abordagem da literatura médica

Abordagem da Literatura Médica

Universidade de Caxias do SulProf. Petrônio Fagundes de Oliveira Fº

[email protected]

http://www.ncbi.nlm.nih.gov/pubmed?term=%22Cort%C3%A9s%20Alvarez%20N%22%5BAuthor%5D

ABORDAGEM DA LITERATURA MÉDICA

http://www.ncbi.nlm.nih.gov/pubmed?term=%22Mart%C3%ADn%20Mateos%20MA%22%5BAuthor%5D

Epidemiologia Clínica

Introdução

• Encontrar a melhor resposta para uma questão clínica é quase como encontrar uma agulha no palheiro.

• As informações essenciais estão misturadas com uma grande quantidade de informações não confiáveis.

• Desafio: separar o joio do trigo!• GESTÃO DO CONHECIMENTO


Qual a informação confiável?


INTERNE

T

CD

DVD


• Embora o objetivo de leitura de publicações científicas possa ser resumido à necessidade de uma constante atualização, entender como a literatura pode ser abordada é fundamental.


• Três tipos de abordagens são possíveis:

1) Leitura de vigilância2) Revisão exaustiva de um tema3) Busca de solução para um problema específico


• Serve para:– Satisfazer a curiosidade científica

do médico acerca das novidades– Adquirir uma cultura biomédica

geral mais ampla e atualizada• Trata-se de uma leitura “corrida” dos

artigos e revistas. ― Triagem de artigos que serão lidos depois com mais

atenção. ― Triagem de artigos que serão lidos depois com mais

atenção• É uma leitura menos comprometida.

Leitura de Vigilância


• A revisão exaustiva é muito mais dirigida.• Geralmente, foca apenas um assunto e deve

abranger, esgotar toda a literatura científica relativa a ele que possa ser encontrada.

• Ela é finita e concentrada no tempo.• Em geral, direciona-se mais para objetivos de

caráter acadêmico.– Monografias, dissertações, teses– Livros

Revisão exaustiva do tema


• É abordagem que mais interessa à maioria dos profissionais, pois resulta diretamente do exercício profissional.

• Decorre dos questionamentos, dúvidas, problemas e doenças trazidos pelos pacientes.

• A leitura deve ser atenta e cuidadosa, pois destina-se a fundamentar cientificamente a solução de um problema clínico.

• É a forma mais comum de aprendizado contínuo - MBE

Busca de solução para um problema específico


• Existem diversas formas de publicações:• Artigos científicos originais• Revisões da literatura• Meta-análises• Capítulos de livros• Livros

Artigos Originais têm maior probabilidade de trazer novidades

Fontes de informação bibliográfica


• Os artigos originais são atraentes, mas requerem mais atenção e cuidado.

• A maioria das novidades não trazem implicações imediatas para a prática profissional.

• As revisões, as metanálises e os livros, em geral, são bastante seguros, mas padecem do fato de chegarem à publicação vários anos após os artigos que lhe deram origem.

• Entretanto, devemos nos lembrar que este envelhecimento pode representar amadurecimento com conclusões mais sólidas.

ARTIGOS ORIGINAIS

O que ler?Como ler?


O que ler?

• De um modo geral deve-se ler as novidades com o objetivo de completar ou atualizar o que o médico deve saber sobre os quatros aspectos básicos da sua atuação profissional:


• O que há de novo quanto a etiologia (ou fatores causais e de risco) de uma doença?

• Qual a validade do que há de novo nos procedimentos diagnósticos (clínicos ou laboratoriais) de uma doença?

• Quais as vantagens , os benefícios e os riscos de um determinado tratamento, novo ou não?

• Quais os atuais perspectivas de evolução e de prognóstico de um determinado paciente?


Como ler?• A estratégia adequada implica em cinco

etapas bem definidas:1) O que é preciso ler?2) Qual a melhor evidência?3) O que vale a pena ler?4) Análise da qualidade do material selecionado

para a leitura.5) Identificação das conclusões que têm

repercussão na prática médica.


1. O que é preciso ler?

• Saber previamente que informação se busca.• Jamais fazer uma busca a esmo.• Antes de iniciar a seleção das leituras é

necessário uma definição do tema a ser abordado e quais as perguntas para as quais se busca resposta.

• As questões devem ser colocadas por escrito, de forma clara, delimitada, bem definida.


