The Incidence of Infantile Hydrocephalus in Sweden

Abstract

Summary The incidence of infantile hydrocephalus in Sweden was investigated in two separate studies; the number of cases present at birth was determined in a material from an obstetric clinic; the number of cases with an onset during the first year of life was penetrated in a field study. Among all 43,548 infants delivered at the Obstetric Department of the University Hospital of Uppsala in 1944‐61, malformations of the central nervous system were revealed in 48 cases, i.e. 1.10 per 1000 births. The corresponding figure for hydrocephalic births was 0.78. Hydrocephalus was combined with spina bifida cystica in 0.50 per 1000 births and in 0.49 per 1000 live births, while the corresponding figure for simple hydrocephalus was found to be 0.28 and 0.19 respectively. In the field study made in 1961 and comprising all children born in 1952‐57 in three different Swedish counties a total number of 72 cases with infantile hydrocephalus starting before one year of age was found among 64,630 live births. “Simple” hydrocephalus was present in 55 cases, i.e. 0.85 per 1000 live births. Incomplete information was obtained in this study about the incidence of hydrocephalus in cases with spina bifida cystica. The total incidence per year of new hydrocephalic cases with an onset before one year of age was obtained by adding the frequency figure for hydrocephalus with spina bifida cystica at birth to the frequency figure for “simple” hydrocephalus starting during the first year of life. With this approximation a total incidence of 1.34 per 1000 live births was found, i.e. 22 cases per 1,000,000 in‐habitants, or 14 cases of “simple” hydro‐cephalus and 8 cases combined with spina bifida cystica. The reliability of the frequency figures obtained was checked for “simple” hydrocephalus from experience in practical clinical work during one year, 1961/62, and a good agreement was found.