CHANGES IN PREVALENCE, ETIOLOGY, AGE AT DETECTION, AND ASSOCIATED DISABILITIES IN PRESCHOOL-CHILDREN WITH HEARING IMPAIRMENT BORN IN GOTEBORG

The prevalence of hearing impairment (HI) in preschool children born i n Goteborg in 1980 to 1984 was 2.0 per1000, This was significantly low er than the 3.8 per 1000 found in a previous study for 1970 to 1974, T he decrease took place in the moderate to severe range of HI, while de afness and mild HI remained unchanged during the period, The cause was considered to be prenatal in 58% with heredity in 33% as the main cau sative factor. Following the introduction of the MPR (Morbilli-Parotit is-Rubella) vaccination programme in Sweden, no cases of rubella- or m umps-induced HI could be found, The number of HI of perinatal origin d ecreased by half, in spite of the fact that the figures for preterm ba by survival almost doubled during the period, Associated disabilities were diagnosed in 62% of the children with HI; speech retardation in 3 3%, visual abnormalities in 30%, mental retardation in 12% and neurops ychiatric disorders in 9% of the cases, The importance of collaborativ e efforts between the otolaryngologist and the neurologically and neur opsychiatrically interested paediatrician in the complete evaluation o f additional difficulties in the HI child is emphasized.