What Are Non-Communicable Diseases?
Non-communicable diseases (NCDs) are medical conditions or diseases that are not caused by infectious agents and cannot be transmitted from person to person. Unlike communicable diseases, NCDs tend to be long-lasting and progress slowly over time.
They are responsible for the majority of global deaths—claiming nearly 41 million lives each year, which equals about 74% of all global deaths according to the World Health Organization (WHO).
Understanding the causes, types, and prevention of non-communicable diseases is vital for individuals, families, and governments aiming to promote long-term health and reduce healthcare burdens.
Key Characteristics of Non-Communicable Diseases
- They are not infectious (not passed between people).
- They are generally of long duration.
- They tend to be the result of a combination of genetic, physiological, environmental, and lifestyle factors.
- Many NCDs are preventable through healthy behaviour and early intervention.
Major Types of Non-Communicable Diseases
Although there are many NCDs, the following four are responsible for the vast majority of deaths worldwide:
1. Cardiovascular Diseases (CVDs)
CVDs affect the heart and blood vessels. They include conditions such as:
- Heart attacks
- Strokes
- Coronary artery disease
- Heart failure
Risk factors: High blood pressure, high cholesterol, smoking, poor diet, lack of exercise, and diabetes.
2. Cancers
Cancer occurs when abnormal cells grow uncontrollably and invade surrounding tissues. There are over 100 types of cancer, with the most common being:
- Breast cancer
- Lung cancer
- Colorectal cancer
- Prostate cancer
Risk factors: Tobacco use, alcohol, diet, physical inactivity, infections (e.g., HPV), and environmental pollutants.
3. Chronic Respiratory Diseases
These affect the airways and lungs, making breathing difficult. Common examples include:
- Chronic obstructive pulmonary disease (COPD)
- Asthma
- Pulmonary hypertension
Risk factors: Tobacco smoke, air pollution, occupational chemicals, and respiratory infections in early life.
4. Diabetes
Diabetes occurs when the body cannot properly regulate blood sugar levels. The most common types include:
- Type 1 diabetes – often diagnosed in childhood; autoimmune in nature.
- Type 2 diabetes – linked to obesity and lifestyle; more common in adults.
- Gestational diabetes – occurs during pregnancy.
Risk factors: Poor diet, physical inactivity, obesity, genetics, and age.
Other Significant Non-Communicable Diseases
- Kidney diseases – e.g., chronic kidney disease (CKD)
- Mental health conditions – such as depression, anxiety, and bipolar disorder
- Neurological disorders – e.g., Alzheimer’s disease, Parkinson’s disease
- Musculoskeletal conditions – e.g., arthritis, osteoporosis
- Autoimmune diseases – e.g., lupus, multiple sclerosis
Main Causes and Risk Factors
Most non-communicable diseases develop over time due to a combination of modifiable and non-modifiable risk factors.
Modifiable Risk Factors (Lifestyle-related):
- Poor diet (high in sugar, salt, saturated fats)
- Physical inactivity
- Tobacco use
- Excessive alcohol consumption
- Obesity and overweight
- Environmental pollution
Non-Modifiable Risk Factors:
- Genetics or family history
- Ageing
- Ethnicity
- Sex (e.g., men may be more prone to heart disease)
The Global Impact of NCDs
Non-communicable diseases are not only a major cause of death but also a significant contributor to disability and economic loss. According to the WHO:
- 77% of NCD deaths occur in low- and middle-income countries.
- Cardiovascular diseases alone account for 17.9 million deaths each year.
- Economic impact: NCDs reduce workforce productivity, increase healthcare costs, and place strain on national economies.
Prevention of Non-Communicable Diseases
One of the most effective ways to combat NCDs is through prevention. Here are proven strategies:
1. Healthy Diet
- Eat more fruits, vegetables, whole grains, and lean proteins.
- Limit processed foods, sugary drinks, red meats, and trans fats.
- Reduce salt intake to help control blood pressure.
2. Regular Physical Activity
The NHS recommends at least 150 minutes of moderate aerobic activity (like walking or cycling) every week, along with muscle-strengthening activities on two or more days.
3. Tobacco and Alcohol Control
- Quit smoking: Tobacco is a major risk factor for CVDs, cancer, and respiratory illnesses.
- Limit alcohol intake: Excessive drinking increases the risk of liver disease, cancer, and heart problems.
4. Weight Management
Maintain a healthy body mass index (BMI) through balanced nutrition and exercise to lower the risk of diabetes, heart disease, and certain cancers.
5. Regular Health Screenings
Early detection and management of NCDs can prevent complications:
- Blood pressure and cholesterol checks
- Blood sugar tests for diabetes
- Cancer screenings (e.g., breast, cervical, prostate)
- Mental health assessments
The Role of Mental Health in NCDs
Mental and physical health are closely linked. People with long-term NCDs often suffer from depression or anxiety, which can worsen outcomes and reduce treatment adherence. Integrating mental health support into NCD care is essential.
Women and Non-Communicable Diseases
Women face unique challenges with NCDs due to biological, social, and economic factors:
- Cardiovascular disease is the leading cause of death among women globally.
- Women are more likely to be misdiagnosed or underdiagnosed in conditions like heart disease and autoimmune diseases.
- Hormonal changes (e.g., menopause) can increase risk for conditions like osteoporosis and hypertension.
Government and Community Roles in NCD Prevention
- Public health campaigns promoting healthy lifestyles
- Access to affordable healthcare and screenings
- Policies limiting tobacco, sugar, and alcohol consumption
- Urban planning that encourages walking, cycling, and green spaces