An Epidemiological and Sociological Study of Unexpected Death in Infancy in Nine Areas of Southern England: I: Epidemiology

Abstract
An epidemiological survey of unexpected deaths in infancy covering nine areas of southern England is reported. The areas include specially deprived inner city areas of London, inner and outer suburbs of London, rapidly developing and new towns and their surrounding country districts and a coastal resort. The report is based on 308 cases and 236 controls. Theepidemiological patterns found in respect of time of death, age, sex and season are similar to those reported by previous studies. The characteristic ‘cot death’ age distribution cannot be explained by the inclusion of older infants whose respiratory passages are obstructed by bedding or infection. Possible explanations for a substantial outbreak in one area are considered. Well recognized differences between cases and controls in respect of age of parents, parity, prematurity, twinning, hospital admission and clinic attendance were found to persist and to be essentially similar in all areas despite there being significant differences between the populations. Sociological differences between cases and controls were largest in the most socially deprived areas, illustrated by an illegitimacy rate of 27 per cent in inner north London. Bottle feeding was only significantly associated with unexpected death when the standard of the home was excellent. Where the homes were poor more cases than controls were breast fed.