Effect Of Environmental Risk Factor On Children With Autistic Disorder And Mental Retardation

Objective:To find environmental risk factors that could induce the autistic disorder and mental retard during pre-pregnant and pregnant period, to provide evidence for the cause of autistic disorder in the future research, since the cause of autistic disorder and mental retard was still unknown.Methods:A case-control study method was performed, and the data was collected by questionnaire. The risk factors of autistic disorder and mental retard were studied respectively by comparing with normal children, matched by sex and age. The high-risk population was screened by CABS with14scores set as screening standard, and the positive screening children was diagnosed by CARS and DSM-Ⅳ by specialist. Mental retard children, whose intelligence were lower than70, was diagnosed by clinician, with a control group consisted by intelligence healthy children, also matched by sex and age. There are five factors in questionnaire, pre-pregnant environmental hazards exposure of parents, prenatal risk factors exposure, infantile risk factors exposure. Single variable and multivariate conditional logistic regression analysis were used to analyze risk factors. The confounding factors were excluded, and the risk factors were found by using logic analysis. Finally the cause of the disease was deduced.Results:297people was screened,209boys and88girls, with an average age of13.4±4.27, boys13.1±4.11and girls14.1±4.58respectively. Condition of276people was meted, and235of the questionnaire were valid, with an effective pass rate of91.80%.96people lower than18years old were diagnosed as autistic disorder. There are77boys and19girls, with an average age of9.8±2.46, boys9.9±3.37and girls9.1±3.82respectively.56children were mild and moderate autistic disorder,40children were severe, and the average scores of CARS was34.6±3.54in boys and34.6±3.98in girls.In ABC, the lowest score was25, the highest score was128, the average score was68.3, and the standard deviation was23.59. There were no significant differences in CARS between boys and girls, for the P value was lower than0.05by the method of t test and χ2test. There were no significant differences in total scores of ABC between boys and girls, and also no significant differences in every parts of scores of ABC between different age groups and different genders. There were159children younger than18years old age with mental retard,109boys and50girls. The total average age of mental retard children was12.5±3.09,12.3±3.08in boys and12.8±3.13in girls.After exclusive confounding factors among89children,5risk factors of related autistic disorder were found by univariate analysis of conditional Logistic regression analysis. These were pregnant maternal age older than26years old age, paternal character, mother suffering from second hand smoking during bearing baby, neonatal asphyxia, neonatal jaundice. Multivariate analysis was performed according to the important period of brain development. The analyzes were divided into two parts, one for general parents situation, the other for infantile situation. The risk factors which had significant differences in autistic disorder in parents were introduced into the equation. After Multivariate analysis, the risk factors of autistic disorder in general parents situations were found pregnant maternal age older than26years old age, introverted paternal character and mother suffering from second hand smoking during baby bearing. The odd ratio and OR95%CI was2.210(1.070～4.567),5.154(1.307～20.315),1.636(1.018～2.628) and1.790(1.104～2.903), respectively. The risk factors of autistic disorder in baby’s situation was neonatal asphyxia and neonatal jaundice, the odd ratio and OR95%CI was9.000(1.140～71.038) and4.000(1.129～14.175). Mother’s age more than27was the only risk factor found in all autistic disorder groups, and was proved with significant differences.During mental retard risk factors analysis, financial condition during baby born was confounding factors, this variable was defined as stratification factor in univariate analysis of conditional Logistic regression analysis, to avoid its interference effect. After exclusive confounding factors,6risk factors of related autistic disorder were found with significant differences in univariate analysis of conditional Logistic regression analysis. They are, taking folic and vitamin during pregnancy, pregnant maternal emotion, maternal age older than26and paternal age older than30, neonatal asphyxia and neonatal jaundice. During multivariate analysis which was performed according to the important period of brain development, the risk factors of mental retard in general parents situations were taking folic during pregnancy, pregnant maternal emotion, maternal age older than26and paternal age older than30. The odd ratio and OR95%CI was0.251(0.073～0.872),5.987(1.568～22.861)and2.515(1.291～4.901), respectively, and the protective factor was taking folic during pregnancy. neonatal asphyxia and neonatal jaundice were induced in the multivariate equation, and the odd ratio and OR95%CI was21.814(2.515～189.238) and14.285(2.977～68.551) respectively.Conelus i on:Too old maternal age, introverted paternal character, passive smoking, neonatal asphyxia, neonatal jaundice were found to be the incentive cause of autistic disorder after multivariate analysis. Too old parents age, maternal emotion, neonatal asphyxia, neonatal jaundice, which may affect the development of nervous and intelligence, would result in mental retard0In conclusion, those parents and baby related factors run a risk of inducing autistic disorder and mental retard, which should be placed more attention during the disease mechanism research.