations and for 158 after. Sex-ratio, mean age and percentage of LMWH prescriptions did not differ significantly between the two periods. There was a lower number of non-appropriate prescriptions after implementation of the recommendations from 54.5% to 35.4% (p = 0.01) with better conformity for recommendation A (high-risk patients) (36% versus 43%, NS) and for recommendation B (= 2 risk situations or = 1 risk situation and = 2 aggravating factors) (10% versus 22%, p = 0.01). Better conformity of LMWH prescriptions in oncology and radiotherapy departments partially explained this general improvement, but the difference remained significant when excluding these two departments (p = 0.04). CONCLUSION: This study shows that physician compliance with recognized expert recommendations can improve their implementation. This procedure is now in general use in the Tenon hospital.

Aged↗
PubMed2001

Comparison of the statistical efficiency of case-crossover and case-control designs: application to severe cutaneous adverse reactions.

Although case-crossover analyses have lately emerged as an alternative to case-control analyses in epidemiological studies, it is not yet known in which situations they give reliable conclusions. In this work, the case-crossover and the case-control designs were first compared on the basis of a dataset from a published study of severe cutaneous adverse reactions resulting from drug exposures of various durations and prevalences of use (245 cases, 1147 controls, and exposures to 23 drug classes). Next, the statistical efficiency of each design was compared via Monte Carlo simulations. Eight of the 13 risk factors identified by case-control analysis of the published data were also identified by the case-crossover analysis, with fairly good agreement on ranks of risk estimates (Spearman's correlation coefficient = 0.71, P < 0.001 ). Simulation studies showed that for relative risks below 8, the case-crossover design (250 cases, 4 control periods/case) had a higher power than the case-control design (250 cases, 4 controls/case), and that the case-crossover design was more conservative than the case-control design for prevalences of drug use below 10%. We conclude that the case-crossover design is not suitable for long-term exposures, but is an appropriate alternative for assessing rare risks associated with transient to short-term exposures.

Case-Control Studies↗
PubMed2001

The control chart: an epidemiological tool for public health monitoring.

The objective of the authors is to apply the control chart, a statistical method for quality control used in industry, to public health surveillance. A pilot study was conducted during the 1998 World Football Cup (WFC) by 553 sentinel general practitioners (GPs) throughout France. The average number of cases of communicable, environmental and societal diseases relating to mass gatherings, and the total number of referrals to hospital reported daily by a GP, were plotted on a u-chart for each condition monitored. This average was beyond the statistical control limits if it fell outside the 99.7% confidence interval of the baseline incidences estimated before the WFC. Seven hundred and forty data points representing 262 279 medical encounters were plotted. Nineteen points exceeded the statistical control limits. None of these alerts was confirmed for two consecutive days. Control charts ensured that the level of the items chosen for general community health surveillance remained under control.

Anniversaries and Special Events↗
PubMed2001

Postdischarge nosocomial infections in primary care.

OBJECTIVE: To study both surgical and nonsurgical nosocomial infections (NIs) seen by primary-care physicians (general practitioners [GPs]) in France. DESIGN: Ongoing surveillance of postdischarge NIs by an organized group of GPs, from August 1997 to July 1999. Both the GP who personally examined the case spontaneously presenting with NI and the responsible hospital physician or surgeon were interviewed by telephone. SETTING: 305 general practices from all French regions. RESULTS: 2,199 (29%) of 7,540 patients referred for hospitalization reconsulted the GP within 30 days of discharge. In 21 (1%) of the 2,199 cases, an NI was diagnosed by the GP and confirmed as plausible by the responsible hospital physician. We diagnosed an NI in 8 (1.3%) of the post-surgical patients and in 13 (0.8%) of the non-surgical cases within the cohort. We saw eight urinary tract infections, seven surgical-site infections, three soft-tissue infections, two respiratory tract infections, and one primary bloodstream infection. In 19 patients (90%), clinical signs of NI appeared within 7 days of discharge. Assuming that all 5,431 patients who were missed for follow-up did not experience any NI, an attack rate of 0.3 per 100 admissions may be estimated for the whole group. CONCLUSION: We diagnosed 1% of NIs following discharge from a hospital in a cohort of 2,199 patients, of which 1.3% were seen post-surgery and 0.8% following nonsurgical admissions. The percentage of postdischarge visits that were for an NI in nonsurgical patients warrants a major effort with feedback to the hospital physician to reduce infection rates.

Aftercare↗
PubMed2001

Clinical evaluation of circulating blood volume in critically ill patients--contribution of a clinical scoring system.