ExemploOrigem da busca Tema e Pergunta de busca

• Lactentes sibilantes cujos pais têm asma– Tema de interesse

• Asma Brônquica

– Pergunta a ser respondida

• Qual risco de asma em lactentes sibilantes cujos pais são asmáticos?


P

I

C

O

Lactentes sibilantes filhos de pais asmáticos

Asma no futuro


2. Qual a melhor evidência?• Pesquisa, por exemplo,

no PubMed• Ferramenta de pesquisa

gratuíta mantida pela National Library of Medicine, National Institutes of Health

• Pode ser acessada no endereço: http://www.ncbi.nlm.nih.gov/PubMed/


Medline• Selecionar termos do índice

eletrônico, ou thesaurus. Thesaurus é constituído de MeSH (Medical Subject Headings).

• Pensar nos sinônimos possíveis e nos termos relacionados que possam ser utilizados. Podem ser usados os termos do MeSH ou palavras textuais;

• Combinar os termos, usando operadores lógicos:

• OR, AND, WITH , NEAR• NOT– elimina as palavras

digitas depois do NOT.• ( ) – parênteses são

empregados para agrupar partes da sintaxe, com o objetivo de realizar pesquisas mais complexas


• Na busca, usa-se a língua inglesa, evitando as palavras: about, the, of, a, in, as, if, why, never, before, is e it, pois os mecanismos de busca as ignoram.

• No exemplo anterior:• Buscar com a seguinte

frase : “Risco de asma em lactentes sibilantes” ou, em inglês, “Risk of asthma in young children with recurrent wheezing”. Desta frase, retiram-se as palavras-chave: asthma risk, recurrent wheezing e young children. Busca-se individualmente e depois se combinam as buscas.


Para maiores informações:


3. O que vale a pena ler?

• A partir das questões definidas na primeira etapa temos que selecionar o que vale a pena ler;

• Artigos cuja qualidade vale a pena avaliar, investindo mais tempo na busca das respostas.

• Analisar com cuidado na busca da resposta mais válida que satisfaça a necessidade do paciente que gerou a pergunta de partida.


No exemplo:• Na busca, digitando a palavra asthma risk na janela de

busca do PubMed, limitado aos últimos 10 anos, encontrou-se, em 01/04/2012, 10275 títulos.


No exemplo:• Acrescentando outro limite relacionado às crianças menores

de dois anos de idade e utilizando a outra palavra-chave recurrent wheezing encontrou-se em torno de 111 títulos.


Pediatr Pulmonol. 2010 Feb;45(2):149-56.Prevalence and risk factors of wheeze in Dutch infants in their first year of life.Visser CA, Garcia-Marcos L, Eggink J, Brand PL.SourcePrincess Amalia Children's Clinic, Isala Klinieken, Zwolle, the Netherlands.AbstractFactors operating in the first year of life are critical in determining the onset and persistence of wheezing in preschool children. This study was designed to examine the prevalence and risk factors of wheeze in the first year of life in Dutch infants. This was a population-based survey of 13-month-old infants visiting well baby clinics for a scheduled immunization. Parents/caregivers completed a standardized validated questionnaire on respiratory symptoms in the first year of life and putative risk factors. The independent influence of these factors for wheeze was assessed by multiple logistic regression analysis. A total of 1,115 questionnaires were completed. Wheeze ever (with a prevalence in the first year of life of 28.5%) was independently associated with male gender, eczema, sibs with asthma, any allergic disease in the family, day care, damp housing, and asphyxia. Recurrent wheeze (prevalence 14.5%) showed independent associations with eczema, sibs with asthma, and day care. In addition to these factors, severe wheeze (prevalence 15.4%) was also associated with premature rupture of membranes during birth, and with damp housing. Wheeze is common during the first year of life, and places a major burden on families and the health care system. Factors associated with wheeze are mainly related to markers of atopic susceptibility, and to exposure to infections. The strongest modifiable risk factor for wheeze in the first year of life is home dampness. Interventions to reduce home dampness to reduce wheeze in infancy should be examined.(c) 2010 Wiley-Liss, Inc.


