Changing Units for Lipoprotein(a)

[Buckeye]

I had DH get his Lipoprotein(a) measured and the result was 41 nmol/L. I want to compare the result to the value given in "Beyond Cholesterol: 7 Life-Saving Heart Disease Test That Your Doctor May Not Give You" but the units in the book are mg/dL.

I googled a conversion program and calculated a value of 11.48 mg/dL. Does that sound right?

14 and below is considered "normal" according to the information in this book written by Dr. Julius Torelli, a board-certified cardiologist.

 

[Rich_by_the_Bay]

I've always used mg/dl and don't know the corresponding norms for nmol/L.

This begs the question of why it's being checked. For almost all patients, it adds no useful information; it doesn't respond to statins, adds additional (but not particularly practical) information only in specific circumstances (e.g. coronary disease or strong family history and no other identifiable lipid issues, hypertension and early organ damage, hypercholesterolemia resistant to treatment). Treating LP-a specifically has never been shown to improve outcomes. Often it's just an alternate explanation when nothing else is identified in patients who suffer a heart attack.

I'm not saying it's right or wrong in any specific case, but it's not something that helps very many patients.

 

[Buckeye]

Rich - He had it tested because we are looking at numbers other than cholesterol to help determine DH's risk of heart disease. Lp(a) was one of the "other" numbers mentioned in the book referenced in my initial post. He also checked his CRP (low at .4) and his homocysteine (a bit high at 12 so he is adding some B vitamins). He also takes an Omega 3 supplement.

DH's LDL runs high at around 190 so what does that mean in terms of risk given that he has normal BP, normal weight (32" waist), normal triglycerides, has never smoked, has pretty good HDL (55), no personal history of heart disease and lives a relatively stress free life as a stay-at-home hubby? He eats a pretty healthy diet that is low in saturated fat with a fair amount of fish, fruits and vegetables thrown in and he is moderately physically active. His primary care physician sees high LDL and wants to prescribe statins but nothing we read says that statins have been tested in people with "just" high LDL with no other risk factors (and DH wouldn't take them anyway).

The only person in his family who has/had any cardiac history is his father who drank like a fish and smoked like a chimney since his teens. He had a bypass in his late 60's (and continued to smoke) and died in his late 70's of an aortic aneurism. His mom is in virtually perfect health at 94 and she has high cholesterol. Her doctor talked her into taking statins for about a year but we convinced her to stop when she started to get forgetful and anxious. She stopped the Lipitor and quickly went back to her old (no pun intended) self.

We are still debating whether to do a scan to get a calcium score.

 

[Rich_by_the_Bay]

Naturally, only his own doctor can help with his personal decision on how to proceed. Lifestyle, age, and other factors beyond lipids weigh heavily in these kinds of choices.

Many of the tests you are discussing are of marginal prognostic value - you're down to fractions of a percentage point per year difference -- and have no proven value on outcomes under any treatment scenario, above and beyond the usual lifestyle and medication options.

You need to determine how much reassurance you need (at least some of it "false" reassurance - false negatives). Consider carefully the costs and eventually the risks (false positives) of all this testing. You'll never get the risk to zero. Basically, you are left with whether to treat his high-ish LDL, and that can be boiled down to numbers which his doctor can provide (e.g. risk of heart attack over the next 10 years with treatment and without treatment). No LP(a) result will negate that.

Just offering some food for thought to discuss with his doctor.

 

[Buckeye]

Rich - We're just putting all the information together and taking a look at the whole picture. Our doc is pretty focused on the LDL and he had no response when I asked him what the LDL level meant in the context of no other risk factors (other than age and sex). I told him I understood the statins would reduce DH's LDL but I would like him to provide data to show me whether the LDL reduction reduces the chance of a heart attack or sudden cardiac death in a person with my husband's profile. Show me the evidence upon which you are relying to make this expensive and possibly side-effect filled recommendation to someone who appears to be in very good health except for this one number. He said he would do some digging because he agreed he should be able to support his recommendation with data. Nothing yet.

There are just too many people with acceptable cholesterol levels having heart attacks (half the heart attacks from what I read). There are other things going on that, IMO, are not being discussed as much as they should be because of the stranglehold the statin makers have on the discussion.

I don't see any of the test results as tilting the meter "to everything's okay" or "you're going to die" next week. I will just continue to read and read and check different things out because there is much more to the story on cardiovascular health and cardiovascular disease than what I see in the Lipitor commercials on TV and what my doc is hearing from the drug salesman.

 

[Rich_by_the_Bay]

I've spent the better part of my academic career looking at research and interpreting results to aid medical decision-making. In my opinion it is typical of drug manufacturers to present data in such a way that it is misleading to both physicians and patients. I am not a fan of using drug companies as a source of scientific education, and I do not do so. Many do, alas.

Heart attacks are complicated and, yes, nearly half occur in patients with normal lipid levels. There are genetic components, inflammatory components, coagulation factors and likely many other facets to this. But to date, we don't know much about whether treating these other factors is really beneficial.

IMHO there is a place for the use of statins in many patients whose untreated risk of a heart attack starts to exceed 1% per year with lipids that are suboptimal. There are easy calculations to determine that risk based on population studies. Low dose aspirin does as much in that scenario, too, even with normal lipids. Individual lifestyle factors play in to the equation.

Only the patient can decide whether the risk of such treatment is outweighed by its benefits over the long term. In the end it's a trade-off without a right or wrong answer (though seemingly irrational decisions deserve a harder look and discussion).

Good luck in your quest for the right decision. I wish more of my patients had the same interest in prevention that you do.