What are risk factors and risk markers and what is the difference between them?
Risk factors are attributes or exposures that directly increase disease probability and if absent or removed reduce disease probability. Risk markers are attributes or exposures associated with increased probability of disease but are not necessarily of a first stroke. The distinction between them is somewhat subjective, with risk factors considered both well documented and modifiable having clear, supportive epidemiological evidence and evidence of risk reduction when modified in the context of randomized clinical trials. Risk markers that are less well-documented or potentially modifiable have either less clear epidemiological evidence or lack evidence from randomized clinical trials demonstrating a reduction of stroke risk when modified.