Secondary prevention refers to the detection and management of presympto- matic disease, and the prevention of its progression to symptomatic disease. Screening is the dominant practice in this space, exemplified by cancer screening (., mammography, colonoscopy), and cardiac risk screening (., lipid testing, blood pressure screens). The margins between primary and secondary prevention can at times blur, depending on definitions used for diseases, their risks, and their antecedents. If hypertension is defined as a disease, its treatment is secondary prevention; if defined as a risk factor for coronary disease that does not yet exist, it is primary prevention. Presymptomatic diagnosis.
