A new study by the Lancet has found that global life expectancy increased by 6.2 years between 1990 and 2021, with reductions in deaths from diarrhea, lower respiratory infections, stroke, and ischemic heart disease driving the improvements. However, the Covid-19 pandemic caused significant setbacks, leading to a net reduction in life expectancy of 1.6 years between 2019 and 2021. Covid-19 also became the second-leading cause of death during this time period, marking a major change in the rankings of leading causes of death for the first time in decades.
The study revealed that the leading causes of death remained consistent from 1990 to 2019, with ischemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections topping the list. Global life expectancy improved in this time period due to annual reductions in deaths from all causes, ranging from 0.9% to 2.4%. Changes in life expectancy varied significantly by region, with the super region of Southeast Asia, East Asia, and Oceania seeing the greatest net gain in life expectancy, rising by 8.3 years.
Reductions in deaths from enteric diseases, such as diarrhea and typhoid, also significantly contributed to improvements in life expectancy, estimated to contribute an overall increase of 1.1 years globally. Control of mortality due to diarrheal disease contributed to significant gains in life expectancy in South Asia and Eastern sub-Saharan Africa, with the latter region experiencing the highest increase in life expectancy of any local region at 10.7 years.
The study highlights the dual impact of monumental achievements in preventing deaths from diseases like diarrhea and stroke, while also acknowledging the setbacks caused by the Covid-19 pandemic. The largest decline in life expectancy due to Covid-19 was seen in Latin America and the Caribbean, where it caused a 3.6-year reduction. The Covid-19 pandemic not only directly affected mortality rates but also had indirect effects, with physical distancing measures impacting mortality for other diseases and deferred care-seeking leading to pandemic-related deaths not directly attributable to Covid-19.
This study is the first of its kind to compare deaths from Covid-19 to other leading causes of death, providing valuable insights into the global impact of the pandemic on life expectancy. A previous study published by the Lancet had found that the global life expectancy dropped by 1.6 years due to the Covid-19 pandemic, with the United States experiencing the highest excess mortality rate compared to similar high-wealth nations. The findings underscore the importance of continued efforts to address both traditional leading causes of death and emerging challenges like the Covid-19 pandemic in order to improve global life expectancy.
