A Tale of Two Lipid Panels

Awhile ago, TheFatNurse noticed something strange while reviewing some Lipid panels. Normally, when you receive a lab result, a reference range is given and any numbers above or below the reference range is flagged. What was strange about some of these lipid panels was the lack of flags for patient numbers that were clearly in the high risk range. For example, Let’s take a hypothetical patient:

Total Cholesterol: 165
HDL: 35
LDL: 105
Triglycerides: 244

If you’ve read through the critique of LDL Cholesterol as an indicator of risk you’ll know that LDL cholesterol can sometimes be inaccurate in gauging heart disease risk. However, that is a different problem all together (addressed later in the post) and for the purposes of this post let’s just use the standard numbers provided by the ATP-III clinical guidelines:

So according to the clinical guidelines, this patient’s total cholesterol would be classified as “desirable,” his HDL cholesterol would be “low,” his LDL cholesterol  is pretty much at “optimal,” and his triglycerides are “High.” Therefore, on a lipid panel  you may assume that his Triglycerides and HDL will be flagged. However, depending on what reference ranges a lab uses, this can differ. Here are two example:

ReferenceRange1

This patient is within “range” according to this reference

ReferenceRange2

This patient is not within “range” according to this reference

Before going on, it should be made clear that one should never make the mistake of thinking a reference range is the same thing as target goals (which change according to an individual’s risk category) for a patient. A reference range is simply the distribution of values that are seen in the folks of a given population. However, patients can make the mistake of comparing their numbers to the reference range (and sadly sometimes even clinicians make this mistake) and therefore think they are at low risk when the opposite is really true.

In the first panel, the numbers from our hypothetical patient would not be flagged and a person may think they are at low risk. In the second panel, the numbers from HDL and Triglyceride would be flagged as abnormal. Therefore, it’s more important to go by target goals rather than what a lab supplies as a reference range. As a side note, the advance lipid panels such as the NMR, VAP, and Ion Mobility advance lipoprotein tests, suggest a reference range for triglycerides at <150 mg/dL. The reference range supplied by the first lab at <250 is obviously way too high to be viewed as a target goal and should never be viewed as such.

However, as mentioned in a previous post, even reaching the target goals of LDL cholesterol can be inaccurate to risk. This is even mentioned in the ATP-III where it is suggested to use Non-HDL cholesterol as a target goal if triglycerides are above 200 like our hypothetical patient. However,  Non-HDL isn’t always supplied in a lipid panel and many clinicians do not understand its purpose nor do they know how to calculate it even if they wanted to use it. The same dilemma holds true for looking at the TG/HDL ratio as well. In this scenario, our hypothetical patient’s TG/HDL ratio of 6.97 indicates a high likely hood of increased small and total LDL particles which means he’s at risk for atherosclerosis despite being at target for his LDL cholesterol. If we could advance test everyone with LDL particle testing that could solve a lot of confusion but that would be very expensive  and it’s not always an appropriate test if the regular lipid panel is concordant. With this in mind and everything else we’ve discussed so far on reference ranges and target goals, it’s not hard to imagine a situation where the interpretation of risk between the patient and the clinician and another clinician is vastly different between each party.

TL:DR; Different labs provide different reference ranges which are not the same as target goals. Some of the supplied reference ranges can be vastly outside what would typically be considered a target goal. This can lead to different interpretations of a lipid panel where risk may be judged inaccurately.

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Showing HDL The O Face

Actually it’s more like “OMG my chest hurts so bad!” instead of the above clip from Office Space, but…some people do get symptoms of Acute Coronary Syndrome (ACS) from doing “O Face” type “activities.” What is TheFatNurse reffering to? A new study showing some associations between Apolipoprotein O levels and ACS.

Apo O is a novel lipoprotein found in mostly HDL and researchers are still trying to figure out its role in the body. In the meantime, the new study found associations of increased Apo O levels and people with ACS compared to normal subjects. This was found independent of other lipid markers. So what does this mean? It’s too soon to tell, but this study can be useful for generating further hypothesizes. Perhaps it can be a cardiac marker in the future? Apo O will certainly be something interesting to follow as the research on it continues.

