Blood Work

[PFerrari]

Hey Jordan, just got some blood work done. Total cholesterol was 221, HDL was 49, LDL was 161, triglycerides were 56. From what I understand, given high HDL and low triglycerides I don't really need to be concerned about the elevated LDL since it's likely the fluffy kind. Have you read anything else similar or different?

[Jordan Feigenbaum]

Eh, I can't really hang my hat on just the particle size and high HDL being big predictors of an absence of heart disease. Emerging research and analysis tends to predict heart disease with more accuracy when total amount of LDL (LDL particle concentration) is measured, not just the size, total cholesterol content, etc. I believe the test is an NMR analysis and only a handful of labs are FDA approved to do such testing.

Just as a quick example, persons with familial hypercholesterolemia tend to have a high LDL particle concentration and most of them are large and fluffy kinds (type A), but they have a much higher risk of atherosclerosis and related disease because of the overall increase in LDL number compared to age and sex matched controls.

[LimieJosh]

Agreed. The more i read the more i conclude that the strength of LDL particle size as a predictor comes from it being a good surrogate for LDL number when used in addition to LDLc.

I would also not call and HDL of 49 "high".

[Jordan Feigenbaum]

Agree, especially for a male.

[Brodie Butland]

For the medically-inclined on here, what exactly is your understanding of the relationship between HDL, LDL, and triglycerides as they pertain to heart disease?

So far, I've seen no fewer than four proposed metrics that supposedly can accurately predict the future risk of heart disease:
--HDL to LDL ratio
--HDL to tris ratio
--LDL levels in and of themselves
--tri levels in and of themselves

I'm assuming that total cholesterol has basically been recognized as obsolete by the medical establishment.

[Jordan Feigenbaum]

In a nut shell, the all tell you something, however individually the only really useful one (at the moment) for predicting anything is the LDL particle concentration when it comes to heart disease. Other diseases however, might find some utility in the other metrics, but I'm not privy to that information yet.

[Brodie Butland]

Thanks for the reply J Feig. So basically, high LDL is bad is the takeaway of the research?

[Jordan Feigenbaum]

Thanks for the reply J Feig. So basically, high LDL is bad is the takeaway of the research?

High LDL particle concentration in the blood seems to be the strongest predictor of heart disease, yes. However, it's really hard to just say high LDL is bad and further, what is the critical threshold for when LDL particle concentration becomes too high. There are also benefits of having higher LDL, i.e. immune system function. I also want to make crystal clear we're not talking about LDL cholesterol, which is what typically gets measured when people go to the doctor, but rather LDL particle levels in the blood themselves (the actual amount of lipoproteins not the cholesterol).

[LimieJosh]

Even worse, LDLc is rarely actually even measured, but calculated based on the measured values for total, HDL and TGs. Our cost for ordering an actual measurement is about 10 times higher than that for a normal lipid panel, and even that only gives you the LDLc and average particle characteristics, not the particle number, which really seems to be the most important.

[Jordan Feigenbaum]

Even worse, LDLc is rarely actually even measured, but calculated based on the measured values for total, HDL and TGs. Our cost for ordering an actual measurement is about 10 times higher than that for a normal lipid panel, and even that only gives you the LDLc and average particle characteristics, not the particle number, which really seems to be the most important.

Yes. IIRC only a handful of labs are doing the NMR tests for LDLc and only one is FDA approved for insurance purposes.