Top 10 Leading Causes of Death Globally

The World Health Organization (WHO), in its World Health Statistics 2024 report, revealed that the top 10 causes of death in 2021 accounted for approximately 39 million deaths, making up 57% of the total 68 million deaths worldwide. The COVID-19 pandemic significantly altered global mortality trends, leading to a resurgence of communicable diseases and a decline in life expectancy.

This article delves into the top 10 leading causes of death globally, examining their impact, trends, and underlying risk factors.

The Impact of the COVID-19 Pandemic on Global Mortality

The COVID-19 pandemic has profoundly influenced global health, reversing over a decade’s progress in life expectancy at birth and healthy life expectancy (HALE) within just two years. According to WHO:

• Global life expectancy dropped by 1.8 years, reaching 71.4 years in 2021.
• Healthy life expectancy (HALE) decreased by 1.5 years, falling to 61.9 years.

Additionally, the proportion of non-communicable disease (NCD) deaths declined from 70.0% in 2020 to 65.3% in 2021, whereas deaths due to communicable diseases surged from 23.0% in 2020 to 28.1% in 2021—a level last seen in 2005.

Top 10 Leading Causes of Death Globally

Rank	Cause of Death	Deaths (Millions)	Percentage of Total Deaths	Key Risk Factors
1	Ischaemic Heart Disease	9.0	13.2%	Unhealthy diet, physical inactivity, obesity, smoking, alcohol, diabetes, high cholesterol
2	COVID-19	8.7	12.8%	High transmission, complications in elderly, healthcare strain, emerging variants
3	Stroke	7.0	10.2%	High blood pressure, diabetes, smoking, alcohol, obesity, atrial fibrillation
4	Chronic Obstructive Pulmonary Disease (COPD)	3.5	5.2%	Smoking, air pollution, chemical exposure, genetic factors
5	Lower Respiratory Infections	2.5	3.6%	Weakened immune system, air pollution, smoking, lack of healthcare access
6	Trachea, Bronchus, and Lung Cancers	1.9	2.7%	Smoking, air pollution, occupational exposure to carcinogens
7	Alzheimer’s Disease and Other Dementias	1.8	2.7%	Aging, genetics, lifestyle, cardiovascular diseases
8	Diabetes	1.6	2.4%	Unhealthy diet, obesity, inactivity, genetic predisposition
9	Kidney Diseases	1.4	2.1%	Diabetes, hypertension, obesity, high salt/protein diet, late diagnosis
10	Tuberculosis (TB)	1.4	2.0%	HIV/AIDS, malnutrition, poor living conditions, lack of healthcare access

Top 10 Leading Causes of Death Globally

The top 10 causes of death highlight the growing burden of non-communicable diseases (NCDs) while also underscoring the deadly impact of infectious diseases like COVID-19 and tuberculosis. Below is a detailed breakdown of each cause.

1. Ischaemic Heart Disease (9.0M deaths, 13.2% of total deaths)

Ischaemic heart disease (IHD) remains the leading cause of death globally. Since 2000, deaths from IHD have increased significantly, primarily due to:

• Unhealthy diets (high in saturated fats, sugar, and salt)
• Physical inactivity
• Obesity and hypertension
• Tobacco and alcohol consumption
• Diabetes and high cholesterol levels

2. COVID-19 (8.7M deaths, 12.8% of total deaths)

Emerging as a major cause of death in 2020, COVID-19 became the second-leading global cause of death in 2021, responsible for 8.7 million deaths. Its devastating impact was due to:

• High transmission rates
• Severe complications, particularly in the elderly and those with pre-existing conditions
• Global healthcare system strain
• Emergence of variants leading to increased fatalities

3. Stroke (7.0M deaths, 10.2% of total deaths)

A stroke occurs when the blood supply to the brain is disrupted, often due to a clot or rupture in a blood vessel. Major risk factors include:

• High blood pressure (hypertension)
• Diabetes
• Smoking and excessive alcohol consumption
• Obesity and sedentary lifestyle
• Atrial fibrillation (irregular heart rhythm)

4. Chronic Obstructive Pulmonary Disease (COPD) (3.5M deaths, 5.2% of total deaths)

COPD is a chronic lung disease that restricts airflow and makes breathing difficult. Major risk factors include:

• Long-term exposure to air pollution
• Cigarette smoking
• Occupational exposure to chemicals and dust
• Genetic factors (e.g., alpha-1 antitrypsin deficiency)

5. Lower Respiratory Infections (2.5M deaths, 3.6% of total deaths)

These infections, including pneumonia and bronchitis, are among the leading communicable disease killers. Key causes and risk factors include:

• Weakened immune systems (due to malnutrition, aging, or chronic illnesses)
• Air pollution and smoking
• Lack of access to healthcare and vaccines

6. Trachea, Bronchus, and Lung Cancers (1.9M deaths, 2.7% of total deaths)

Lung cancer remains the most deadly cancer worldwide, primarily caused by:

• Tobacco smoke (90% of cases linked to smoking)
• Air pollution (indoor and outdoor)
• Occupational exposure to carcinogens (e.g., asbestos)

7. Alzheimer’s Disease and Other Dementias (1.8M deaths, 2.7% of total deaths)

Neurodegenerative diseases like Alzheimer’s are on the rise due to aging populations. Major risk factors include:

• Age (primary risk factor)
• Genetics
• Lifestyle factors (diet, physical activity, mental stimulation)
• Cardiovascular diseases (high blood pressure, diabetes)

8. Diabetes (1.6M deaths, 2.4% of total deaths)

Diabetes-related deaths have surged by 95% since 2000, primarily due to:

• Unhealthy diets high in sugar and processed foods
• Obesity
• Physical inactivity
• Genetic predisposition

9. Kidney Diseases (1.4M deaths, 2.1% of total deaths)

Chronic kidney disease (CKD) has moved from the 19th to the 9th leading cause of death globally, with cases rising due to:

• Diabetes and hypertension
• Obesity
• High salt and protein diets
• Lack of early detection and treatment

10. Tuberculosis (TB) (1.4M deaths, 2% of total deaths)

TB remains a leading infectious disease killer, especially in low-income countries. Key risk factors include:

• HIV/AIDS (weakened immune systems increase susceptibility)
• Malnutrition and poor living conditions
• Lack of access to healthcare and vaccines