118 research outputs found
Beliefs and Risk Perceptions About COVID-19: Evidence From Two Successive French Representative Surveys During Lockdown
Background: The outbreak of COVID-19 has been a major interrupting event, challenging how societies and individuals deal with risk. An essential determinant of the virus’ spread is a series of individual decisions, such as wearing face masks in public space. Those decisions depend on trade-offs between costs (or benefits) and risks, and beliefs are key to explain these.
Methods: We elicit beliefs about the COVID-19 pandemic during lockdown in France by means of surveys asking French citizens about their belief of the infection fatality ratio (IFR) for COVID-19, own risk to catch the disease, risk as perceived by others, and expected prevalence rate. Those self-assessments were measured twice during lockdown: about 2 weeks after lockdown started and about 2 weeks before lockdown ended. We also measured the quality of these beliefs with respect to available evidence at the time of the surveys, allowing us to assess the calibration of beliefs based on risk-related socio-demographics. Finally, comparing own risk to expected prevalence rates in the two successive surveys provides a dynamic view of comparative optimism with respect to the disease.
Results: The risk perceptions are rather high in absolute terms and they increased between the two surveys. We found no evidence for an impact of personal experience with COVID-19 on beliefs and lower risk perceptions of the IFR when someone in the respondent’s family has been diagnosed with a disease. Answers to survey 1 confirmed this pattern with a clear indication that respondents were optimistic about their chances to catch COVID-19. However, in survey 2, respondents revealed comparative pessimism.
Conclusion: The results show that respondents overestimated the probabilities to catch or die from COVID-19, which is not unusual and does not necessarily reflect a strong deviation from rational behavior. While a rational model explains why the own risk to catch COVID-19 rose between the two surveys, it does not explain why the subjective assessment of the IFR remained stable. The comparative pessimism in survey 2 was likely due to a concomitant increase in the respondents’ perceived chances to catch the disease and a decreased expected prevalence rate
Symptom-based stratification of patients with primary Sjögren's syndrome: multi-dimensional characterisation of international observational cohorts and reanalyses of randomised clinical trials
Background
Heterogeneity is a major obstacle to developing effective treatments for patients with primary Sjögren's syndrome. We aimed to develop a robust method for stratification, exploiting heterogeneity in patient-reported symptoms, and to relate these differences to pathobiology and therapeutic response.
Methods
We did hierarchical cluster analysis using five common symptoms associated with primary Sjögren's syndrome (pain, fatigue, dryness, anxiety, and depression), followed by multinomial logistic regression to identify subgroups in the UK Primary Sjögren's Syndrome Registry (UKPSSR). We assessed clinical and biological differences between these subgroups, including transcriptional differences in peripheral blood. Patients from two independent validation cohorts in Norway and France were used to confirm patient stratification. Data from two phase 3 clinical trials were similarly stratified to assess the differences between subgroups in treatment response to hydroxychloroquine and rituximab.
Findings
In the UKPSSR cohort (n=608), we identified four subgroups: Low symptom burden (LSB), high symptom burden (HSB), dryness dominant with fatigue (DDF), and pain dominant with fatigue (PDF). Significant differences in peripheral blood lymphocyte counts, anti-SSA and anti-SSB antibody positivity, as well as serum IgG, κ-free light chain, β2-microglobulin, and CXCL13 concentrations were observed between these subgroups, along with differentially expressed transcriptomic modules in peripheral blood. Similar findings were observed in the independent validation cohorts (n=396). Reanalysis of trial data stratifying patients into these subgroups suggested a treatment effect with hydroxychloroquine in the HSB subgroup and with rituximab in the DDF subgroup compared with placebo.
Interpretation
Stratification on the basis of patient-reported symptoms of patients with primary Sjögren's syndrome revealed distinct pathobiological endotypes with distinct responses to immunomodulatory treatments. Our data have important implications for clinical management, trial design, and therapeutic development. Similar stratification approaches might be useful for patients with other chronic immune-mediated diseases.
