Mental performance of very low birth weight preterm infants: assessment of stability in the first two years of life and factors associated with mental performance

O objetivo do estudo foi investigar a estabilidade do desempenho mental de beb??s prematuros de muito baixo peso ao nascer ao longo dos dois primeiros anos de vida e identificar os fatores associados ao seu desempenho mental. Estudo de coorte com 109 crian??as. A Escala Mental da Bayley Scales of Infant Development ??? Second Edition foi aplicada aos 6, aos 12 e entre 18- 24 meses de idade corrigida. A estabilidade dos escores entre as avalia????es foi investigada atrav??s de an??lise de vari??ncia para medidas repetidas. A associa????o entre as caracter??sticas neonatais e sociais no desenvolvimento mental foi verificada por an??lise multivariada atrav??s de regress??o linear, considerando como desfechos os ??ndices de Desenvolvimento Mental aos 6 meses, 12 meses e entre 18-24 meses de idade corrigida. A m??dia do ??ndice de Desenvolvimento Mental aos 6 meses foi 83,4 (DP: 12,4), aos 12 meses foi 86,4 (DP: 13,9) e aos 18-24 meses foi 73,4 (DP: 14,5). Observou-se uma diminui????o significativa de 13 pontos no escore aos 18-24 meses de idade corrigida. O ??ndice de Desenvolvimento Mental n??o apresentou estabilidade ao longo dos dois primeiros anos de vida nesta popula????o de prematuros, exceto para as crian??as que tiveram pneumonia neonatal, cujo desempenho foi insatisfat??rio em todas as avalia????es. Dos fatores de risco investigados, apenas o sexo masculino e a pneumonia neonatal estiveram associados aos desfechos.The aim of this study was to investigate the stability of mental performance of very low birth weight premature infants during the first two years of life, and to identify factors associated with mental performance.The study included 109 children. The Mental Scale of Bayley Scales of Infant Development ??? Second Edition was administered at 6, 12 and 18-24 months of corrected age. The stability of the scores between assessments was verified by the analysis of variance for repeated measures. The association of the major social and neonatal characteristics with mental development was confirmed using multivariate analysis by linear regression, considering the following outcomes: mental development indices at 6 months, 12 months and between 18-24 months of corrected age. The mean Mental Developmental Index (MDI) was 83.4 (SD: 12.4) at 6 months, 86.4 (SD: 13.9) at 12 months, and 73.4 (SD: 14.5) at 18-24 months. A significant decrease in the mental developmental index (13 points) at 18-24 month corrected age was observed. The Mental development index did not show stability during the first two years of life in this population of preterm infants, except for children with neonatal pneumonia whose performance was unsatisfactory in all assessments. Among the risk factors investigated only male gender and neonatal pneumonia were associated with outcomes