I am getting confused with the A and B lipids. My doctor ordered this test for my husband along with hs C-Reactive Protein and Homocysteine. The last two we wanted but we also suggested a lipoprotein(a) test. He added that to the list. What is the Apolipoprotein B test? I did a search and found that it measures Apo B-100 which can be a cardiac risk. I though that lipoprotein(a) was the bad one and in an A/B ratio, it was good to be toward pattern A. I hope someone can make this clear.

Jacqueline,

All I know about apolipoprotein A & B is that they are carrier molecules for cholesterol. The Apo B is the carrier molecule for LDL, and the Apo A is the carrier molecule for the HDL. At least, that's my understanding of it. Lipoprotein(a) is something else. It's a plasma protein with a structure and composition that closely resembles those of LDL, but with an additional molecule of an adhesive protein. Perhaps someone else can contribute some additional information about this.

I am getting confused with the A and B lipids. My doctor ordered this test for my husband along with hs C-Reactive Protein and Homocysteine. The last two we wanted but we also suggested a lipoprotein(a) test. He added that to the list. What is the Apolipoprotein B test? I did a search and found that it measures Apo B-100 which can be a cardiac risk. I though that lipoprotein(a) was the bad one and in an A/B ratio, it was good to be toward pattern A. I hope someone can make this clear.


Arizona did a great job of explaining it. It depends on how deep you really want to go, but basically, think of Apo A (mainly Apo A-I) as an alternative measure to HDL and Apo B-100 as an alternative to LDL. Really though, the Apo B-100 also is a primary protein component of VLDL, which are your triglyceride carriers. There are breakdown percentages of these Apolipoproteins for HDL, LDL, and VLDL, and if you really want to know them I can post them. To be honest, its probably just to leave it as the relationships Arizona described.

Now, Lp(a) is made in the liver, and its similar to LDL (Apo B-100 is the primary protein and its linked by a -S-S- bridge to Apo(a)).

OK now back to your A/B pattern types. Are you sure in this case that your physician wasn't referring to particle sizes as type A and type B? In that case, A and B aren't related to the Apo-A and Apo-B described above. It sounds like your husband is having an NMR lipoprofile analysis and in that case you will get information on the particle sizes (type A, which is low risk particle size 20.6-22 vs. B, higher risk, <20.6 nm) and still get the LDL, HDL and VLDL concentrations in the plasma. The additional tests that can be ordered are hs-CRP, homocysteine, and Lp(a), as you mentioned in your post.

I have an some results from NMR lipoprofiles in a post made a while ago (sorry about the columns not lining up well anymore, but the lipoprofiles are in the 2nd post):
http://www.healthboards.com/boards/showthread.php?t=61608

Thanks to both of you for the great explanations. I will have to mull them over for a while. Maybe more than I wanted to know, but it is becoming clearer.

Ubernier

I've been looking at your lipoprofile and trying to associate the results I got on my recent VAP test. There were a lot of subclasses on the second page of it that didn't mean much to me. Maybe you can make sense of them.

Dense HDL 3d 10.9, 3c 12.0, 3b 5.8, 3a 14 Total 43 (less protective)

Buoyant HDL 2a 8.2, 2b 1.2, 2c 2.3 Total 12 (more protective)

Lp(a)4 9.3 Lp(a)1 4.4 The other 3 subclasses were 0. Total Lp(a)=14

Real LDL LDL4 14.3 LDL3 45.3 These 2 represent pattern B (bad)

LDL2 21.8 LDL1 8.1 pattern A (good)

IDL2 4.4 IDL1 2.5

VLDL 3b 2.2 VLDL 3b 1.6 VLDL 1+2 3.5

Apoprotein B-100 ias located in each of these subclass particles- LDL, Lp(a), IDL, and VLDL in a ratio of one Apoprotein B-100 molecule per particle.

