title: A population-based study on the causes of mild and severe mental retardation.
abstract: The causes of mental retardation (MR) were studied as part of a multidisciplinary epidemiological case-control study in 151 mentally retarded patients identified by screening four age cohorts (12,882 children) at 8-9 years of age in the province of Kuopio, Finland. The causes of MR in 77 severely retarded (SD < or = -3 SD) and 74 mildly retarded (-2 > SD > -3) children were divided into pre-, peri-, postnatal and unknown groups according to the probable time of onset. The causes were pre-, peri-, postnatal and unknown in 60%, 9%, 8% and 23%, and 22%, 1%, 3% and 74%, in the two populations, respectively. Genetic causes were found in 28% of all 151 cases; the three most common subgroups were trisomy 21, fragile X syndrome and aspartylglycosaminuria (13%, 4% and 2% respectively). The study design used provided reliable information on the causes of MR and also demonstrated those forms of genetic metabolic diseases typical of Finnish inheritance.
authors.affiliation: Department of Pediatrics, Kuopio University Hospital, Finland.
authors.forename: R
authors.initials: R
authors.lastname: Matilainen
authors.forename: E
authors.initials: E
authors.lastname: Airaksinen
authors.forename: T
authors.initials: T
authors.lastname: Mononen
authors.forename: K
authors.initials: K
authors.lastname: Launiala
authors.forename: R
authors.initials: R
authors.lastname: Kääriäinen
mesh_terms: D000117:Acetylglucosamine / Q000031:analogs & derivatives / Q000652:urine; D000367:Age Factors; D001238:Asphyxia Neonatorum / Q000150:complications; D016022:Case-Control Studies; D002543:Cerebral Hemorrhage / Q000150:complications; D002648:Child; D004314:Down Syndrome; D005260:Female; D063647:Fetal Alcohol Spectrum Disorders / Q000150:complications; D005315:Fetal Diseases; D005387:Finland / Q000453:epidemiology; D005600:Fragile X Syndrome; D006801:Humans; D007003:Hypoglycemia / Q000150:complications; D007231:Infant, Newborn; D007239:Infections / Q000150:complications; D008607:Intellectual Disability / Q000453:epidemiology / Q000209:etiology* / Q000235:genetics; D008297:Male
chemical_list: C000009:N-acetylglucosaminylasparagine; D000117:Acetylglucosamine