96 research outputs found
Early markers of prolonged hospital stay in demented inpatients: A multicentre and prospective study
Background: Dementia is a serious, chronic, and costly public health problem. Prior studies have described dementia as increasing length of hospital stay, but so far no explanations have been proposed. Methods: To identify early markers for prolonged hospital stay in demented elderly inpatients, 178 community-dwelling or institutionalized subjects aged 75+, hospitalized through an emergency department in 9 teaching hospitals in France, were analyzed. Prolonged hospital stays were defined according a limit adjusted for Diagnosis Related Group. All patients underwent a comprehensive geriatric assessment at admission. Logistic regression multifactorial mixed model was performed. Center effect was considered as a random effect. Results: Of the 178 stays, 52 were prolonged. Most concerned community-dwelling patients (86%). Multifactor analysis demonstrated that demographic variables had no influence on the length of stay, while diagnosis of delirium (OR 2.31; 95% CI 1.77-2.91), walking difficulties (OR 1.94; 95% CI 1.62-2.43) and report by the informal caregiver of moderate or severe burden (OR 1.52; 95% CI 1.19-1.86) or low social quality-of-life score (OR 1.25; 95% CI 1.03-1.40), according to the Zarit's Burden Inventory short scale (12 items) and the Duke's Health Profile respectively, were identified as early markers for prolonged hospital stays. Conclusion: At the time of the rising incidence of cognitive disorders, these results suggest that preventive approaches might be possible. In a hospital setting as well as in a community-dwelling population, more specific, specialized and coordinated care, using the expertise of multiple disciplines appears as a probable effective measure to limit prolonged hospital stay. Such approaches require (i) clear patient-oriented goal definition, (ii) understanding and appreciation of roles among various health care and social disciplines and, (iii) cooperation between partners in patient's management. However, the cost- and health-effectiveness of such approaches should be evaluate
Effectiveness of insecticidal nets on uncomplicated clinical malaria : a case-control study for operational evaluation
Background: In a context of large-scale implementation of malaria vector control tools, such as the distribution of long-lasting insecticide nets (LLIN), it is necessary to regularly assess whether strategies are progressing as expected and then evaluate their effectiveness. The present study used the case-control approach to evaluate the effectiveness of LLIN 42 months after national wide distribution. This study design offers an alternative to cohort study and randomized control trial as it permits to avoid many ethical issues inherent to them. Methods: From April to August 2011, a case-control study was conducted in two health districts in Benin; Ouidah-Kpomasse-Tori (OKT) in the south and Djougou-Copargo-Ouake (DCO) in the north. Children aged 0-60 months randomly selected from community were included. Cases were children with a high axillary temperature (>= 37.5 degrees C) or a reported history of fever during the last 48 h with a positive rapid diagnostic test (RDT). Controls were children with neither fever nor signs suggesting malaria with a negative RDT. The necessary sample size was at least 396 cases and 1188 controls from each site. The main exposure variable was "sleeping every night under an LLIN for the 2 weeks before the survey" (SL). The protective effectiveness (PE) of LLIN was calculated as PE = 1 - odds ratio. Results: The declared SL range was low, with 17.0 and 27.5 % in cases and controls in the OKT area, and 44.9 and 56.5 % in cases and controls, in the DCO area, respectively. The declared SL conferred 40.5 % (95 % CI 22.2-54.5 %) and 55.5 % (95 % CI 28.2-72.4 %) protection against uncomplicated malaria in the OKT and the DCO areas, respectively. Significant differences in PE were observed according to the mother's education level. Conclusion: In the context of a mass distribution of LLIN, their use still conferred protection in up to 55 % against the occurrence of clinical malaria cases in children. Social factors, the poor use and the poor condition of an LLIN can be in disfavour with its effectiveness. In areas, where LLIN coverage is assumed to be universal or targeted at high-risk populations, case-control studies should be regularly conducted to monitor the effectiveness of LLIN. The findings will help National Malaria Control Programme and their partners to improve the quality of malaria control according to the particularity of each area or region as far as possible
Specific antibodies to Anopheles gSG6-P1 salivary peptide to assess early childhood exposure to malaria vector bites
