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Risk factors for adverse prognosis and death in American visceral leishmaniasis: a meta-analysis.

Belo VS, Struchiner CJ, Barbosa DS, Nascimento BW, Horta MA, da Silva ES, Werneck GL - PLoS Negl Trop Dis (2014)

Bottom Line: Variables were grouped according to the strength of evidence considering summary measures, patterns and heterogeneity of effect-sizes, and the results of multivariate analyses.Edema and low hemoglobin concentration were also associated with unfavorable outcomes.Integration of the results from different investigations conducted over the last 10 years enabled the identification of consistent prognostic variables that could be useful in recognizing and handling VL patients at higher risk of unfavorable outcomes.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Endemias Samuel Pessoa, Escola Nacional de Saúde Pública Sergio Arouca, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brasil; Departamento Básico-Área da Saúde-Campus Governador Valadares, Universidade Federal de Juiz de Fora, Governador Valadares, Minas Gerais, Brasil.

ABSTRACT

Background: In the current context of high fatality rates associated with American visceral leishmaniasis (VL), the appropriate use of prognostic factors to identify patients at higher risk of unfavorable outcomes represents a potential tool for clinical practice. This systematic review brings together information reported in studies conducted in Latin America, on the potential predictors of adverse prognosis (continued evolution of the initial clinical conditions of the patient despite the implementation of treatment, independent of the occurrence of death) and death from VL. The limitations of the existing knowledge, the advances achieved and the approaches to be used in future research are presented.

Methods/principal findings: The full texts of 14 studies conforming to the inclusion criteria were analyzed and their methodological quality examined by means of a tool developed in the light of current research tools. Information regarding prognostic variables was synthesized using meta-analysis. Variables were grouped according to the strength of evidence considering summary measures, patterns and heterogeneity of effect-sizes, and the results of multivariate analyses. The strongest predictors identified in this review were jaundice, thrombocytopenia, hemorrhage, HIV coinfection, diarrhea, age <5 and age >40-50 years, severe neutropenia, dyspnoea and bacterial infections. Edema and low hemoglobin concentration were also associated with unfavorable outcomes. The main limitation identified was the absence of validation procedures for the few prognostic models developed so far.

Conclusions/significance: Integration of the results from different investigations conducted over the last 10 years enabled the identification of consistent prognostic variables that could be useful in recognizing and handling VL patients at higher risk of unfavorable outcomes. The development of externally validated prognostic models must be prioritized in future investigations.

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Related in: MedlinePlus

Assessment of the adequacy of the methodology employed and the clarity of presentation of the results described in the selected studies determined according to the conditions presented in the Figure 2 Legend: article described and adequately complied with the condition (two positive symbols), article did not refer to the procedure condition (two negative symbols), and article referred to the procedure but did not fully comply with the condition (a negative and a positive symbol).
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pntd-0002982-g004: Assessment of the adequacy of the methodology employed and the clarity of presentation of the results described in the selected studies determined according to the conditions presented in the Figure 2 Legend: article described and adequately complied with the condition (two positive symbols), article did not refer to the procedure condition (two negative symbols), and article referred to the procedure but did not fully comply with the condition (a negative and a positive symbol).

Mentions: Each of the 14 studies reviewed employed appropriate criteria for selecting the study populations and defining the cases, and all except one [36] observed fully the premises for the statistical analysis of the data. Only two studies [27], [29] failed to employ any control for confounding factors and to describe the treatment adopted (which was always based on the recommendations of Brazilian Ministry of Health [12]), although a number of studies presented limitations regarding the definitions of variables [27], [31], [33], [36], [37], extraction of data from medical records [11], [27], [33], [34], [36], [37], selection of variables for the regression models [27], [29], [32], [36], [37], and description of the results [11], [27], [33], [36], [37]. Eight articles failed to provide information regarding missing data in the medical records/SINAN or sample losses [11], [27], [29], [30], [34], [36]–[38] and three [18], [32], [35] of the six studies that described these aspects did not treat the matter in the correct manner. Only one study [32] employed adequate criteria for the stratification of continuous variables. The statistical power was generally low and the treatment of data and the description of the methods employed for the construction of models were poorly described in most articles. For example, testing of interaction effects was described in only one study [18], while multicollinearity testing was fully described in just two studies [28], [38]. Additionally, more than half of the studies (9/14) ignored completely calibration and discrimination procedures [27], [29], [31], [33]–[38]. None of the studies addressed the issue of validation of the predictive regression models in populations other than that of the original study (Fig. 4).


