Risk factor
Say it: RISK FAK-tur
A risk factor is a trait, exposure or behavior linked to a higher chance of developing a particular disease, injury or other health problem.
Also: risk factors
Definition
What is a risk factor?
A risk factor is any characteristic, habit or exposure associated with an increased likelihood of a disease, injury or death. Risk factors are identified through epidemiological studies that compare how often an outcome occurs in people with and without the factor, and the strength of the link is usually expressed as a relative risk or odds ratio. Some risk factors are causes in their own right, while others are markers that travel with a cause.
They are often divided into fixed factors, such as age, sex, family history and inherited gene variants, and modifiable ones that people or policies can change. The World Health Organization highlights tobacco use, physical inactivity, unhealthy diets, harmful drinking of alcohol and air pollution as major modifiable risk factors for noncommunicable diseases, along with metabolic risk factors such as raised blood pressure, high blood glucose, high blood lipids and obesity. Some infections, radiation and workplace chemicals are risk factors for particular cancers.
Having a risk factor does not mean a person will develop the disease, and many people become ill without any known risk factor. The opposite is a protective factor, such as vaccination, which lowers the chance. Finding modifiable risk factors is the basis of prevention programs and of screening aimed at higher-risk groups.
Word parts
Where does the term “risk factor” come from?
- risk
- danger, hazardFrench risque, from Italian risco
- fact-
- to make, do (factor: a maker, doer)Latin facere
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Related
Terms that go with it
- Relative riskRelative risk is the risk of an outcome in an exposed group divided by the risk in an unexposed group, showing how strongly the two are linked.
- Odds ratioAn odds ratio is a measure of association that compares the odds of an outcome or exposure in one group with the odds in another group.
- Noncommunicable diseaseA noncommunicable disease is a long-lasting illness, such as heart disease, cancer or diabetes, that does not pass from one person to another.
- HypertensionHypertension is a long-term condition in which the pressure of blood against artery walls stays higher than normal, straining the heart and vessels.
- ObesityObesity is a chronic disease in which excess body fat builds up enough to harm health, defined in adults as a body mass index of 30 or more.
- Cohort studyA cohort study is an observational study that follows groups differing in an exposure over time to compare how often they develop an outcome.
Sources
Checked against
Written for biofideX in plain words, after checking these references:
- NCI Dictionary of Cancer Terms: risk factor
- NCBI MeSH: Risk Factors
- WHO Fact Sheet: Noncommunicable diseases
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