Allergol Immunopathol (Madr). 2007 Nov-Dec;35(6):228-31.Risk factors of developing asthma in children with recurrent wheezing in the first three years of life.Cortés Alvarez N, Martín Mateos MA, Plaza Martín AM, Giner Muñoz MT, Piquer M, Sierra Martínez JI.SourcePaediatric Allergy and Clinical Inmunology Section. Sant Joan de Déu Hospital-Clínic Hospital. University of Barcelona. Spain. [email protected]: Recurrent wheezing is a common problem during the first years of life, but it is still difficult to identify which of these children may develop asthma in the future.OBJECTIVES: To study risk factors of developing asthma in a group of patients with frequent wheezing during the first three years of life.MATERIAL AND METHODS: A prospective study was performed of a group of 60 patients, aged below three, referred to our Hospital for recurrent wheezing. Age, sex, parental and personal history of atopy, clinical features, laboratory tests, evolution and response to treatment were analyzed.RESULTS: 60 patients were enrolled in study. Most of children were boys and have had the first episode of wheezing after the 6 months of life. 63 % had personal history of atopy and 55 % parental history of allergy. The group of atopic children had more wheezing exacerbations and worse evolution than the group of non atopic. They also had more treatment necessities.CONCLUSIONS: The identification of young children at high risk of developing asthma could permit an early intervention before irreversible changes in the airway appeared.


J Pediatr. 2007 Oct;151(4):347-51, 351.e1-2. Epub 2007 Jul 12.Breast-feeding duration and infant atopic manifestations, by maternal allergic status, in the first 2 years of life (KOALA study).Snijders BE, Thijs C, Dagnelie PC, Stelma FF, Mommers M, Kummeling I, Penders J, van Ree R, van den Brandt PA.Source Care and Public Health Research Institute, Maastricht University, Maastricht, The Netherlands. [email protected]: To investigate the potential effect of modification by maternal allergic status on the relationship between breast-feeding duration and infant atopic manifestations in the first 2 years of life.STUDY DESIGN: Data from 2705 infants of the KOALA Birth Cohort Study (The Netherlands) were analyzed. The data were collected by repeated questionnaires at 34 weeks of gestation and 3, 7, 12, and 24 months postpartum. Total and specific immunoglobulin E measurements were performed on venous blood samples collected during home visits at age 2 years. Relationships were analyzed using logistic regression analyses.RESULTS: Longer duration of breast-feeding was associated with a lower risk for eczema in infants of mothers without allergy or asthma (P(trend) = .01) and slightly lower risk in those of mothers with allergy but no asthma (P(trend) = .14). There was no such association for asthmatic mothers (P(trend) = .87). Longer breast-feeding duration decreased the risk of recurrent wheeze independent of maternal allergy (P(trend) = .02) or asthma status (P(trend) = .06).CONCLUSIONS: Our findings show that the relationship between breast-feeding and infant eczema in the first 2 years of life is modified by maternal allergic status. The protective effect of breast-feeding on recurrent wheeze may be associated with protection against respiratory infections.


Pediatrics. 2006 Jun;117(6):e1132-8.

Recurrent wheeze in early childhood and asthma among children at risk for atopy.Ly NP, Gold DR, Weiss ST, Celedón JC.Source Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.AbstractOBJECTIVES: Little is known about the natural history of wheezing disorders among children at risk for atopy. We examined the relation between early wheeze and asthma at 7 years of age among children with parental history of asthma or allergies followed from birth.METHODS: Information on wheeze was collected bimonthly from birth to age 24 months and every 6 months thereafter. Recurrent early wheeze was defined as > or =2 reports of wheezing in the first 3 years of life. Frequent early wheeze was defined as > or =2 reports of wheezing per year in the first 3 years of life. At 7 years of age, asthma was defined as physician-diagnosed asthma and wheezing in the previous year.RESULTS: Of the 440 participating children, 223 (50.7%) had > or =1 report of wheeze before 3 years old, 111 (26.0%) had recurrent early wheeze, and 12 (2.7%) had frequent early wheeze. Whereas only 31 (13.9%) of 223 children with > or =1 report of wheeze developed asthma at 7 years of age, 24 (21.6%) of 111 children with recurrent early wheeze developed asthma at 7 years of age. Among the 12 children with frequent early wheeze, 6 (50%) had asthma at 7 years of age. After adjustment for other covariates, recurrent early wheeze in children at risk for atopy was associated with a fourfold increase in the odds of asthma at 7 years of age, and frequent early wheeze was associated with an approximately 12-fold increase in the odds of asthma at 7 years of age. Most (94%) of the children without frequent early wheeze did not develop asthma at 7 years of age.CONCLUSIONS: The absence of recurrent early wheeze indicates a very low risk of asthma at school age among children with parental history of asthma or allergies. Early identification of children who will develop asthma at school age is difficult, even in children at risk for atopy. However, children with parental history of asthma or allergies who have

frequent early wheeze, in particular, are at greatly increased risk of asthma and merit close clinical follow-up..