Funding
UK Medical Research Council, British Sjogren's Syndrome Association, French Ministry of Health, Arthritis Research UK, Foundation for Research in Rheumatology
B-cell and T-cell quantification in minor salivary glands in primary Sjögren’s syndrome: development and validation of a pixel-based digital procedure
Value of ultrasonography as a marker of early response to abatacept in patients with rheumatoid arthritis and an inadequate response to methotrexate: results from the APPRAISE study
Objectives: To study the responsiveness of a combined power Doppler and greyscale ultrasound (PDUS) score for assessing synovitis in biologic-naïve patients with rheumatoid arthritis (RA) starting abatacept plus methotrexate (MTX). Methods: In this open-label, multicentre, single-arm study, patients with RA (MTX inadequate responders) received intravenous abatacept (∼10 mg/kg) plus MTX for 24 weeks. A composite PDUS synovitis score, developed by the Outcome Measures in Rheumatology–European League Against Rheumatism (OMERACT–EULAR)-Ultrasound Task Force, was used to evaluate individual joints. The maximal score of each joint was added into a Global OMERACT–EULAR Synovitis Score (GLOESS) for bilateral metacarpophalangeal joints (MCPs) 2–5 (primary objective). The value of GLOESS containing other joint sets was explored, along with clinical efficacy. Results: Eighty-nine patients completed the 24-week treatment period. The earliest PDUS sign of improvement in synovitis was at week 1 (mean change in GLOESS (MCPs 2–5): −0.7 (95% CIs −1.2 to −0.1)), with continuous improvement to week 24. Early improvement was observed in the component scores (power Doppler signal at week 1, synovial hyperplasia at week 2, joint effusion at week 4). Comparable changes were observed for 22 paired joints and minimal joint subsets. Mean Disease Activity Score 28 (C reactive protein) was significantly reduced from weeks 1 to 24, reaching clinical meaningful improvement (change ≥1.2) at week 8. Conclusions: In this first international prospective study, the composite PDUS score is responsive to abatacept. GLOESS demonstrated the rapid onset of action of abatacept, regardless of the number of joints examined. Ultrasound is an objective tool to monitor patients with RA under treatment. Trial registration number: NCT00767325
Irreversible Electroporation: Disappearance of Observable Changes at Imaging Does Not Always Imply Complete Reversibility of the Underlying Causal Tissue Changes
Irreversible Electroporation: Disappearance of Observable Changes at Imaging Does Not Always Imply Complete Reversibility of the Underlying Causal Tissue Change
Numerical modelling challenges for clinical electroporation ablation technique of liver tumors
Electroporation ablation is a promising non surgical and minimally invasive technique of tumor ablation, for which no monitoring is currently available. In this paper, we present the recent advances and challenges on the numerical modeling of clinical electroporation ablation of liver tumors. In particular, we show that a nonlinear static electrical model of tissue combined with clinical imaging can give crucial information of the electric field distribution in the clinical configuration. We conclude the paper by presenting some important questions that have to be addressed for an effective impact of computational modeling in clinical practice of electroporation ablation. Mathematics Subject Classification. 35J15, 35J87, 92B.Initiative d'excellence de l'Université de Bordeau
Responses to increasing cigarette prices in France: How did persistent smokers react?
