Infant mortality and famine: a study in historical epidemiology in northern England.

OBJECTIVE To examine whether periodic variations in annual infant mortality were associated with malnutrition and the poor quality of the food supply available to the community. DESIGN Retrospective study of historical epidemiology of infant mortality by time series analysis and family reconstitution of parish registers of burials and baptisms. SETTING Penrith, Cumbria, England, 1557-1812. SUBJECTS A total of 17,500 births during 1557-1812. RESULTS This community in the Eden Valley, Cumbria, close to the Scottish borders, was living under marginal conditions with high mortality and low fertility. Clear oscillations in infant mortality synchronise with the oscillations in the wheat price index which is regarded as a measure of the availability of food to the community, and to pregnant and nursing mothers in particular. Input-output analysis showed that the relationship between the wheat price index (input) and infant mortality (output) was highly significant (p < 0.001). Events during the famine of 1623 have been analysed in detail: high wheat prices during pregnancy caused subsequent severe infant mortality but did not have indirect effects on the subsequent mortality of the surviving children over the age of 1 year. Non-stationary oscillations in neonatal and post neonatal mortality were strongly coherent (p < 0.001) with the wheat price index throughout the period. CONCLUSIONS Infant mortality is particularly sensitive to famine and also to the quality of the food supply available to pregnant and nursing mothers. The lags between neonatal and post-neonatal mortalities and wheat prices, together with the analysis of the famine of 1623, support the hypothesis that neonatal mortality was related to malnutrition in pregnancy whereas post-neonatal mortality was primarily directly dependent on exogenous causes in the first year of life.