Geographic patterns of population longevity and reproductive longevity in Sardinia
Graziella Caselli, Università di Roma "La Sapienza"
Daniela Pierannunzio, Università di Roma "La Sapienza"
Paola Astolfi, Dept. Genetics and Microbiology "A.Buzzati-Traverso", Pavia, Italy
Laura Attinia Zonta, Dept. Genetics and Microbiology "A. Buzzati-Traverso"
Among the European countries, Sardinia represents the most representative example of human longevity for the highest frequency of centenarians, and of reproductive longevity for traditionally advanced maternal age at delivery associated to reduced risk at birth. The geographical and historical conditions of isolation and cultural traditions of the island are generally accepted as determinants of its genetic structure, and epidemiological and demographic features. The aim of the paper is to single out areas of life and reproductive longevity through the comparison of geographical maps of longevity, late fertility and risk at birth. The underlying hypothesis is that common factors of demo-socio-economic and genetic origin had contributed to shape the geographical profiles of both phenomena. Sardinian municipality data on centenarians are available for the cohorts born between 1889 and 1903 and alive from 1997 to 2004. Municipality data on woman fertility and pregnancy outcome refer to mothers who at the 1961 census were at least 45 year old and in post-reproductive age. Homogenous geographical areas for centenarians, late fertility and stillbirth were identified through Kernel spatial analysis methods. The underlying determinants of the high number of centenarians in Sardinia have been recently discussed in an international research on the bio-demographic features of Sardinian centenarians. This research located an inland area, covering the municipalities of Nuoro and of other bordering districts with a remarkably high number of centenarians. The preliminary geographic analysis on reproductive longevity outlines a very similar geographic situation.