Exposição pré-concepcional, gestacional e durante a lactação a pesticidas domésticos e outros contaminantes e desenvolvimento de leucemias em lactantes no Brasil / Exposure preconception, pregnancy and during lactation to household pesticides and other contaminants and development of leukemia in infants in Brazil

RESUMO

Objetivos: O objetivo do presente estudo foi explorar as relações inaparentes que diversos fatores relativos às exposições ambientais e características individuais existentes em nosso meio, possam ter no processo de desenvolvimento da leucemia na infância. Método: A partir de um banco de dados clínicos e epidemiológicos obtido com estudo caso-controle de base hospitalar sobre fatores de risco para leucemias na infância, foi realizada análise multivariada exploratória por meio do emprego de análise de componentes principais e análise fatorial. Esta investigação é parte de um estudo multicêntrico nacional que incluiu 292 casos de leucemias em crianças com idade entre 0-12 anos e 541 controles da mesma faixa etária, hospitalizados por causas não neoplásicas em hospitais gerais próximos aos centros de origem dos casos. As informações de exposições ambientais selecionadas foram obtidas por meio de entrevista realizadas com mães de casos e controles atavés do questionário padronizado. A análise de componentes principais e a análise fatorial identificaram fatores associados à leucemogênese, procedendo-se em seguida a modelagem logística não condicional. Este processo permitiu determinar a magnitude de associação entre os fatores identificados com o desenvolvimento de leucemias na infância...

ABSTRACT

Objectives: The aim of this study was to explore the unapparent relationshipsthat several factors related to environmental exposures and individualcharacteristics existing in our environment may have on the process ofdeveloping childhood leukemia.Methodology: From a database of clinical and epidemiological data obtained from case-control study of hospital based on risk factors for childhood leukemia, exploratory multivariate analysis was performed the principal component and factor analysis. This investigation is part of a national multicenter study that included 292 cases of leukemia in children aged 0-12 years and 541 controls of similar age, centers of origin of cases and hospitalized for non-neoplastic causes. The information of selected environmental exposures was obtainedthrough interviews with mothers of cases and controls tied to a standardizedquestionnaire. Results: The principal component analysis and factor analysis identified factors associated with leukemogenesis. Further, an unconditional logistic regressionwas carried out aiming to ascertain the magnitude of association between theselected factors, and their composing variables, with childhood leukemia. Themodel displaying the highest power explained 52% of the total variance,including 3 factors, each one of the showing factors loadings higher than 0.6 “conditions related to chemical exposure during pregnancy”, which explained 20% of the variance; “ lifestyle exposures”, such as smoking and hair dyes and hair cosmetics use during pregnancy, explaining 17% of the total variance; and “consumption of health services during pregnancy”, such as X rays and delivery type (cesarean or vaginal delivery), explaining 15% of the total variance. Logistic modeling revealed statistically significant association between childhood leukemia and chemical exposure during pregnancy (OR=1.36; 95% IC=1.16-1.59), and also with consumption of health services during pregnancy (OR=1.27; 95%IC =1.08-1.49)...