Chest. 2005 Feb;127(2):502-8.Early life risk factors for current wheeze, asthma, and bronchial hyperresponsiveness at 10 years of age.Arshad SH, Kurukulaaratchy RJ, Fenn M, Matthews S.Source Department of Respiratory Medicine, University Hospital of North StaffordshireSTUDY OBJECTIVES: We sought to identify early life factors (ie, first 4 years) associated with wheeze, asthma, and bronchial hyperresponsiveness (BHR) at age 10 years, comparing their relative influence for these conditions.RESULTS: Independent significance for current wheeze occurred with maternal asthma (odds ratio [OR], 2.08; 95% confidence interval [CI], 1.27 to 3.41) and paternal asthma (OR, 2.12; 95% CI 1.29 to 3.51), recurrent chest infections at 2 years (OR, 3.98; 95% CI, 2.36 to 6.70), atopy at 4 years of age (OR, 3.69; 95% CI, 2.36 to 5.76), eczema at 4 years of age (OR, 2.15; 95% CI, 1.24 to 3.73), and parental smoking at 4 years of age (OR, 2.18; 95% CI, 1.25 to 3.81). For CDA, significant factors were maternal asthma (OR, 2.26; 95% CI, 1.24 to 3.73), paternal asthma (OR, 2.30; 95% CI, 1.17 to 4.52), and sibling asthma (OR, 2.00; 95% CI, 1.16 to 3.43), recurrent chest infections at 1 year of age (OR, 2.67; 95% CI, 1.12 to 6.40) and 2 years of age (OR, 4.11; 95% CI, 2.06 to 8.18), atopy at 4 years of age (OR, 7.22; 95% CI, 4.13 to 12.62), parental smoking at 1 year of age (OR, 1.99; 95% CI, 1.15 to 3.45), and male gender (OR, 1.72; 95% CI, 1.01 to 2.95). For BHR, atopy at 4 years of age (OR, 5.38; 95% CI, 3.06 to 9.47) and high social class at birth (OR, 2.03; 95% CI, 1.16 to 3.53) proved to be significant.CONCLUSIONS: Asthmatic heredity, predisposition to early life atopy, plus early passive smoke exposure and recurrent chest infections are important influences for the occurrence of wheeze and asthma at 10 years of age. BHR at 10 years of age has a narrower risk profile, suggesting that factors influencing wheezing symptom expression may differ from those predisposing the patient to BHR.


Pediatrics. 2004 Feb;113(2):345-50.Does environment mediate earlier onset of the persistent childhood asthma phenotype?Kurukulaaratchy RJ, Matthews S, Arshad SH.Source The David Hide Asthma and Allergy Research Centre, St Mary's Hospital, Newport, Isle of Wight, UK.OBJECTIVE: We investigated the role of environmental and hereditary factors in determining whether persistent childhood wheezing phenotypes had an early or late onset.METHODS: In a whole population birth cohort (n = 1456), children were seen at birth and at 1, 2, 4, and 10 years. At each visit, information was collected prospectively regarding wheeze prevalence and used to classify subjects into wheezing phenotypes. Information on genetic and environmental risk factors in early life was also obtained prospectively, and skin-prick testing to common allergens was performed at 4 years.RESULTS: Early-onset persistent wheezers (n = 125) had wheeze onset in the first 4 years, still present at age 10, whereas late-onset persistent wheezers (n = 81) had wheeze onset after age 4 years that was still present at 10 years. Multivariate logistic regression analysis identified independent significance only for inherited factors (parental asthma, family history of rhinitis, eczema at 4 years, and atopic status at 4 years) in the development of late-onset persistent wheeze. However, low social class at birth, recurrent chest infections at 2 years, and parental smoking at 2 years plus inherited factors (eczema at 2 years; food allergy at 4 years; maternal asthma, sibling asthma, maternal urticaria, and atopic status at 4 years) demonstrated independent significance for early-onset persistent wheeze.CONCLUSION: Inheritance seems to be of prime significance in the cause of persistent childhood wheeze. Environmental exposure in early life may combine with this tendency to produce an early onset of persistent wheeze. Absence of these environmental factors might delay but not prevent the onset of wheeze in children with atopic heredity.


