Increasing Mortality Dispersion in the Developed Countries: Aging, Epidemiologic Transition, or Other Mechanisms?

Hui Zheng, Ohio State University
Kenneth C. Land, Duke University

This paper investigates historical changes in mortality rates and mortality dispersions over the past two centuries in 15 developed countries using an integrated Hierarchical Age-Period-Cohort—Variance Function Regression Model. We find that (1) mortality rates accelerate across the adult ages among all countries except in the U.S.; (2) mortality rates substantially declined across cohorts while are relatively flat across time periods; (3) mortality dispersions increase over the life course; (4)mortality dispersions significantly declined across cohorts born after the early 20th century; (5) mortality dispersions continuously declined over much of the last two centuries but have substantially increased since 1980. Further analysis suggests the recent increases in mortality dispersions are not due to increasing proportions of older adults in the population, or disproportionate delay in the deaths from degenerative and man-made diseases, but due to increasing dispersions in young and middle adults. Distinct U.S. patterns are observed in some findings.