Background: The estimates of risk of malaria in early childhood are imprecise given the current entomologic and parasitological tools. Thus, the utility of anti-Anopheles salivary gSG6-P1 peptide antibody responses in measuring exposure to Anopheles bites during early infancy has been assessed. Methods: Anti-gSG6-P1 IgG and IgM levels were evaluated in 133 infants (in Benin) at three (M3), six (M6), nine (M9) and 12 (M12) months of age. Specific IgG levels were also assessed in their respective umbilical cord blood (IUCB) and maternal blood (MPB). Results: At M3, 93.98 and 41.35% of infants had anti-gSG6-P1 IgG and IgM Ab, respectively. Specific median IgG and IgM levels gradually increased between M3 and M6 (p < 0.0001 and p < 0.001), M6-M9 (p < 0.0001 and p = 0.085) and M9-M12 (p = 0.002 and p = 0.03). These levels were positively associated with the Plasmodium falciparum infection intensity (p = 0.006 and 0.003), and inversely with the use of insecticide-treated bed nets (p = 0.003 and 0.3). Levels of specific IgG in the MPB were positively correlated to those in the IUCB (R = 0.73; p < 0.0001) and those at M3 (R = 0.34; p < 0.0001). Conclusion: The exposure level to Anopheles bites, and then the risk of malaria infection, can be evaluated in young infants by assessing anti-gSG6-P1 IgM and IgG responses before and after 6-months of age, respectively. This tool can be useful in epidemiological evaluation and surveillance of malaria risk during the first year of life
Heterologous prime-boost vaccination using an ASO3B-adjuvanted influenza A(H5N1) vaccine in infants and children <3 years of age
Presented in part: Options for the Control of Influenza VIII Conference, Cape Town, South Africa, 5â10 September 2013BACKGROUND: Protecting young children from pandemic influenza should also reduce transmission to susceptible adults, including pregnant women. METHODS: An open study assessed immunogenicity and reactogenicity of a heterologous booster dose of A/turkey/Turkey/1/2005(H5N1)-AS03B (AS03B is an Adjuvant System containing α-tocopherol and squalene in an oil-in-water emulsion [5.93 mg tocopherol]) in infants and children aged 6 to <36 months that was given 6 months following 2-dose primary vaccination with A/Indonesia/05/2005(H5N1)-AS03B. Vaccines contained 1.9 ”g of hemagglutinin antigen and AS03B. Hemagglutinin inhibition (HI) responses, microneutralization titers, and antineuraminidase antibody levels were assessed for 6 months following the booster vaccination. RESULTS: For each age stratum (defined on the basis of the subject's age at first vaccination as 6 to <12 months, 12 to <24 months, and 24 to <36 months) and overall (n=113), European influenza vaccine licensure criteria were fulfilled for responses to A/turkey/Turkey/1/2005(H5N1) 10 days following the booster vaccination. Local pain and fever increased with consecutive doses. Anamnestic immune responses were demonstrated for HI, neutralizing, and antineuraminidase antibodies against vaccine-homologous/heterologous strains. Antibody responses to vaccine-homologous/heterologous strains persisted in all children 6 months following the booster vaccination. CONCLUSIONS: Prevaccination of young children with a clade 2 strain influenza A(H5N1) AS03-adjuvanted vaccine followed by heterologous booster vaccination boosted immune responses to the homologous strain and a related clade, with persistence for at least 6 months. The results support a prime-boost vaccination approach in young children for pandemic influenza preparedness. CLINICAL TRIALS REGISTRATION: NCT01323946.Terry Nolan, Patricia Izurieta, Bee-Wah Lee, Poh Chong Chan, Helen Marshall, Robert Booy, Mamadou Drame, and David W. Vaugh
Rapid cognitive decline, one-year institutional admission and one-year mortality: Analysis of the ability to predict and inter-tool agreement of four validated clinical frailty indexes in the safes cohort
Objectives: To evaluate the predictive ability of four clinical frailty indexes as regards one-year rapid cognitive decline (RCD â defined as the loss of at least 3 points on the MMSE score), and one-year institutional admission (IA) and mortality respectively; and to measure their agreement for identifying groups at risk of these severe outcomes. Design: One-year follow-up and multicentre study of old patients participating in the SAFEs cohort study. Setting: Nine university hospitals in France. Participants: 1,306 patients aged 75 or older (mean age 85±6 years; 65% female) hospitalized in medical divisions through an Emergency department. Measurements: Four frailty indexes (Winograd; Rockwood; Donini; and Schoevaerdts) reflecting the multidimensionality of the frailty concept, using an ordinal scoring system able to discriminate different grades of frailty, and constructed based on the accumulation of identified deficits after comprehensive geriatric assessment conducted during the first week of hospital stay, were used to categorize participants into three different grades of frailty: Gl â not frail; G2 â moderately frail; and G3 â severely frail. Comparisons between groups were performed using Fisher's exact test. Agreement between indexes was evaluated using Cohen's Kappa coefficient. Results: All patients were classified as frail by at least one of the four indexes. The Winograd and Rockwood indexes mainly classified subjects as G2 (85% and 96%), and the Donini and Schoevaerdts indexes mainly as G3 (71% and 67%). Among the SAFEs cohort population, 250, 1047 and 1,306 subjects were eligible for analyses of predictability for RCD, 1-year IA and 1-year mortality respectively. At 1 year, 84 subjects (34%) experienced RCD, 377 (36%) were admitted into an institutional setting, and 445 (34%) had died With the Rockwood index, all subjects who expenenced RCD were classified in G2; and in G2 and G3 when the Donini and Schoevaerdts indexes were used No significant difference was found between frailty grade and RCD, whereas frailty grade was significantly associated with an increased risk of IA and death, whatever the frailty index considered. Agreement between the different indexes of frailty was poor with Kappa coefficients ranging from â0.02 to 0.15. Conclusion: These findings confirm the poor clinimetric properties of these current indexes to measure frailty, underlining the fact that further work is needed to develop a better and more widely-accepted definition of frailty and therefore a better understanding of its pathophysiolog
