Cholesterol / HDL ratioTotal cholesterol to HDL ratio
Total cholesterol divided by HDL, a single figure used in risk scoring.
This ratio divides total cholesterol by HDL cholesterol. It compresses two numbers into one, on the reasoning that the same total means something different depending on how much of it is HDL.
It matters because it appears in cardiovascular risk calculators, which use it rather than total cholesterol alone. A lower ratio corresponds to a more favourable pattern in those models.
In practice it is a summary rather than a mechanism, and modern assessment increasingly favours markers that count the atherogenic particles directly, such as ApoB or non-HDL cholesterol.