Risk factor (medicine)
In medicine, a risk factor is an increased probability of acquiring a certain disease if certain physiological or anatomical properties, genetic predispositions or environmental constellations are present. The properties themselves are e.g. B. as a disposition (to an illness), the environmental influences as exposure , the frequency as a mathematical factor .
The concept of the risk factor is represented epidemiologically precisely by means of descriptive statistics . The characteristics of two groups are compared with the frequency of a certain disease. This resulting factor (expressed as odds ratio or relative risk ) indicates how many times more often a disease occurs with a certain characteristic or constellation compared to a control group . A risk factor greater than 1 means an increased risk compared to the control group, a risk factor between 0 and 1 means a reduced risk.
The statistically determined risk factor is not proof of an actual causal relationship between property and disease, since it represents a purely descriptive (descriptive) measure of an observed frequency. In this respect, the determination of risk factors can only give indications of a possible cause of a disease ( etiology ). However, he does not substantiate or explain them. The causal relationship is often known in diseases that carry an increased risk of developing a second disease. One speaks here of an underlying disease and the risk of a secondary disease (secondary disease ). A well-studied example is the increased risk for a diabetes mellitus , on a renal cancer.
Risk constellations that are frequently examined and taken up in the media are, for example, excessive alcohol consumption , obesity , diet , lack of exercise and tobacco smoking , which are associated with other changing risk factors for specific diseases. The term risk factor is used incorrectly here. Often an unproven or unprovable causal connection between an individual factor and a disease is assumed and this is (unscientific) presented as a risk factor. Often the property itself is incorrectly referred to as a risk factor and not the frequency, for example in phrases such as “Smoking is a risk factor for lung cancer”. It would be correct to say that smokers have a risk factor of 7.8 for developing bronchial carcinoma.
Some risk factors - such as B. chronic anger , which is an even stronger predictor of heart disease than z. B. high blood pressure - have been scientifically proven, but hardly play a role in social discourse.
See also
swell
- Wolfgang Ahrens, Iris Pigeot (Ed.): Handbook of Epidemiology . Springer, Berlin, 2005. ISBN 3-540-00566-8 (English)
- Lothar Kreienbrock, Siegfried Schach: Epidemiological Methods . Spectrum, Heidelberg, 2005 (4th edition). ISBN 3-8274-1528-4
Individual evidence
- ↑ Gail Ironson et al. a .: Effects on Anger on Left Ventricular Ejection Fraction in Coronary Artery Disease , The American Journal of Cardiology, Volume 70, 1992; Redford Williams: The Trusting Heart , New York: Times Books / Random House, 1989.