8. Remote Sensing Of Vegetation Fires And Its Contribution To A Fire Management Information System
In the last decade, research has proven that remote sensing can provide very useful support to fire managers. This chapter provides an overview of the types of information remote sensing can provide to the fire community. First, it considers fire management information needs in the context of a fire management information system. An introduction to remote sensing then precedes a description of fire information obtainable from remote sensing data (such as vegetation status, active fire detection and burned areas assessment). Finally, operational examples in five African countries illustrate the practical use of remotely sensed fire information.
As indicated in previous chapters, fire management usually comprises activities designed to control the frequency, area, intensity or impact of fire. These activities are undertaken in different institutional, economic, social, environmental and geographical contexts, as well as at different scales, from local to national. The range of fire management activities also varies considerably according to the management issues at stake, as well as the available means and capacity to act. Whatever the level, effective fire management requires reliable information upon which to base appropriate decisions and actions. Information will be required at many different stages of this fire management system. To illustrate this, we consider a typical and generic description of a fire management loop , as provided in Figure 8.1. Fire management objectives result from fire related knowledge . For example, they may relate to sound ecological reasons for prescribed burning in a particular land management context, or to frequent, uncontrolled fires threatening valuable natural or human resources. Whatever the issues, appropriate objectives require scientific knowledge (such as fire impact on ecosystems components, such as soil and vegetation), as well as up-to date monitoring information (such as vegetation status, fire locations, land use, socioeconomic context, etc.). Policies, generally at a national and governmental level, provide the official or legal long term framework (e.g. five to ten years) to undertake actions. A proper documentation of different fire issues, and their evolution, will allow their integration into appropriate policies, whether specific to fire management, or complementary to other policies in areas such as forestry, rangeland, biodiversity, land tenure, etc. Strategies are found at all levels of fire management. They provide a shorter-term framework (e.g. one to five years) to prioritise fire management activities. They involve the development of a clear set of objectives and a clear set of activities to achieve these objectives. They may also include research and training inputs required, in order to build capacity and to answer specific questions needed to improve fire management. The chosen strategy will result from a trade-off between priority fire management objectives and the available capacity to act (e.g. institutional framework, budget, staff, etc.), and will lead towards a better allocation of resources for fire management operations to achieve specific objectives. One example in achieving an objective of conserving biotic diversity may be the implementation of a patch-mosaic burning system (Brockett et al., 200 1 ) instead of a prescribed block burning system, based on an assumption that the former should better promote biodiversity in the long-term than the latter (Parr & Brockett, 1999). This strategy requires the implementation of early season fires to reduce the size of later season fires. The knowledge of population movements, new settlements or a coming El Nino season, should help focus the resources usage, as these factors might influence the proportion as well as the locations of area burned. Another strategy may be to prioritise the grading of fire lines earlier than usual based on information on high biomass accumulation. However, whatever the strategies, they need to be based on reliable information
8. Remote Sensing Of Vegetation Fires And Its Contribution To A Fire Management Information System
In the last decade, research has proven that remote sensing can provide very useful support to fire managers. This chapter provides an overview of the types of information remote sensing can provide to the fire community. First, it considers fire management information needs in the context of a fire management information system. An introduction to remote sensing then precedes a description of fire information obtainable from remote sensing data (such as vegetation status, active fire detection and burned areas assessment). Finally, operational examples in five African countries illustrate the practical use of remotely sensed fire information.
