Jean-François Viel

Prof. Jean-François Viel


Research Focus & Metrics

Academic Career Length

43Years (1984-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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5 March 2012 in PLOS ONE
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Journal Article
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MTMichel Tiv
Michel Tiv
JVJean-François Viel
Jean-François Viel
FMFrédéric Mauny
Frédéric Mauny
EEEveline Eschwège
Eveline Eschwège
AWAlain Weill
Alain Weill
APAlfred Penfornis
Alfred Penfornis
Adherence to prescribed medications is a key dimension of healthcare quality. The aim of this large population-based study was to evaluate self-reported medication adherence and to identify factors linked with poor adherence in patients with type 2 diabetes in France. The ENTRED study 2007, a French national survey of people treated for diabetes, was based on a representative sample of patients who claimed reimbursement for oral hypoglycaemic agents and/or insulin at least three times between August 2006 and July 2007, and who were randomly selected from the database of the two main National Health Insurance Systems. Medication adherence was determined using a six-item self-administered questionnaire. A multinomial polychotomous logistic regression model was used to identify factors associated with medication adherence in the 3,637 persons with type 2 diabetes. Thirty nine percent of patients reported good medication adherence, 49% medium adherence and 12% poor adherence. The factors significantly associated with poor adherence in multivariate analysis were socio-demographic factors: age 8% and existing diabetes complications; and health care-related factors: difficulties for taking medication alone, decision making by the patient only, poor acceptability of medical recommendations, lack of family or social support, need for information on treatment, reporting no confidence in the future, need for medical support and follow-up by a specialist physician. In a country with a high level of access to healthcare, our study demonstrated a substantial low level of medication adherence in type 2 diabetic patients. Better identification of those with poor adherence and individualised suitable recommendations remain essential for better healthcare management.

1 September 2015 in Environment International
Verified
Journal Article
Closed access
JVJean-François Viel
Jean-François Viel
CWCharline Warembourg
Charline Warembourg
GMGaïd Le Maner-Idrissi
Gaïd Le Maner-Idrissi
ALAgnès Lacroix
Agnès Lacroix
GLGwendolina Limon
Gwendolina Limon
CCCécile Chevrier
Cécile Chevrier

1 August 1996 in Neurology
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TMT. Moulin
T. Moulin
FCF. Cattin
F. Cattin
TCT. Crepin-Leblond
T. Crepin-Leblond
LTL. Tatu
L. Tatu
DCD. Chavot
D. Chavot
JBJ. F. Bonneville
J. F. Bonneville
During the first hours after acute ischemic stroke, the CT usually shows no abnormalities.Therapeutic trials of ischemia in the middle cerebral artery (MCA) territory involves decision-making when the CT may not show obvious ischemic changes. We reviewed 100 consecutive patients, admitted within 14 hours after a first stroke. Selective criteria were clinical presentation with MCA ischemia and at least two CTs (1 initial and 1 control). All CTs were retrospectively analyzed by at least two physicians blinded to the patient9s status. On the first CT, early signs were hyperdense MCA sign (HMCAS), early parenchymatous signs (attenuation of the lentiform nucleus [ALN], loss of the insular ribbon [LIR], and hemispheric sulcus effacement [HSE]), midline shift, and early infarction. Subsequent infarct locations were classified according to total, partial superficial (superior or inferior), deep, or multiple MCA territories. Clinical features, etiology, and Rankin scale were collected. There were 52 women (mean age 70.8). The CTs were performed at mean 6.4 hours (1 to 14 hours) and before the sixth hour in 62% of the patients. Early CT was abnormal in 94% of the cases, and the abnormalities found were an HMCAS in 22 patients, ALN in 48, LIR in 59, HSE in 69, midline shift in 5, and early infarct in 7. CT was normal in six patients where it was performed earliest (mean 4.5 hours) and in the oldest patients (mean age 80.1). Early parenchymatous CT signs were significantly associated with subsequent MCA infarct location and extension: ALN and deep infarct, HSE and superficial infarct, LIR and large infarct. HMCAS was never found in isolation and was always associated with the three other signs in extended MCA infarct. The presence of two or three signs (ALN, LIR, or HSE) was associated with extended MCA infarct (p < 0.001) and poor outcome (p < 0.001). Our findings suggest that CT frequently discloses parenchymal abnormalities during the first hours of ischemic stroke. Early signs allow the prediction of subsequent infarct locations; CT may provide a simple tool in evaluating the early prognosis of MCA infarction and thus may be useful in selecting better treatments. NEUROLOGY 1996;47: 366-375