Regardless, this was probably the first study TheFatNurse read that made TheFatNurse extremely hungry…I mean look at this sentence!

ApoO was measured by the sandwich dot-blot technique with recombinant apoO as a protein standard.

Yes TheFatNurse knows they are not talking about food but it makes TheFAtNurse think of:

HDL for all ages!

HDL cholesterol is often touted as a super stud in heart disease prevention. As a result, common knowledge has continually stressed increasing one’s HDL cholesterol without really moving beyond the “HDL Good LDL Bad” message. This belief can target researchers as well, but some recent studies, as covered by Peter Attia, reveal HDL cholesterol and heart disease not being as clear cut as one might believe.

As a result, TheFatNurse thought it would be a good idea to go over some simple basics about what exactly HDL is and does in your body through a comic. This comic is based on a series of lectures by Dr. Thomas Dayspring and is only a simplified version of his more detailed analysis. See below if you’re itching to read Dr. Daysprings more detailed lectures!

TheFatNurse also wants to extend a personal thank you to Dr. Dayspring. TheFatNurse is still beginning his journey in exploring all things lipid and Dr. Dayspring your encouragement, feedback and information have made exploration exciting.

Before reading, TheFatNurse recommends you read the first two comics on cholesterol as it builds upon some knowledge needed for this third comic. Click here to read the HDL comic (semi-long read!) or the picture below.

***For the first two comics see: #1 Cholesterol For All Ages and #2 Cardiovascular Markers For All Ages. Interested in more? TheFatNurse highly recommends you look up Dr. Dayspring’s lectures on HDL which you can start with here and here.

HDL Not Useful Anymore? Maybe the Whole Lipid Profile is Useless

So the New York Times dropped a stunner to the world this week with an article that called into question how useful HDL really is. Lots of TheFatNurse’s fellow peers were shocked by it. Is this really new tho? Or has the community just been looking at HDL cholesterol in the wrong manner? Indeed, just earlier in the month another study showed HDL being harmful depending on whether the HDL has a apoC-III protein on it. In a manner similar to the discovery of Dr. Krauss that not all LDLs are alike, not all HDLs are alike either.

Dr. Thomas Dayspring, a lipidologist, has been saying all along that the standard LipidProfile test that you get done at the doctor’s office is outdated and may not accurately predict atherogenic risk. I know I know this is probably your reaction:

Just hear TheFatNurse out!

However, with the exception of Non-HDL (Total cholesterol- HDL cholesterol) and triglyerides/HDL to get a “poor man’s insulin resistance” (ratio of 3 or above = likely insulin resistance)” the other values on the standard lipid profile may not be as useful. Yes even the LDL cholesterol (insert another GTFO pic!). Instead, getting a test to see the size and number of particles in LDL may be a better predictor of atherogenic risk.

What is this particle nonsense you say? It’s the view that risk is not dependent on total LDL cholesterol but the way LDL cholesterol is carried through the number and size of LDL particles (Some evidence is showing that the size is of lesser importance than previously believed and it’s the number of LDL particles themselves that are important). The more particles the higher the risk (driven by insulin resistance). Dayspring believes a number below 1000 nmol/L would be ideal and a number above 1600 nmol/L is the start of high risk. If you find this intriguing, the video below features Dr. Dayspring talking about all of this along with a case study to follow along with:

The Bottom Line: The New York Times article is a good starting point for people to reevaluate and redefine what cholesterol is. Much of the cholesterol knowledge that is taught in schools and to the public is outdated and there have been newer theories and tests developed that are much better than the traditional “HDL = good LDL = bad” advice. Are these newer theories right? Maybe, maybe not, but they should certainly be discussed more often than the same old archaic advice which is often treated as medical fact rather than theory.