While life expectancy has increased in all OECD countries over the past half century, progress was stalling in the decade prior to the COVID‑19 pandemic, and many countries experienced outright drops in life expectancy during the pandemic. In 2021 life expectancy at birth was 80.3 years on average across OECD countries (Figure 3.1). Japan, Switzerland and Korea led a large group of 27 OECD member countries in which life expectancy at birth exceeded 80 years. A second group, including the United States, had life expectancy between 75 and 80 years. Latvia, Lithuania, Hungary and the Slovak Republic had the lowest life expectancy among OECD countries, at less than 75 years. Provisional Eurostat data for 2022 point to a strong rebound in life expectancy in many Central and Eastern European countries, but a more mixed picture for other European countries, including reductions of half a year or more in Iceland, Finland and Norway.

The evolution in all-cause mortality measures whether, and if so to what extent, the total number of deaths from all causes is over and above what could normally be expected for a given period. Here, the numbers of deaths reported in 2022 are compared to the average of the five years prior to the onset of the COVID‑19 pandemic (2015 to 2019). The rationale is to create an annual indicator of how all-cause mortality is evolving across countries in relation to mortality before the COVID‑19 pandemic, to see any direct or indirect effects on mortality rates, as well as whether any other factors are keeping mortality high in OECD countries. While the evolution in all-cause mortality, and excess mortality, proved particularly useful in providing a better understanding of the impact of COVID‑19 across countries (Morgan et al., 2020[1]), it continues to be an insightful indicator for post-COVID‑19 measurement of overall mortality trends.

In 2021, over 12 million people died across OECD countries – equivalent to 932 deaths per 100 000 population (Figure 3.5). This is almost 1.5 million more than in 2019, largely due to COVID‑19. Diseases of the circulatory system and cancer remain the two leading causes of death in most countries. There is an ongoing epidemiological transition from communicable to non-communicable diseases in many middle‑income countries, which has already taken place in high-income countries (Vos et al., 2020[1]). Across OECD countries in 2021, heart attacks, strokes and other circulatory diseases caused more than one in four deaths; around one in five deaths were related to cancer. Population ageing largely explains the predominance of deaths from circulatory diseases – with deaths rising steadily from age 50.

Indicators of avoidable mortality offer a general “starting point” to assess the effectiveness of public health and healthcare systems in reducing deaths from various diseases and injuries. Avoidable mortality includes both preventable deaths that can be avoided through effective public health and prevention interventions, and treatable deaths that can be avoided through timely and effective healthcare interventions. COVID‑19 is categorised as a preventable disease in the “infectious diseases” category, on the basis that most deaths could be prevented through measures such as vaccination and the use of protective equipment.

The COVID‑19 pandemic has shown the global impact of public health threats. As not all lessons from previous health crises such as the 2009 H1N1 flu pandemic were applied before the COVID‑19 pandemic, countries could learn vastly from this experience to be better prepared in the future. Recent OECD work has highlighted three major vulnerabilities that health systems faced during the pandemic – they were underprepared, understaffed, and suffered from underinvestment (OECD, 2023[1]). Addressing these vulnerabilities is critical to strengthening the resilience of health systems to future crises.

Circulatory diseases – notably heart attack and stroke – were the main cause of mortality in most OECD countries in 2021, accounting for 28% of all deaths across OECD countries (see Figure 4.5 in section on “Main causes of mortality”). While mortality rates have declined in most OECD countries over time, population ageing, rising obesity and diabetes rates, and delays in diagnoses may hamper further reductions (OECD, 2015[1]). Indeed, prior to the COVID‑19 pandemic, slowing improvements in heart disease and stroke were one of the principal causes of a slowdown in life expectancy gains in many countries (Raleigh, 2019[2]). Furthermore, COVID‑19 may have contributed indirectly to higher death rates from circulatory diseases in some countries, owing to disruptions to acute, primary and preventive care.

Cancer was the second leading cause of death in OECD countries after circulatory diseases, accounting for 21% of all deaths in 2021. Leading causes of cancer-related mortality included lung cancer (20%), colorectal cancer (10.9%), breast cancer (14.7% among women) and prostate cancer (10.1% among men). These four represent almost 44% of all cancers diagnosed in OECD countries. Mortality rates from cancer have fallen in all OECD countries since 2000, although on average the decline has been more modest than for circulatory diseases.

Chronic conditions such as cancer, chronic respiratory problems and diabetes are not only the leading causes of death across OECD countries but also represent a major disability burden among the living. Many chronic conditions are preventable, by modifying major risk factors such as smoking, alcohol use, obesity and physical inactivity. The COVID‑19 pandemic further underscored the impact of chronic conditions on health outcomes from other diseases, as data show that people with underlying health conditions are at higher risk of dying from COVID‑19 (OECD, 2023[1]). The pandemic also contributed to the increase in multimorbidity of chronic conditions and to their late diagnosis and control.

Maternal mortality – the death of a woman during pregnancy or childbirth, or within 42 days of the termination of pregnancy – is an important indicator of a woman’s health status and to assess health system performance. The Sustainable Development Goals set a target of reducing the global maternal mortality ratio to less than 70 deaths per 100 000 live births by 2030 (WHO, 2023[1]).

Good mental health is essential for healthy populations and economies: when people live with poor mental health, they have a harder time succeeding in school, being productive at work, and staying physically healthy (OECD, 2021[1]). The COVID‑19 pandemic seriously disrupted the way people live, work and learn, and fuelled significant increases in mental distress. At the start of the pandemic, the share of the population reporting symptoms of anxiety and depression increased in all OECD countries with available data, and as much as doubled in some countries (Figure 3.19 and Figure 3.20). OECD analysis has shown that population mental health went up and down over the course of the pandemic – typically worsening during periods when infection and death rates were high, or when stringent containment measures were in place. Available data point to some recovery in population mental health as the pandemic situation improved, but also suggest that mental ill-health remains elevated. In Belgium, Korea, the United Kingdom and the United States, data from 2022 typically show small decreases in the share of the population reporting symptoms of depression, compared to 2020. However, the prevalence for 2022 remains at least 20% higher than pre‑pandemic, and in some cases over double or triple the pre‑pandemic rate (Figure 3.19). Persistently high levels of mental distress “beyond” the pandemic could reflect the confluence of multiple crises: the cost-of-living crisis, climate crisis and geopolitical tensions.

How individuals assess their own health provides a holistic overview of both physical and mental health. Adding such a perspective on quality of life complements life expectancy and mortality indicators that only measure survival. Further, despite its subjective nature, self-rated health has proved to be a good predictor of future healthcare needs and mortality (Palladino et al., 2016[1]).