As indicated in previous chapters, fire management usually comprises activities designed to control the frequency, area, intensity or impact of fire. These activities are undertaken in different institutional, economic, social, environmental and geographical contexts, as well as at different scales, from local to national. The range of fire management activities also varies considerably according to the management issues at stake, as well as the available means and capacity to act. Whatever the level, effective fire management requires reliable information upon which to base appropriate decisions and actions. Information will be required at many different stages of this fire management system. To illustrate this, we consider a typical and generic description of a fire management loop , as provided in Figure 8.1. Fire management objectives result from fire related knowledge . For example, they may relate to sound ecological reasons for prescribed burning in a particular land management context, or to frequent, uncontrolled fires threatening valuable natural or human resources. Whatever the issues, appropriate objectives require scientific knowledge (such as fire impact on ecosystems components, such as soil and vegetation), as well as up-to date monitoring information (such as vegetation status, fire locations, land use, socioeconomic context, etc.). Policies, generally at a national and governmental level, provide the official or legal long term framework (e.g. five to ten years) to undertake actions. A proper documentation of different fire issues, and their evolution, will allow their integration into appropriate policies, whether specific to fire management, or complementary to other policies in areas such as forestry, rangeland, biodiversity, land tenure, etc. Strategies are found at all levels of fire management. They provide a shorter-term framework (e.g. one to five years) to prioritise fire management activities. They involve the development of a clear set of objectives and a clear set of activities to achieve these objectives. They may also include research and training inputs required, in order to build capacity and to answer specific questions needed to improve fire management. The chosen strategy will result from a trade-off between priority fire management objectives and the available capacity to act (e.g. institutional framework, budget, staff, etc.), and will lead towards a better allocation of resources for fire management operations to achieve specific objectives. One example in achieving an objective of conserving biotic diversity may be the implementation of a patch-mosaic burning system (Brockett et al., 200 1 ) instead of a prescribed block burning system, based on an assumption that the former should better promote biodiversity in the long-term than the latter (Parr & Brockett, 1999). This strategy requires the implementation of early season fires to reduce the size of later season fires. The knowledge of population movements, new settlements or a coming El Nino season, should help focus the resources usage, as these factors might influence the proportion as well as the locations of area burned. Another strategy may be to prioritise the grading of fire lines earlier than usual based on information on high biomass accumulation. However, whatever the strategies, they need to be based on reliable information
IgG responses to the gSG6-P1 salivary peptide for evaluating human exposure to Anopheles bites in urban areas of Dakar region, Sénégal
<p>Abstract</p> <p>Background</p> <p>Urban malaria can be a serious public health problem in Africa. Human-landing catches of mosquitoes, a standard entomological method to assess human exposure to malaria vector bites, can lack sensitivity in areas where exposure is low. A simple and highly sensitive tool could be a complementary indicator for evaluating malaria exposure in such epidemiological contexts. The human antibody response to the specific <it>Anopheles </it>gSG6-P1 salivary peptide have been described as an adequate tool biomarker for a reliable assessment of human exposure level to <it>Anopheles </it>bites. The aim of this study was to use this biomarker to evaluate the human exposure to <it>Anopheles </it>mosquito bites in urban settings of Dakar (Senegal), one of the largest cities in West Africa, where <it>Anopheles </it>biting rates and malaria transmission are supposed to be low.