Global life expectancy has increased 6.2 years since 1990, according to a new study published in The lancet. Over the past three decades, reductions in deaths from leading causes of death have driven this progress, including diarrhea and lower respiratory tract infections, as well as stroke and ischemic heart disease. However, when the COVID-19 pandemic hit in 2020, it derailed progress in many places. This is the first study to compare deaths from COVID-19 with deaths from other causes globally.
Despite the challenges presented by the COVID-19 pandemic, researchers found that the Southeast Asia, East Asia and Oceania superregion had the largest net increase in life expectancy between 1990 and 2021 (8.3 years), at largely due to reductions in life expectancy. mortality from chronic respiratory diseases, stroke, lower respiratory tract infections and cancer. The superregion’s strong management of the COVID-19 pandemic helped preserve these achievements. South Asia had the second largest net increase in life expectancy among superregions between 1990 and 2021 (7.8 years), mainly thanks to a sharp decline in deaths from diarrheal diseases.
“Our study presents a nuanced picture of global health,” said Dr. Liane Ong, co-first author of the study and senior research scientist at the Institute for Health Metrics and Evaluation (IHME). “On the one hand, we see the monumental achievements of countries in preventing deaths from diarrhea and stroke,” she said. “At the same time, we see how much the COVID-19 pandemic has set us back.”
The study also highlights how COVID-19 radically altered the top five causes of death for the first time in 30 years. COVID-19 displaced one of the leading causes of death, stroke, to become the second leading cause of death globally. The research presents updated estimates from the 2021 Global Burden of Disease (GBD) Study. The authors found that the superregions where the COVID-19 pandemic hit hardest were Latin America and the Caribbean and sub-Saharan Africa, which lost the most years. of life expectancy due to COVID-19 in 2021. While documenting the enormous loss of life caused by the COVID-19 pandemic, researchers also identified the reasons behind the improvements in life expectancy in each super region. When analyzing the different causes of death, the study reveals sharp drops in deaths from enteric diseases, a class of diseases that include diarrhea and typhoid fever. These improvements increased life expectancy worldwide by 1.1 years between 1990 and 2021. Reductions in deaths from lower respiratory tract infections added 0.9 years to global life expectancy during this period. Advances in preventing deaths from other causes have also increased life expectancy around the world, including stroke, neonatal disorders, ischemic heart disease and cancer. For each disease, reductions in deaths were most pronounced between 1990 and 2019.
Regionally, Eastern Sub-Saharan Africa experienced the largest increase in life expectancy, which increased by 10.7 years between 1990 and 2021. The control of diarrheal diseases was the main force behind the improvements in this region. East Asia had the second largest increase in life expectancy; The region’s success in dramatically reducing deaths from chronic obstructive pulmonary disease played a key role.
The GBD 2021 study measures mortality by cause of death and years of life lost at the global, regional, national and subnational levels. The analysis links specific causes of death to changes in life expectancy.
The study sheds light not only on the diseases that have driven increases and decreases in life expectancy, but also analyzes how disease patterns have changed between places over time, presenting, as the authors write, an “opportunity to deepen our understanding of mortality reduction. strategies…[which] “could reveal areas where successful public health interventions have been implemented.”
GBD 2021 highlights places that have made great strides in preventing deaths from major illnesses and injuries. It also highlights how some of the most burdensome diseases are now concentrated in certain locations, underscoring opportunities for intervention. For example, in 2021, deaths from enteric diseases were mainly concentrated in sub-Saharan Africa and South Asia. For another disease, malaria, the researchers found that 90% of the deaths occurred in an area inhabited by only 12% of the world’s population in a stretch of land stretching from western sub-Saharan Africa through Africa to Mozambique. central.
“We already know how to prevent children from dying from enteric infections, including diarrheal diseases, and progress in combating this disease has been tremendous,” said Professor Mohsen Naghavi, co-first author of the study and director of subnational burden estimation. IHME diseases. . “We must now focus on preventing and treating these diseases, strengthening and expanding immunization programs and developing new vaccines against E. coli, norovirus and Shigella,” he added.
In addition to providing new insights into COVID-19, the study reveals growing threats from non-communicable diseases, such as diabetes and kidney disease, which are increasing in all countries. Researchers also point to uneven progress against diseases such as ischemic heart disease, stroke and cancer. High-income countries have reduced deaths from many types of noncommunicable diseases, but many low-income countries have not.
“The global community must ensure that the life-saving tools that have reduced deaths from ischemic heart disease, stroke and other non-communicable diseases in most high-income countries are available to people in all countries, even where resources are limited,” said Eve Wool, lead author of the study and senior research director at IHME.