by income group and geographic location, 1950–2100

Figure 2.3 Percentage of population 65+ years of age, by income group and geographic location, 1950–2100

a. Income group b. Geographic location

age of ars ye population 65+ rc ent of Pe 30

20

10 30

20

10

0

1950 2000 2050 2100 0

1950 2000 2050 2100

LMICs UICs UMICs LICs Africa Europe North America Asia Latin America Oceania

Source: Data from the World Population Prospects 2019 website curated by the United Nations Department of Economic and Social Affairs, Population Division (2019). Note: HICs = high-income countries, LICs = low-income countries, LMICs = low- and middleincome countries, and UMICs = upper-middle-income countries.

aging populations, even as these countries’ working-age populations shrink— exactly the demographic whose contributions would have been expected to finance the rising use of complex medical services among the aged. Under these conditions, health systems face powerful pressures to boost efficiency and rein in costs. The proven capacity of strong PHC to contain costs offers a crucial advantage. High-performing PHC has been regularly found to reduce unnecessary hospitalizations and costly emergency room visits, offering cheaper and better management of high-prevalence chronic conditions—for example, diabetes, asthma, hypertension, and congestive heart failure—in community settings at unit costs far below those that apply in higher-level health facilities (OECD 2020). The health promotion and disease prevention facets of PHC offer a powerful means to lower longer-term treatment costs and ensure the future solvency of systems.

Meanwhile, health systems in LMICs have an even more pressing need to make sure that limited health resources are used efficiently.

29

30

The promotion and prevention logic applies even more strongly in these contexts. So, increasingly, does the imperative to manage chronic conditions in community settings where costs are much lower. This argument gains strength as the absolute numbers of older citizens rise, together with the prevalence of multiple comorbidities and “lifestyle” diseases (such as obesity and diabetes) once seen largely in rich countries. In LMICs with rapidly growing younger populations, another key advantage of PHC is its capacity to efficiently deliver key maternal and child health services, along with promotive, preventive, and curative services that can boost the productivity of working-age populations; these services include nutritional supplementation, malaria prevention and treatment, treatment of minor injuries, and routine monitoring of vision and hearing. Such PHC services are critical to build and protect the human capital embodied in LMICs’ young people and working adults—the cornerstone of the economic futures of the respective countries.

Longer, healthier lives—but not for all

Global average life expectancy at birth rose from 65.4 years in 1990 to 72.6 years in 2018. Low-income countries (LICs), however, lag more than a decade behind the global average, although the gap narrowed from 14.7 to 11.8 years during this period.2 This persistent gap in life expectancy is driven by diverse factors, including high rates of maternal and child mortality, ongoing impact of the HIV pandemic, proliferating conflict and violence, and inadequate access to quality health care services.3

Healthy life expectancy (HALE) is a summary measure that combines changes in mortality and nonfatal health outcomes (Salomon et al. 2012). As such, HALE may provide a clearer snapshot of overall population health than life expectancy per se. Global average HALE at birth increased from 58.5 years in 2000 to 63.3 in 2016 (WHO 2019a). Although this is a welcome trend, the difference in 2016 between life expectancy and HALE at birth was some nine years, a stark reminder that many people will spend a substantial portion of their later lives afflicted by chronic illness that in many cases could have been prevented (figure 2.4). Wide disparities in HALE persist across countries at different income levels. In 2000, the average HALE in LICs was about 12.6 years below the global average. This gap narrowed to about nine years by 2016, but the contrast with HICs remains striking. The average HALE in HICs exceeds the global average by almost seven years. In this context, the proven capacity of high-performing PHC to narrow health equity gaps within and between countries takes on increased salience (Hone, Macinko, and Millett 2018). Multiple systematic reviews confirm the evidence base that associates strong PHC with lower health inequalities (Salomon et al. 2012).