全国0—14岁儿童智力低下的病因流行病学研究

在全国８个城市、６个农村地区对１３８个抽样单位，约１４０万人口中的０～１４岁儿童，采用全国分层的不等比例，多阶段，随机整群抽样的流行病学方法，调查了解我国儿童智力低下的发病原因及其构成，并据此提出防治措施。在已知病因中，生物医学因素占８９６％，社会文化心理因素占１０．４％。在出生前因素中，遗传性疾病占出生前因素的４０．５％，其中以染色体畸变最多，先天性代谢病次之。在出生后因素中，中枢神经系统感染后遗症占２８．２％。在社会文化因素中，文化落后和心理损伤，无论在城市或农村都占有重要地位。

An epidemiological study on etiology of mentalretardation

cross-sectional epidemiological study was conducted to assess the prevalence and etiology of mentalretardation (MR) among children under 14 years ofage. The definition of MR and the criteria fordiagnosis were adopted from WHO (1985). TheIQ / DQ was evaluated with atandardized psychologi-cal tests. The etiology of MR was specified by medical, genetic and psychosocial studies. A total of 862 re-tarded children were found among 85 170 surveyed.The overall adjusted prevalence rate was 1.20%. Thepercentage of mild, moderate, severe and profoundMR was 60.6%, 22.7%, 9.6%, and 7. 1 %, respectively.Specific causes were found in 673 cases (79. 1 %). Theetiology was unknown in 21.9% children. Timing ofthe causes showed prenatal in 34% perinatal 11.9%,postnatal 33%, Biomedical causes consisted of 89.6%and sociocultrual factors, 10.4%. Among the prenatalfactors, genetic diseases ranked first and manifested aschromosomal abnormalities and inborn errors ofmetabolism. Among the postnatal causes, sequalae ofCNS infections and other forms of acquired brain in-sult were most important. Most children ofsocio-cultural MR were at school age and of the mildcategory. Our results show that most MR cases arepreventable.