Slowdown in mortality improvements and trends in lifespan inequality across high-income countries: the role of changing causes of death, 2010-2021.

backgroundIn recent years, several high-income countries have experienced slowdowns in mortality improvements. Prior research has focused on how those changes have impacted life expectancy, but little is known about how they affected lifespan inequality.

methodsUsing data from the Human Mortality Database and World Health Organization Mortality Database, we quantify the contributions of changes in age- and cause-specific mortality to changes in lifespan inequality, measured by life disparity, across 20 high-income countries between 2010 and 2021.

resultsOn average, life disparity declined by 0.3 years among both females and males between 2010 and 2019, with declines observed in all countries except for Canada and the United States. These declines were largely attributed to reductions in premature mortality, particularly from cardiovascular diseases and malignant neoplasms. Across English-speaking countries, these reductions were partly (e.g. Canada) or entirely (USA) offset by rising premature mortality related to neuropsychiatric conditions-mainly drug and alcohol use disorders. The COVID-19 pandemic was marked by increasing premature and old-age mortality, which partly contributed to the declines in life disparity in several, though not all, countries.

conclusionMortality dynamics since the 2010s have resulted in distinct changes in lifespan inequality, in addition to life expectancy, across high-income countries. Despite the slowdowns in mortality improvements, lifespans in most countries have become more equal in the decade preceding COVID-19. This trend was interrupted or reversed by the pandemic in many countries. Canada and the United Sates stood out in both periods due to rising premature mortality related to drug and alcohol use.