The ten leading causes of death were responsible for 39 million lives lost in 2021 according to WHO – over half of the global total.
Many of these are chronic illnesses, but others, like COVID-19, have emerged more recently and dramatically shifted global health patterns.
1. Ischaemic heart disease
Ischaemic heart disease remains the number one cause of death worldwide, responsible for 13 % of all global deaths in 2021.
Since 2000, deaths from this condition have surged, reaching 9.1 million in 2021 alone.
2. COVID-19
COVID-19 burst onto the list as the second leading cause of death in 2021, claiming 8.8 million lives.
Its rapid spread and impact pushed many other diseases down the rankings, marking a major shift in global mortality.
3. Stroke
Although it was the second leading cause of death prior to the pandemic, stroke fell to third place in 2021.
It still accounted for about 10 % of all global deaths, making it one of the most widespread and lethal conditions.
4. Chronic obstructive pulmonary disease (COPD)
Ranked fourth, COPD caused approximately 5 % of all deaths in 2021.
It’s a progressive, noncommunicable lung disease often linked to smoking and air pollution, and remains a significant health burden.
5. Lower respiratory infections
Lower respiratory infections, such as pneumonia, were the fifth leading cause of death in 2021.
Despite claiming 2.5 million lives, this was a notable decrease compared to 2000, showing improvements in prevention and treatment.
6. Lung, trachea, and bronchus cancers
Deaths from cancers of the trachea, bronchus, and lungs have increased from 1.2 million in 2000 to 1.9 million in 2021.
These cancers ranked sixth and are largely attributed to smoking and environmental pollutants.
7. Alzheimer’s disease and other dementias
Alzheimer’s and other forms of dementia ranked seventh globally, causing 1.8 million deaths in 2021.
Women were disproportionately affected, accounting for 68 % of all dementia-related deaths.
8. Diabetes
Diabetes continued its rise in the rankings, claiming significantly more lives over the past two decades.
Deaths linked to the disease increased by 95 % since 2000, securing its place as the eighth leading cause of death.
9. Kidney diseases
Kidney diseases climbed from 19th place in 2000 to ninth in 2021, with the number of deaths nearly doubling over two decades.
This alarming trend highlights a rising chronic health issue that is often underdiagnosed.
10. Tuberculosis
Tuberculosis (TB) was the tenth leading cause of death in 2021.
Despite being preventable and treatable, TB continues to kill millions, particularly in low- and middle-income countries.
This article is based on information from WHO.