Risk Factors For Non-Communicable Diseases (AQA GCSE Combined Science: Synergy: Life & Environmental Sciences): Revision Note

Definition of Risk Factors

• Risk factors are linked to an increased rate of a disease; but exposure to a risk factor doesn’t guarantee that an individual will suffer a disease (a person who smokes regularly isn’t guaranteed to develop lung cancer but their risk compared to someone who doesn’t smoke is much, much higher)

• Certain risk factors correlate with certain diseases (are related to them); but correlations are not always causations

• Risk factors can be:

  • Aspects of a person’s lifestyle; such as the food they eat or whether or not they drink alcohol

  • Substances in the person’s body or environment; such as air pollution in a crowded city or asbestos in old buildings

Causal mechanisms & risk factors

• A causal mechanism has been proven for some risk factors, but not in others

Examples of Risk Factors

• Many diseases are caused by the interaction of a number of factors; the chance of developing cardiovascular disease is higher in individuals who have a poor diet high in cholesterol (fat), don’t exercise regularly and smoke – because all of these behaviours increase the likelihood of damage occurring to the arteries

Sampling, Translating & Interpreting Data

• Sampling allows researchers to infer (deduce/conclude) information about a population without having to investigate every individual which would be time-consuming and essentially impossible to do accurately

• Scientists sample populations to determine risk factors for different diseases and inform public health policy

  • For example; sampling individuals with type 2 diabetes and identifying patterns or similarities in their lifestyle and health condition allows scientists to deduce that obesity and a diet high in sugar and fat are risk factors for developing this condition (as these factors are found in most individuals who develop type 2 diabetes)

• Scientists present their findings in graphical and numerical forms top identify if there are relationships between risk factors and certain disease

• Scatter diagrams are used to identify correlations between two variables to determine if a factor (such as obesity) does increase the risk of developing a disease (such as type 2 diabetes)