Longevity: Some familial correlates

Abstract

This historical prospective study is aimed at the underscoring of the independent effect of a set of familial characteristics on age at time of death broken down into ten age groups (from 0 through 90 years and over). The study is concerned with the small rural population of Isle‐aux‐Coudres, Quebec. The following familial traits were analyzed: parental consanguinity, maternal and paternal age at time of childbirth, sex, birth order, the interval since the previous birth, month of birth, viability of the preceding infant, the number of deceased family members in the age groups 0–1, 1–4 and more than S years at the time of the child's birth. A multiple discriminant analysis has been worked out first on a birth cohort (1880–99) with no underreporting of infant mortality (Stage 1). Subsequently, four other cohorts were analyzed in the same way (Stage 2). Stage 1 analysis opposes the two extremities of the life span to the age group 5–69 years, and points to maternal age, among other less important variables, as a factor of offspring early (less than 5) or advanced age (over 70) at time of death. Stage 2 analysis shows inconsistencies with Stage 1 results. Taking account of family size, further investigations supported the view that offspring survival to either early or advanced age could vary from family to family.