Infant mortality, cancer, and cardiovascular disease mortality: An ecological analysis for 47 prefectures of Japan

Abstract

Infant mortality rates are widely used as an index of past living conditions [ 1 Barker D.J. Fetal nutrition and cardiovascular disease in later life. Br Med Bull. 1997; 53: 96-108 Crossref PubMed Scopus (272) Google Scholar , 2 Barker W.H. Mullooly J.P. Getchell W. Changing incidence and survival for heart failure in a well-defined older population, 1970–1974 and 1990–1994. Circulation. 2006; 113: 799-805 Crossref PubMed Scopus (203) Google Scholar , 3 Leon D.A. Davey Smith G. Infant mortality, stomach cancer, stroke, and coronary heart disease: ecological analysis. BMJ. 2000; 320: 1705-1706 Crossref PubMed Scopus (69) Google Scholar ]. Leon and Smith observed a significant correlation between infant mortality in 1921–1923 and mortality from stomach cancer and stroke among those aged 65–74 in 1991–1992 [ [3] Leon D.A. Davey Smith G. Infant mortality, stomach cancer, stroke, and coronary heart disease: ecological analysis. BMJ. 2000; 320: 1705-1706 Crossref PubMed Scopus (69) Google Scholar ]. In their study, they used data from multi racial/ethnic populations of 27 countries. However, it was unknown whether this association between living conditions in childhood (assessed by infant mortality) and mortality risk from cancer and cardiovascular disease (i.e., two major forms of ischemic heart disease and stroke) in later life exists within one race/ethnicity population. To answer this question, we applied data from Japanese vital statistics, in which infant mortality and mortality from disease-specific causes have been recorded for each of 47 prefectures of the country since 1935. We hypothesize that elevated infant mortality rates (i.e., an index of poorer living condition) is associated with increased mortality rates from stomach cancer, ischemic heart disease and stroke among adults who were born in the period of having high infant mortality.