The Race between Mortality and Morbidity: Implications for the Global Distribution of Health

Abstract

Assessments of countries’ longevity and its variability around the globe often rely on life expectancy (LE) but tend not to differentiate between the years spent in “good” or “less-than-good” health. We explore how the evolution of the healthy and unhealthy components of LE has shaped the composition of LE within countries, and the extent of LE inequality between countries. Using data from the Global Burden of Disease Study, we document the joint evolution of “health-adjusted life expectancy” (HALE) and “unhealthy life expectancy” (UHLE) for 204 countries and territories from 1990 to 2019, the age-specific contributions to changes over time in HALE and UHLE, and the corresponding cause-of-death profiles. We also assess the contribution of HALE and UHLE to “international health inequality” (IHI; i.e., inequality in LE across world countries). Between 1990 and 2019, HALE and UHLE have increased in most world countries, thus lengthening longevity worldwide. Globally, HALE has increased from 58.1 years to 63.4 years, while UHLE has increased from 8.4 years to 9.4 years, but there is a great deal of variation across regions and countries. The fraction HALE/LE has declined in three out of four countries. Over time, IHI followed an inverted U shape, peaking around the year 2000 and declining from that year onwards. IHI levels and trends are mostly explained by trends in HALE. Our findings indicate that global health inequalities are undergoing profound transformations. While health inequalities between countries tend to decline, those within countries tend to increase. In addition, we observe a compositional shift in which the unhealthy component of LE is playing an increasingly important role in explaining (1) further increases in longevity among low-mortality countries and (2) the extent of inequality in LE among world countries. Policies aiming at increasing LE and reducing its variability between countries should increase HALE among the world's least longevous countries.