</p> <p>Methods</p> <p>One cross-sectional study concerning 1,010 (505 households) children (n = 505) and adults (n = 505) living in 16 districts of downtown Dakar and its suburbs was performed from October to December 2008. The IgG responses to gSG6-P1 peptide have been assessed and compared to entomological data obtained in or near the same district.</p> <p>Results</p> <p>Considerable individual variations in anti-gSG6-P1 IgG levels were observed between and within districts. In spite of this individual heterogeneity, the median level of specific IgG and the percentage of immune responders differed significantly between districts. A positive and significant association was observed between the exposure levels to <it>Anopheles gambiae </it>bites, estimated by classical entomological methods, and the median IgG levels or the percentage of immune responders measuring the contact between human populations and <it>Anopheles </it>mosquitoes. Interestingly, immunological parameters seemed to better discriminate the exposure level to <it>Anopheles </it>bites between different exposure groups of districts.</p> <p>Conclusions</p> <p>Specific human IgG responses to gSG6-P1 peptide biomarker represent, at the population and individual levels, a credible new alternative tool to assess accurately the heterogeneity of exposure level to <it>Anopheles </it>bites and malaria risk in low urban transmission areas. The development of such biomarker tool would be particularly relevant for mapping and monitoring malaria risk and for measuring the efficiency of vector control strategies in these specific settings.</p
Variable selection: current practice in epidemiological studies
Selection of covariates is among the most controversial and difficult tasks in epidemiologic analysis. Correct variable selection addresses the problem of confounding in etiologic research and allows unbiased estimation of probabilities in prognostic studies. The aim of this commentary is to assess how often different variable selection techniques were applied in contemporary epidemiologic analysis. It was of particular interest to see whether modern methods such as shrinkage or penalized regression were used in recent publications. Stepwise selection methods remained the predominant method for variable selection in publications in epidemiological journals in 2008. Shrinkage methods were not used in any of the reviewed articles. Editors, reviewers and authors have insufficiently promoted the new, less controversial approaches of variable selection in the biomedical literature, whereas statisticians may not have adequately addressed the methodâs feasibility
IgG Responses to Anopheles gambiae Salivary Antigen gSG6 Detect Variation in Exposure to Malaria Vectors and Disease Risk
Assessment of exposure to malaria vectors is important to our understanding of spatial and temporal variations in disease transmission and facilitates the targeting and evaluation of control efforts. Recently, an immunogenic Anopheles gambiae salivary protein (gSG6) was identified and proposed as the basis of an immuno-assay determining exposure to Afrotropical malaria vectors. In the present study, IgG responses to gSG6 and 6 malaria antigens (CSP, AMA-1, MSP-1, MSP-3, GLURP R1, and GLURP R2) were compared to Anopheles exposure and malaria incidence in a cohort of children from Korogwe district, Tanzania, an area of moderate and heterogeneous malaria transmission. Anti-gSG6 responses above the threshold for seropositivity were detected in 15% (96/636) of the children, and were positively associated with geographical variations in Anopheles exposure (OR 1.25, CI 1.01â1.54, pâ=â0.04). Additionally, IgG responses to gSG6 in individual children showed a strong positive association with household level mosquito exposure. IgG levels for all antigens except AMA-1 were associated with the frequency of malaria episodes following sampling. gSG6 seropositivity was strongly positively associated with subsequent malaria incidence (test for trend pâ=â0.004), comparable to malaria antigens MSP-1 and GLURP R2. Our results show that the gSG6 assay is sensitive to micro-epidemiological variations in exposure to Anopheles mosquitoes, and provides a correlate of malaria risk that is unrelated to immune protection. While the technique requires further evaluation in a range of malaria endemic settings, our findings suggest that the gSG6 assay may have a role in the evaluation and planning of targeted and preventative anti-malaria interventions
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