13 September 2012 in International Journal of Health Geographics
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Journal Article
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CBCamille Buscail
Camille Buscail
EUErika Upegui
Erika Upegui
JVJean-François Viel
Jean-François Viel
Background: Climate change poses unprecedented challenges, ranging from global and local policy challenges to personal and social action. Heat-related deaths are largely preventable, but interventions for the most vulnerable populations need improvement. Therefore, the prior identification of high risk areas at the community level is required to better inform planning and prevention. We aimed to demonstrate a simple and flexible conceptual framework relying upon satellite thermal data and other digital data with the goal of easily reproducing this framework in a variety of urban configurations. Results: The study area encompasses Rennes, a medium-sized French city. A Landsat ETM + image (60 m resolution) acquired during a localized heatwave (June 2001) was used to estimate land surface temperature (LST) and derive a hazard index. A land-use regression model was performed to predict the LST. Vulnerability was assessed through census data describing four dimensions (socio-economic status, extreme age, population density and building obsolescence). Then, hazard and vulnerability indices were combined to deliver a heatwave health risk index. The LST patterns were quite heterogeneous, reflecting the land cover mosaic inside the city boundary, with hotspots of elevated temperature mainly observed in the city center. A spatial error regression model was highly predictive of the spatial variation in the LST (R 2 = 0.87) and was parsimonious. Three land cover descriptors (NDVI, vegetation and water fractions) were negatively linked with the LST. A sensitivity analysis (based on an image acquired on July 2000) yielded similar results. Southern areas exhibited the most vulnerability, although some pockets of higher vulnerability were observed northeast and west of the city. The heatwave health risk map showed evidence of infra-city spatial clustering, with the highest risks observed in a north–south central band. Another sensitivity analysis gave a very high correlation between 2000 and 2001 risk indices (r = 0.98, p < 10-12). Conclusions: Building on previous work, we developed a reproducible method that can provide guidance for local planners in developing more efficient climate impact adaptations. We recommend, however, using the health risk index together with hazard and vulnerability indices to implement tailored programs because exposure to heat and vulnerability do not require the same prevention strategies.

1 July 2000 in American Journal of Epidemiology
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Journal Article
Open access
JVJean-François Viel
Jean-François Viel
PAPatrick Arveux
Patrick Arveux
JBJosette Baverel
Josette Baverel
JCJean-Yves Cahn
Jean-Yves Cahn
Overall evidence from epidemiologic studies in the workplace suggests that dioxin is a human carcinogen, but whether low doses affect the general population remains to be determined. The authors examined the spatial distribution of soft-tissue sarcomas and non-Hodgkin's lymphomas around a French municipal solid waste incinerator with high emission levels of dioxin (16.3 ng international toxic equivalency factor/m3). Not consistently associated with dioxin exposure, Hodgkin's disease served as the control cancer category. Clusters were identified from 1980 to 1995 in the area (“département”) of Doubs by applying a spatial scan statistic to 26 electoral wards. The most likely and highly significant clusters found were identical for soft-tissue sarcomas and non-Hodgkin's lymphomas and included the area around the municipal solid waste incinerator; standardized incidence ratios were 1.44 (observed number of cases = 45, focused test p value = 0.004) and 1.27 (observed number of cases = 286, focused test p value = 0.00003), respectively. Conversely, Hodgkin's disease exhibited no specific spatial distribution. Confounding by socioeconomic status, urbanization, or patterns of medical referral seemed unlikely to explain the clusters. Although consistent, these findings should be confirmed by further investigation (e.g., a case-control study in which dioxins are measured in biologic tissues) before clusters of soft-tissue sarcoma and non-Hodgkin's lymphoma are ascribed to dioxin released by the municipal solid waste incinerator.