Eur Respir J. 2003 Nov;22(5):767-71.Predicting persistent disease among children who wheeze during early life.Kurukulaaratchy RJ, Matthews S, Holgate ST, Arshad SH.SourceThe David Hide Asthma & Allergy Research Centre, St Mary's Hospital, Newport, Isle of Wight, UK.AbstractThis study sought to determine factors influencing the persistence of early life wheezing up to the age of 10 yrs and to create a score identifying those with the highest risk of persistent disease. Children were seen at birth, 1, 2, 4 and 10 yrs in a whole population birth cohort study (n=1,456). Information was collected prospectively on wheeze prevalence and subjects were classified into wheezing phenotypes. Early life genetic and environmental risk factors were recorded and skin-prick testing (SPT) was performed at 4 yrs. Independently significant factors for persisting wheeze were identified at logistic regression and used to create a score for persistence. Wheezing persistence from the first 4 yrs to the age of 10 yrs occurred in 37% of early life wheezers. Independent significance for persistence was associated with asthmatic family history, atopic SPT at 4 yrs and recurrent chest infections at 2 yrs, whilst recurrent nasal symptoms at 1 yr conferred reduced risk. A cumulative risk score using these factors identified wheezing persistence in 83% scoring 4 and transience in 80% scoring 0. Thus, a combination of genetic predisposition, early life atopy and recurrent chest infections favours the persistence of early life wheezing. Risk scores using such knowledge could provide prognostic guidance on the outcome of early wheeze.


Artigo importante anterior à buscaAm J Respir Crit Care Med. 2000 Oct;162(4 Pt 1):1403-6.A clinical index to define risk of asthma in young children with recurrent wheezing.Castro-Rodríguez JA, Holberg CJ, Wright AL, Martinez FD.SourceRespiratory Sciences Center, University of Arizona, College of Medicine, Tucson, Arizona, USA.AbstractBecause most cases of asthma begin during the first years of life, identification of young children at high risk of developing the disease is an important public health priority. We used data from the Tucson Children's Respiratory Study to develop two indices for the prediction of asthma. A stringent index included frequent wheezing during the first 3 yr of life and either one major risk factor (parental history of asthma or eczema) or two of three minor risk factors (eosinophilia, wheezing without colds, and allergic rhinitis). A loose index required any wheezing during the first 3 yr of life plus the same combination of risk factors described previously. Children with a positive loose index were 2.6 to 5.5 times more likely to have active asthma between ages 6 and 13 than children with a negative loose index. Risk of having subsequent asthma increased to 4.3 to 9.8 times when a stringent index was used. We found that 59% of children with a positive loose index and 76% of those with a positive stringent index had active asthma in at least one survey during the school years. Over 95% of children with a negative stringent index never had active asthma between ages 6 and 13. We conclude that the subsequent development of asthma can be predicted with reasonable accuracy using simple, clinically based parameters.


4.Análise da qualidade do material selecionado

• Para analisar a literatura científica é necessário:– Ter objetivos bem claros– Ter temas e perguntas bem definidos e– Saber a que se destinam as publicações

selecionadas– Saber analisar a metodologia e conhecer os

níveis de evidência científica


• Todos os artigos têm algum grau de evidência científica, mas nem sempre ela é totalmente confiável.

• A força e a qualidade das evidências estão relacionadas ao tipo de delineamento de estudo.


• Analisando a pesquisa encontraram-se apenas artigos relevantes, provenientes, na sua maioria de estudos de coorte.

• Atualmente, as várias organizações de saúde (OMS, American College of Physicians, UptToDate, Cochrane Collaboation), utilizam o Sistema GRADE (Grading of Recommendations, Assessment, Development and Evaluation) para emitir recomendações (BMJ 2008;336:924 ).

• Sistema GRADE: Uma proposta que combina a força da recomendação e qualidade da evidência para orientar quais condutas devem ser adotadas ou evitadas na prática clínica.


5. Identificação das conclusões que têm repercussão na prática médica

• Aplicação dos resultados à duvida gerada pelo atendimento do paciente.

• Baseado nas informações encontradas poder-se-ia dizer, respondendo a angustia da mãe que existe, nas condições da pergunta, risco maior do seu filho vir a apresentar asma no futuro, com razoável nível de evidência científica.


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