The circulating blood volume (CBV) of critically ill patients may be difficult to estimate on the basis of history and physical examination. The aim of this study was to evaluate the ability of seven clinical signs and central venous pressure (CVP) to predict CBV in critically ill patients; CBV was evaluated with the [125I]human serum albumin technique. A scoring system was constructed using a combination of independence Bayes method and logistic regression. Sixty-eight patients constituted a 'model development' sample and 30 patients a validation sample. Thirty-six patients (53%) in the model development sample were found to have a low CBV (measured CBV at least 10% lower than the predicted mean normal CBV). Neither the haemodynamic variables monitored in ICU, nor the spot urinary sodium concentrations were different between patients with and without a low CBV. Individually, none of the clinical signs tested have a good positive or negative predictive value. For CVP, only extreme values seem to have clinical significance. To construct the score, the signs tested were ranked according to their discriminating efficacy. The probability of a low CBV was obtained by adding the weights of each sign tested and converting the score obtained into a probability. On a validation sample of 30 patients, the predictions are reliable as assessed by Z statistics ranging between -2 and +2. Our results suggest that: (1) individually, no clinical sign presented a clinical useful predictive value; and (2) a clinical scoring system may be helpful for the evaluation of CBV in critically ill patients.

Adult↗
PubMed2001

AIDS-related alveolar hemorrhage: a prospective study of 273 BAL procedures.

STUDY OBJECTIVES: To evaluate the frequency and diagnostic significance of alveolar hemorrhage (AH) in HIV-infected patients. DESIGN: A 3-year prospective cohort study. SETTING: A university hospital in Paris, France. PATIENTS: Two hundred forty-three HIV-infected patients undergoing 273 BAL procedures during the study period. METHODS: AH was assessed by using the Golde score. Data on the patients treated and observed in our institution were collected, as well as on their survival rate 12 months after undergoing BAL. Risk factors for AH were sought by comparing patients with AH (cases) and those without AH (control subjects). RESULTS: AH frequently occurred but usually was subclinical and cytologically mild. AH did not alter the 12-month survival rate. AH always was associated with at least one specific AIDS-related pulmonary disorder, and the following four independent risk factors were identified in a stepwise forward logistic regression model: pulmonary Kaposi's sarcoma (KS; odds ratio [OR], 5.3; 95% confidence interval [CI], 1.8 to 16.7; p = 0.003), cytomegalovirus (CMV) pneumonia (OR, 9.8; 95% CI, 1 to 100; p = 0.05), hydrostatic pulmonary edema (OR, 16.4; 95% CI, 1.8 to 142; p = 0.01), and platelet count < 60,000 cells/microL (OR, 5.6; 95% CI, 1.5 to 20; p = 0.009). CONCLUSIONS: AH is frequently diagnosed during BAL in HIV-infected patients. Its presence may point to an underlying cause, such as pulmonary KS, CMV pneumonia, or hydrostatic pulmonary edema, or to triggering factors such as thrombocytopenia.

AIDS-Related Opportunistic Infections↗
PubMed2001

Postdischarge adverse drug reactions in primary care originating from hospital care in France: a nationwide prospective study.

OBJECTIVE: To describe and estimate the incidence and preventability of postdischarge adverse drug reactions (ADRs) detected in primary care in France. DESIGN: Prospective study of patients referred to hospital by participating general practitioners (GPs). These GPs reported all cases of an adverse reaction to a drug instituted in hospital among patients who consulted them within 30 days of discharge. SETTING: 305 general practices from all French regions. PATIENTS: 7540 patients referred by GPs to private or public hospitals. MAIN OUTCOME MEASURES: The incidence for postdischarge ADRs in primary care, and their preventability. RESULTS: 30 cases of postdischarge ADR were detected in 29 re-consulting patients, yielding a minimal incidence for France of 0.4 per 100 admissions (95% confidence interval 0.3 to 0.6). The ADRs were assessed as serious in 60% of cases. The main drug classes implicated were cardiovascular drugs (8 ADRs), oral anticoagulants (6), psychoactive drugs (4), antidiabetics (3), and opioid analgesics (3). Patients experiencing a postdischarge ADR were older than patients not experiencing one (median age: 77 vs 68 years; p = 0.004). Detected ADRs were considered preventable in 59% of cases. CONCLUSIONS: Physicians and patients should be aware of the possible occurrence of postdischarge ADRs. Patient information in hospital, close postdischarge follow-up of patients at risk, and appropriate transmission of information between hospital physicians and GPs can help to prevent them.

Adolescent↗
PubMed2001

Sentinel monitoring of general community health during the 1998 World Football Cup.

BACKGROUND: Present knowledge of the consequences of mass gatherings for the health of the community is scant. Our objective was to determine the impact of the 1998 World Football Cup on general community health. METHODS: We set up an electronic sentinel disease surveillance, before, during and after the World Football Cup tournament held in France from June 10 to July 12, 1998. Medical activity, and the daily number of cases of communicable, environmental, and societal diseases relating to mass gatherings were surveyed. The incidence of the pathologies surveyed in real time during and after the World Cup versus the pre-Cup reference period was the main outcome measure. Five sentinel networks participated, comprising 553 general practitioners, 60 hospital adult emergency departments, 19 private emergency community services, 4 community health centres, and the medical centre of the Paris airports. RESULTS: Throughout the 66-day study period, physicians reported 558,829 medical encounters via 21,532 connections to the computer. Compared to the reference period, the level of medical activity reflected by the pathological items surveyed remained stable during the study period. CONCLUSION: The 1998 World Football Cup had no epidemiological impact on general community health, as observed by sentinel networks located downstream of the specific health services provided by the French authorities to ensure high standards of safety.

Adult↗