Severe mental retardation in Swedish children born 1959-1970: epidemiological panorama and causative factors.
The findings from two recent Swedish retrospective studies on severely mentally retarded children born 1959-70 are surveyed. One study concerned an average county--Uppsala--in the middle of Sweden, the other a vast northern county, Västerbotten, with a sparse population. Figures for incidence and prevalence are given, as well as the percentage distribution of aetiological/pathogenic groups and subgroups, and the frequency of multihandicaps. Prenatal causes were apparent in about 70% of affected children, Down syndrome being the main condition (32%). A background of mutant genes in severe mental retardation was found significantly more often in Västerbotten than in Uppsala (17% and 7% respectively). Perinatal causes were revealed in 10 and 8% (9% of the two series pooled together) and postnatal causes in only 3 and 1% (2%). Associated CNS handicaps were present in about half of the children (42% in Uppsala and 52% in Västerbotten), with epilepsy in 30 and 36%, cerebral palsy in 18% and 19%, and a combination of epilepsy and cerebral palsy in 8 and 16%, respectively.
D000293:Adolescent; D001238:Asphyxia Neonatorum / Q000150:complications; D001724:Birth Weight; D001925:Brain Damage, Chronic / Q000453:epidemiology; D001928:Brain Diseases, Metabolic / Q000150:complications; D002543:Cerebral Hemorrhage / Q000150:complications; D002547:Cerebral Palsy / Q000453:epidemiology / Q000209:etiology; D002648:Child; D002675:Child, Preschool; D002869:Chromosome Aberrations / Q000150:complications; D025063:Chromosome Disorders; D003710:Demography; D004314:Down Syndrome / Q000453:epidemiology; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008607:Intellectual Disability / Q000453:epidemiology* / Q000209:etiology / Q000235:genetics; D009154:Mutation; D011247:Pregnancy; D013548:Sweden