Evolution of Life Expectancy and Lifespan Variation in Sub-Saharan Africa

Despite recent progress, Sub-Saharan Africa (SSA) continues to have the lowest life expectancy and poorest health outcomes globally. While monitoring life expectancy trends is essential, a comprehensive understanding of mortality reduction requires examining age-specific death distributions. Using data from the 2024 Revision of the UN World Population Prospects, we analyze trends in life expectancy and lifespan variation across 49 SSA countries from 1950 to 2023, with projections to 2050, to assess the impact of mortality changes at young, adult, and old ages. We examine three periods--1950-1979, 1980-2004, and 2005-2023--selected based on key epidemiological milestones, including the emergence of the HIV epidemic and the launch of major global health initiatives around 2000. The impact of mortality reductions varies by age group, resulting in differing patterns of life expectancy gains and lifespan variation. Reductions in child mortality consistently contributed to increased life expectancy and decreased variation, while mid- and old-age mortality showed contrasting trends. Notably, this study offers a novel contribution by examining the impact of HIV-related mortality shocks on lifespan variation. Our findings challenge conventional frameworks--such as the demographic and epidemiological transitions--in capturing the complexity of mortality change in SSA and call for a reevaluation of prevailing narratives.