Ubernier

I've been looking at your lipoprofile and trying to associate the results I got on my recent VAP test. There were a lot of subclasses on the second page of it that didn't mean much to me. Maybe you can make sense of them.

Dense HDL 3d 10.9, 3c 12.0, 3b 5.8, 3a 14 Total 43 (less protective)

Buoyant HDL 2a 8.2, 2b 1.2, 2c 2.3 Total 12 (more protective)

Lp(a)4 9.3 Lp(a)1 4.4 The other 3 subclasses were 0. Total Lp(a)=14

Real LDL LDL4 14.3 LDL3 45.3 These 2 represent pattern B (bad)

LDL2 21.8 LDL1 8.1 pattern A (good)

IDL2 4.4 IDL1 2.5

VLDL 3b 2.2 VLDL 3b 1.6 VLDL 1+2 3.5

Apoprotein B-100 ias located in each of these subclass particles- LDL, Lp(a), IDL, and VLDL in a ratio of one Apoprotein B-100 molecule per particle.

Hi Jacqueline:

Lets see where to begin (the VAP is similar to an NMR lipoprofile):

They have fractionated the HDL into two types, the non-beneficial dense HDL, and the buoyant beneficial form. Your total HDL is 55, of which 12 is the better form, 43 is the more dense form. I too started off with almost all my HDL as dense. Exercise and weight loss brought it such that most of my HDL is now buoyant. Niacin will do that also ;) Exercise has done wonders with respect to changing my LDL from dense to more buoyant also.

Your total LDL will be a sum of Lp(a)+derived real LDL fractions+IDL= ~110 from my calculations. If Lp(a)>25, you are at increased risk for MIs.

The VLDL and IDL are related to triglycerides, and since your VLDL3 is <10, you are probably fine here.

So to recap, HDL2 are the protective types, HDL3 are less so; LDL1 and LDL2 are less a risk factor than LDL3, LDL4, Lp(a), IDL1 and IDL2. VLDL+IDL correlate to your triglyceride level.

You might be (just barely) in the high LDL category, based on my calcs--I could be off though :) Exercise and/or niacin will do a significant level of shifting your dense particles to buoyant if you can increase or add either of those.

Ubernier, thanks, I appreciate that. I hope my doctor has a better grasp on this than I do.

I am somewhat disappointed in the lab reports we received. The CRP and homocysteine tests were clear and in a good range, but I am puzzled about the rest. I swear I looked at the prescription form to see that lipoprotein(a) was ordered and also copied off the apolipoprotein B test spelling for this post to find out what it was. The results we got had no lipoprotein(a). The only other result we had was a direct measurement of LDL, for which there was no need (and which I understand is fairly expensive).

We got a copy of the prescription from the hospital lab and were surprised to see Apoprotein (B) level + (a) as one of the tests to be run (sent out to another lab). Any idea what this means? Does it possibly correlate with the direct measurement of LDL? We were expecting a listing of the subclasses of LDL.

The hospital ran hepatic and lipid panels and I noticed on the hospital lab report the three tests they sent out:

CRP
Homocystine
Lipoprot ELP (assume this is lipoprotein electrophoresis, which according to the NIH is direct measurement done to determine LDL)

But what the devil is Apoprotein (B) level + (a)?

:confused:

Jacqueline:

Beyond what I told you, I am not familiar with the test as your wrote it. I assumed, as you did, that the Apo B was to get some idea about your true LDL, well LDL + VLDL in essence, while the Lp(a) was to examine another risk factor.

At this stage, your best answer may come from asking your physician these questions. I guess we are only guessing right now, based on what was on that prescription....

I don't think anyone is familiar with the test as written. I have a friend who is a lab technician and runs tests. He said it was confusing and if he was running the tests, he would have to call the doctor. We left some written questions at the doctor's office and the only reply was to call the lab. My husband is really annoyed and ready to drop the doctor. He will talk to the hospital lab first to see how it got converted to a Lipoprotein ELP. I think I am losing confidence in the labs and maybe the doctor too.