International audienceObjectives: (1) To build a typology of persistent smokers' reactions to increasing cigarette prices (persistent smokers were defined as smokers who did not quit because of such increases) and (2) to investigate which factors were correlated with their reactions (we considered three categories: no reaction, trying to quit or smoking less, reducing the cost of smoking). Methods: We used a French national telephone survey (n = 2000; 621 smokers) that included questions about smokers' reactions to increasing cigarette prices, as well as questions about their socio-demographic background, personal time perspective, smoking behavior and reasons for smoking. We used logistic regressions to identify which of these factors were linked to smokers' reactions. Results: In response to the increasing cigarette prices, 24% of persistent smokers did not change their smoking habits at all, 31% only reduced the cost of smoking (they neither reduced their consumption nor tried to quit) and 45% tried to give up smoking or reduced their consumption (they also frequently reduced the cost of smoking). Male and older smokers, the more educated ones and the wealthier ones more frequently reported no reaction at all, as did those who smoked to improve their concentration or keep their weight down. Younger and unemployed smokers more frequently opted for spending less on cigarettes, as did those who smoked to forget about their problems. Finally, present-oriented smokers were less prone to try to quit or to reduce their consumption. Conclusion: These findings show the need to increase the price of all tobacco products in cooperation with neighboring states. People's reasons for smoking and their personal time perspectives contribute to their reactions to price increases, and different preventive measures are required for each category of persistent smokers
Time preferences, socioeconomic status and smokers' behaviour, attitudes and risk awareness
International audienceBackground: Tobacco control policies have succeeded in reducing tobacco use, but the negative correlation between smoking prevalence and socioeconomic status (SES) has increased. This study focused on the relationships between time preferences, SES, and smoking behaviour, attitudes and risk awareness. Methods: A cross-sectional telephone survey was conducted in France in 2008 on a representative national sample of people aged 18-75 (N = 2000, including 621 smokers) years. Two scales measuring planning horizon and impulsivity and various indicators of SES were introduced into the logistic regressions performed on smoking status and smokers' attitudes to anti-smoking campaigns, quitting attempts, attempts to quit or smoke less, fear of smoking-related cancer and risk perception. Results: Indicators of lower SES and smoking status were correlated with present time orientation and impulsivity. On modelling smoking status, time orientation and lower SES were found to be significant predictors. Among smokers, lower SES and present time orientation were predictive of smoking-related outcomes: little personal concern with anti-tobacco campaigns, not reporting recent behavioural changes, not expressing personal fear of smoking-related cancer and low risk awareness. When time-related preferences were introduced into the analysis, the effects of several lower SES indicators (especially a low educational level) became non-significant. Conclusion: The relationship between SES and smoking behaviour, attitudes and beliefs may be partly mediated by time preferences. Time preference is strongly correlated with smoking status, risk perceptions and attitudes towards anti-smoking campaigns. Tobacco control policies should include messages targeting present time-oriented smokers and/or interventions designed to enhance more future-oriented attitudes among smokers
Beliefs and Risk Perceptions About COVID-19: Evidence From Two Successive French Representative Surveys During Lockdown
International audienceBackground The outbreak of COVID-19 has been a major interrupting event, challenging how societies and individuals deal with risk. An essential determinant of the virus’ spread is a series of individual decisions, such as wearing face masks in public space. Those decisions depend on trade-offs between costs (or benefits) and risks, and beliefs are key to explain these. Methods We elicit beliefs about the COVID-19 pandemic during lockdown in France by means of surveys asking French citizens about their belief of the infection fatality ratio (IFR) for COVID-19, own risk to catch the disease, risk as perceived by others, and expected prevalence rate. Those self-assessments were measured twice during lockdown: about 2 weeks after lockdown started and about 2 weeks before lockdown ended. We also measured the quality of these beliefs with respect to available evidence at the time of the surveys, allowing us to assess the calibration of beliefs based on risk-related socio-demographics. Finally, comparing own risk to expected prevalence rates in the two successive surveys provides a dynamic view of comparative optimism with respect to the disease. Results The risk perceptions are rather high in absolute terms and they increased between the two surveys. We found no evidence for an impact of personal experience with COVID-19 on beliefs and lower risk perceptions of the IFR when someone in the respondent’s family has been diagnosed with a disease. Answers to survey 1 confirmed this pattern with a clear indication that respondents were optimistic about their chances to catch COVID-19. However, in survey 2, respondents revealed comparative pessimism. Conclusion The results show that respondents overestimated the probabilities to catch or die from COVID-19, which is not unusual and does not necessarily reflect a strong deviation from rational behavior. While a rational model explains why the own risk to catch COVID-19 rose between the two surveys, it does not explain why the subjective assessment of the IFR remained stable. The comparative pessimism in survey 2 was likely due to a concomitant increase in the respondents’ perceived chances to catch the disease and a decreased expected prevalence rate
Chapitre V. Comment les Français ont-ils perçu le risque d’infection ?
International audienceDes perceptions cruciales dans un contexte pandémiqueConfrontés à des situations épidémiques de forte incertitude, les individus mobilisent de nombreuses ressources sociales et cognitives pour en évaluer les éventualités et guider leurs comportements. Ce processus d’évaluation est fondamental, puisqu’à titre individuel, nous ne disposons pas, dans les situations d’émergence, d’éléments robustes, clairs et chiffrés sur nos propres probabilités d’être infecté par un virus, de développer une forme grave nécessitant une hospitalisation, voire de décéder
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