Non-communicable disease

• Examples of non-communicable diseases

  • Cancer

  • Diabetes

  • Cardiovascular disease

  • Chronic respiratory diseases e.g. asthma
• What is a risk factor?


  A variable associated with a greater chance of developing a disease or infection
• Outline the factors that can affect the risk of developing a non-communicable disease

  • Lifestyle factors e.g. diet, exercise, alcohol, smoking

  • Environmental factors e.g. exposure to radiation

  • Genetics e.g. alleles that increase the risk of cancer
• “Correlation does not mean causation“ explain this statement

  Correlation between a risk factor and disease does not mean that the risk factor causes the disease. Other factors may be involved and some may be linked.
• Describe how exercise affects the risk of some non-communicable diseases

  • Regular exercise decreases fat stores, reducing obesity (a risk of CVD and type 2 diabetes)

  • It decreases heart rate, recovery time and blood pressure, lowering the risk of CVD
• Describe how diet affects the risk of some non-communicable diseases

  • Diet high in saturated fat raises blood cholesterol levels, increasing the deposition of fatty deposits in the arteries - greater risk of CVD

  • Obesity and the consumption of large amounts of simple-sugars increases the risk of type two diabetes

  • Malnourishment increases the risk of deficiency diseases
• Example of a deficiency disease

  • Scurvy (vitamin C deficiency)

  • Anaemia (iron deficiency)
• What is the Body Mass Index (BMI)?


  A value based on height and mass used the categorise an individual as underweight, normal weight, overweight or obese
• How is BMI calculated?

  Mass (kg)/ Height (m)$^2$
• Why isn’t BMI always an accurate measure of obesity?

  Fat and muscle tissue cannot be distinguished so athletes may be incorrectly categorised as obese
• How is an individual’s waist-to-hip ratio be calculated?

  Waist circumference (cm) /hip circumference (cm)
• What does a waist-to-hip ratio higher than 1.0 in males or 0.85 in females indicate?

  • Abdominal obesity

  • Increased risk of developing type 2 diabetes
• Describe how alcohol affects the risk of some non-communicable diseases

  • Alcohol broken down into toxic products in the liver which build-up and cause cirrhosis (scarring of liver tissue)

  • Alcohol raises blood pressure thus increasing the risk of CVD

  • Toxic products in alcohol can cause mutations to DNA, increasing the risk of cancer (mouth, throat, liver etc.)
• Describe how smoking affects the risk of some non-communicable diseases

  • Nicotine raises heart rate, increasing the risk of CVD

  • Carbon monoxide lowers the ability of red blood cells to carry oxygen, heart rate increases, increasing the risk of CVD

  • Carcinogens in tar can cause mutations to DNA, increasing the risk of cancer (mouth, throat, lung etc.)

  • Smoking increases the risk of lung diseases e.g. chronic bronchitis
• How do environmental factors affect the risk of some non-communicable diseases?

  • Long-term exposure to pollution damages the airways, increasing the risk of lung diseases and lung cancer

  • Exposure to UV radiation damages DNA, increasing the risk of DNA mutations and skin cancer
• How do genetics affect the risk of some non-communicable diseases?

  • The risks of some diseases such as type 2 diabetes, lung cancer and CVD are increased if a family member has had these conditions

  • Faulty genes can be inherited which increase the risk of conditions such as breast cancer
• How do diseases interact with each other?

  • Some diseases may cause other infections to develop e.g. HOV weakens the immune system, making an individual more susceptible to other infections such as TB

  • Some diseases reduce the risk of contracting other infections e.g. Trichnosis reduces the development of Crohn’s disease
• Describe the effects of non-communicable disease on a local, national and global level

  • Increases incidence of non-communicable disease puts a strain on local hospitals which have limited resources

  • Increased pressure on NHS to provide treatment to a larger number of patients. Sickness-related absence impacts a country’s economy

  • High prevalence of malnutrition in LEDCs slows the development of such countries, which in turn impacts global development
• What is cardiovascular disease (CVD) ?

  • A group of diseases affecting the heart or blood vessels

  • Build up of fatty deposits on the walls of the arteries forms atheromas which reduce blood flow to muscle tissue

  • Blood clots may form, blocking the arteries and stopping blood flow completely. This can lead to a heart attack or stroke
• How can CVD lead to heart attack?

  • Obstruction of a coronary artery (supplies heart muscle) due to an atheroma or blood clot

  • Results in loss of blood supply to an area of heart muscle

  • This causes death of the cells and leads to a heart attack
• How can CVD be treated?

  • Improving diet and lifestyle

  • Medication

  • Surgery
• What changes to diet and lifestyle can be made to reduce the risk of CVD?

  • Regular exercise

  • Reduce intake of saturated fat

  • Maintenance of a healthy weight

  • Diet low in salt

  • Reduce stress

  • Stop smoking and drinking alcohol
• How effective are changes to lifestyle and diet in treating CVD?

  Although not themselves effective in the treatment of CVD, they can enhance the efficiency of other methods of treatment.
• What medicines are used to treat CVD?

  • Statins

  • Anticoagulants

  • Antihypertensives
• Outline the benefits vs the risks of using statins to treat CVD

  • Statins lower the level of cholesterol in the blood

  • However, they can cause liver damage, kidney failure or problems with memory
• Outline the benefits vs the risks of using anticoagulants to treat CVD

  • Anticoagulants reduce blood clotting, lowering the risk of heart attack or stroke

  • However, they can cause excessive bleeding
• Outline the benefits vs the risks of using antihypertensives to treat CVD

  • Antihypertensives lower blood pressure, reducing damage to artery walls and the build up of arethomas

  • However, they can have unpleasant side-effects such as headaches, dizziness or fainting
• What are stents?


  • Small, hollow tubes inserted into the lumen of arteries to keep them open

  • Require surgery to insert
• What are the problems with the use of stents to treat CVD?

  • Stents cause the growth of scar tissue in the arteries over time, further narrowing the lumen

  • Blood clots may stick to stents
• What is a coronary bypass?

  Using a blood vessel from another region of the body (e.g. leg, arm) to divert blood around a blockage in the coronary artery
• What does a heart transplant involve?

  • Replacing a damaged heart with a donated heart

  • Immunosuppressant drugs taken to prevent organ rejection
• Describe the benefits of heart surgery

  • Lifesaving

  • Can provide a permanent solution to a disease
• Describe the risks of heart surgery

  • Involves many risks e.g. infection, excessive bleeding etc

  • Difficult to find a suitable donor

  • Risk of rejection

  • Immunosuppressant drugs must be taken for life

  • Long recovery time

  • Expensive