Fatores de risco associados à mortalidade infantil no município de Cuiabá - MT, 2006-2010

Abstract

Infant mortality is an important health indicator that reflects the quality of health services and living conditions of a population. Objectives: To estimate infant mortality rates (IMR) and its components before and after database linkage between Live Birth Information System (SINASC) and Mortality Information System (SIM) and to investigate risk factors associated with infant mortality in the capital of Mato Grosso in the period 2006-2010. Methods: This dissertation was divided in two observational studies, both related to five cohorts of live births (LB) of the city of Cuiabá, 2006-2010. The first study was to estimate IMR and its components before and after linkage between SINASC and SIM. To identify children that died during the first year of life, it was used the free software Registry Plus™ Link Plus version 3.0 beta, Centers for Disease Control and Prevention. In the second, odds ratio (OR) were calculated as a measure of association between the independent variables and the outcome of infant deaths, with a 95% confidence interval (95%CI). All variables with a p-value<20% in the bivariate analysis were considered in the logistic regression model, according a hierarchical model. Results: In the first study, 617 infant deaths were found in 46.526LB with an IMR of 13.3/1,000 LB, 11.6% lower than that obtained before the linkage method (IMR=15.0/1,000LB). The neonatal mortality rates, early neonatal, late neonatal were approximately 10% lower than that obtained by direct method. The main component of IMR was the early neonatal before and after linkage. In another study, of the 617 infant deaths, 67.1% occurred in the neonatal period, mainly in the early neonatal period (48%). The variables that remained associated independently as risk after logistic regression were: marital status without a partner (OR=1.28; 95%CI: 1.02-1.61); number of prenatal consultations <7 (OR=1.52; 95%CI: 1.24-1.86); live birth weight <2,500grams (OR=4.21; 95%CI: 3.21-5.52), gestational age <37 weeks (OR=2.69; 95%CI: 2.05-3.54); Apgar <7 at 1 minute (OR=3.01; 95%CI: 2.37-3.82), Apgar <7 at 5 minutes (OR=3.23; 95%CI: 2.50- 4.16), presence of congenital malformation (OR=7.14; 95%CI: 5.12-9.97) and male sex (OR=1.26; 95%CI: 1.05-1.51). Conclusion: The main cause of infant mortality in the city of Cuiabá remains the neonatal, especially in the population of infants from birth to six days old, as pointed out in another study done in this city in 2005, and is still necessary implementing public policies to reduce early neonatal mortality. The values of the rates estimated by the direct method were higher than those calculated by the record linkage. After logistic regression, risk factors identified associated with infant mortality show the need to increase the number of pre-natal consultations, and implementation of care to the newborn health in the early neonatal period, component that accounts for almost half of infant deaths.