Risk factors for adverse prognosis and death in American visceral leishmaniasis: a meta-analysis.

Belo VS, Struchiner CJ, Barbosa DS, Nascimento BW, Horta MA, da Silva ES, Werneck GL - PLoS Negl Trop Dis (2014)

Assessment of the adequacy of the methodology employed and the clarity of presentation of the results described in the selected studies determined according to the conditions presented in the Figure 2 Legend: article described and adequately complied with the condition (two positive symbols), article did not refer to the procedure condition (two negative symbols), and article referred to the procedure but did not fully comply with the condition (a negative and a positive symbol).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4109848&req=5

pntd-0002982-g004: Assessment of the adequacy of the methodology employed and the clarity of presentation of the results described in the selected studies determined according to the conditions presented in the Figure 2 Legend: article described and adequately complied with the condition (two positive symbols), article did not refer to the procedure condition (two negative symbols), and article referred to the procedure but did not fully comply with the condition (a negative and a positive symbol).
Mentions: Each of the 14 studies reviewed employed appropriate criteria for selecting the study populations and defining the cases, and all except one [36] observed fully the premises for the statistical analysis of the data. Only two studies [27], [29] failed to employ any control for confounding factors and to describe the treatment adopted (which was always based on the recommendations of Brazilian Ministry of Health [12]), although a number of studies presented limitations regarding the definitions of variables [27], [31], [33], [36], [37], extraction of data from medical records [11], [27], [33], [34], [36], [37], selection of variables for the regression models [27], [29], [32], [36], [37], and description of the results [11], [27], [33], [36], [37]. Eight articles failed to provide information regarding missing data in the medical records/SINAN or sample losses [11], [27], [29], [30], [34], [36]–[38] and three [18], [32], [35] of the six studies that described these aspects did not treat the matter in the correct manner. Only one study [32] employed adequate criteria for the stratification of continuous variables. The statistical power was generally low and the treatment of data and the description of the methods employed for the construction of models were poorly described in most articles. For example, testing of interaction effects was described in only one study [18], while multicollinearity testing was fully described in just two studies [28], [38]. Additionally, more than half of the studies (9/14) ignored completely calibration and discrimination procedures [27], [29], [31], [33]–[38]. None of the studies addressed the issue of validation of the predictive regression models in populations other than that of the original study (Fig. 4).

Bottom Line: Variables were grouped according to the strength of evidence considering summary measures, patterns and heterogeneity of effect-sizes, and the results of multivariate analyses.Edema and low hemoglobin concentration were also associated with unfavorable outcomes.Integration of the results from different investigations conducted over the last 10 years enabled the identification of consistent prognostic variables that could be useful in recognizing and handling VL patients at higher risk of unfavorable outcomes.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Endemias Samuel Pessoa, Escola Nacional de Saúde Pública Sergio Arouca, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brasil; Departamento Básico-Área da Saúde-Campus Governador Valadares, Universidade Federal de Juiz de Fora, Governador Valadares, Minas Gerais, Brasil.

ABSTRACT

Background: In the current context of high fatality rates associated with American visceral leishmaniasis (VL), the appropriate use of prognostic factors to identify patients at higher risk of unfavorable outcomes represents a potential tool for clinical practice. This systematic review brings together information reported in studies conducted in Latin America, on the potential predictors of adverse prognosis (continued evolution of the initial clinical conditions of the patient despite the implementation of treatment, independent of the occurrence of death) and death from VL. The limitations of the existing knowledge, the advances achieved and the approaches to be used in future research are presented.

Methods/principal findings: The full texts of 14 studies conforming to the inclusion criteria were analyzed and their methodological quality examined by means of a tool developed in the light of current research tools. Information regarding prognostic variables was synthesized using meta-analysis. Variables were grouped according to the strength of evidence considering summary measures, patterns and heterogeneity of effect-sizes, and the results of multivariate analyses. The strongest predictors identified in this review were jaundice, thrombocytopenia, hemorrhage, HIV coinfection, diarrhea, age <5 and age >40-50 years, severe neutropenia, dyspnoea and bacterial infections. Edema and low hemoglobin concentration were also associated with unfavorable outcomes. The main limitation identified was the absence of validation procedures for the few prognostic models developed so far.

Conclusions/significance: Integration of the results from different investigations conducted over the last 10 years enabled the identification of consistent prognostic variables that could be useful in recognizing and handling VL patients at higher risk of unfavorable outcomes. The development of externally validated prognostic models must be prioritized in future investigations.

Show MeSH
Related in: MedlinePlus