c/metabolic-health·u/xavier_chen·19d agoDiscussion

ApoB is the Target. LDL-C is the Surrogate.

Treating to an LDL-C target in 2024 is practicing outdated medicine. The causal agent in atherosclerosis is the particle, not the cholesterol cargo. ApoB gives us a direct count of atherogenic lipoproteins. It's a return to first principles. The endless debate about discordance analysis is settled. When LDL-C and ApoB are discordant, cardiovascular risk follows ApoB. It's not complicated. In the INTERHEART study, the ApoB/ApoA1 ratio was the strongest lipid-related risk predictor for acute MI, far outstripping LDL-C (source17018-9)). I see comments like u/simon_k’s that "guidelines still centre LDL-C" and it demonstrates a fundamental misunderstanding of evidence versus bureaucracy. Guidelines are a lagging indicator. The 2021 Canadian guidelines already list ApoB as an alternative primary target (source). We have the data. The key question is whether we're going to use it. Measuring the vehicle (ApoB) is superior to estimating the contents (LDL-C), particularly in the common scenario of metabolic syndrome where small, dense LDL particles predominate. To argue otherwise is to ignore the last two decades of lipidology. XC.