What Your Triglycerides Level Means

[Eddy Edson]

Another useful piece from Gil Cavalho. He does a good job of relating mainstream science & recent findings to tropes on social media; includes lots of references in the video descriptions.

This piece is centered on a recent fibrate trial: https://www.nejm.org/doi/full/10.1056/NEJMoa2210645

Fibrates were a hopeful CV class back in the olden days, because they lower trigs and increase HDL. But then trials showed minimal actual CV risk reduction, so for most purposes (apart from very high trigs) they are now deprecated.

This trial was kind of a last-gasp fibrate effort, with a new more powerful drug. Maybe we finally get a risk reduction signal? But no: big reduction in trigs, modest increase in HDL, but sod-all CV risk reduction. The reason: apoB actually increased a bit, and apoB is actually what researchers care most about these days. Every atherogenic particle includes an apoB molecule; counting apoB counts the number of risky particles. It's a direct measure of causal factors, not just a marker.

In more detail: HDL doesn't carry an apoB molecule; triglycerides do but they are a minority of atherogenic particles, and in addition, it seems like the mechanism of this drug is to convert them into more LDL particles. So no reduction in apoB counts.

For most purposes, trigs and HDL are markers, not causal: making them "better" will achieve little if underlying causes aren't addressed. If you increase LDL & therefore apoB counts, it doesn't really matter much what trigs and HDL are doing. So trigs/HDL, TC/HDL etc etc "ratios" aren't useful for much except for maybe giving an indication at baseline for possible causes of dyslipidemia.

Personally, I'm on fenofibrate for its potential benefits in slowing retinopathy progression, with a poorly-understood mechanism not related to lipids. Impact in line with expectations: trigs went from 0.7 -> 0.5, HDL 1.1 -> 1.3. Fans of ratios would say that because my trigs/HDL ratio improved my CV risks will have reduced. But the best research seems to say that's unlikely, unless my apoB count also reduced.

At some point apoB counts will become part of the standard lipid panel, I reckon, just based on the views of the major international expert bodies, which say that they should. Apparently it's a simple cheap direct measure. Will be interesting to see what the NICE lipid management guidelines say when they are updated next year.

What the NICE and NHS guidelines do say at the moment is that the key metric for CV risk on the current lipid panel is non-HDL cholesterol. This is a reasonable proxy for apoB, except when there's "discordance" - in other words, except when it isn't 🙂

At least here in Oz, no metric ever seems to get thrown off the bus. Non-HDL-C made it on to my lipid panel a year or so ago, but it still retains the largely useless total cholesterol and TC/HDLratio metrics, with guideline ranges for all of these which are likely inconsistent with each other. Far more confusion for the patient than is necessary, and an invitation to cherry pick metrics as prompted by eg social media.

Eg" "My LDL is high but my ratios are 'within range' so everything is peachy" etc etc. Nope, sorry.

 

[everydayupsanddowns]

At some point apoB counts will become part of the standard lipid panel, I reckon, just based on the views of the major international expert bodies, which say that they should. Apparently it's a simple cheap direct measure. Will be interesting to see what the NICE lipid management guidelines say when they are updated next year.

What the NICE and NHS guidelines do say at the moment is that the key metric for CV risk on the current lipid panel is non-HDL cholesterol. This is a reasonable proxy for apoB, except when there's "discordance" - in other words, except when it isn't 🙂

I think that would be a very helpful change.

LDL is only ever estimated in the UK (usually via Friedewald).

Actually being able to monitor via measured ApoB, and then seeing CV outcomes across a broad population (with very different glucose profiles / disease duration in the case of PWD) would be hugely helpful to the debate I think.

 

[Robin]

I think that would be a very helpful change.

LDL is only ever estimated in the UK (usually via Friedewald).

Actually being able to monitor via measured ApoB, and then seeing CV outcomes across a broad population (with very different glucose profiles / disease duration in the case of PWD) would be hugely helpful to the debate I think.

When I had my bloods done for the hospital back in August, they sent coded labels to my surgery, and the nurse duly took the bloods and stuck the labels on, saying she’d no idea what they were all for.

When I got the results, I noticed one of them was 'Apolipoprotein B level, blood' and the result was 0.69 g/L. Is this what’s meant by Apo B? It’s the first time it’s ever appeared on my blood results.

I never discussed them with the hospital afterwards, because they were ordered after my telephone appointment , then reviewed by the clinic and came back just with the raw scores and a 'No problem items recorded' message at the top of the letter.

 

[Eddy Edson]

When I had my bloods done for the hospital back in August, they sent coded labels to my surgery, and the nurse duly took the bloods and stuck the labels on, saying she’d no idea what they were all for.

When I got the results, I noticed one of them was 'Apolipoprotein B level, blood' and the result was 0.69 g/L. Is this what’s meant by Apo B? It’s the first time it’s ever appeared on my blood results.

I never discussed them with the hospital afterwards, because they were ordered after my telephone appointment , then reviewed by the clinic and came back just with the raw scores and a 'No problem items recorded' message at the top of the letter.

Yes, that's apoB. 0.69 g/L = 69 mg/dL, below the general cut point of 80 mg/dL above which you are generally thought to be steadily accumulating risk.

So if you don't already have CV issues, all good.

If you're more of a secondary case, like me, then you want to get it as low as possible. Somewhere in the 30's is a level I see quoted by various lipid experts.

 

[Robin]

Yes, that's apoB. 0.69 g/L = 69 mg/dL, below the general cut point of 80 mg/dL above which you are generally thought to be steadily accumulating risk.

So if you don't already have CV issues, all good.

If you're more of a secondary case, like me, then you want to get it as low as possible. Somewhere in the 30's is a level I see quoted by various lipid experts.

Thank you, @Eddy Edson . No CVD or fam hist of it, touch wood.

 

[nonethewiser]

Never heard it mentioned in own results, interesting Eddie nonetheless.