Tag Archives: heart attack risk

Should You Get Tested For Lipoprotein(a), The “Hidden” Risk Factor For Cardiovascular Disease?

The skeptical cardiologist wrote about the importance of testing patients with premature atherosclerosis or strong family history of cardiovascular disease for Lipoprotein(a) here.

The National Lipid Association (NLA) published their scientific statement on Lipoprotein(a) (Lp(a)) (Use of Lipoprotein(a) in Clinical Practice: A Biomarker Whose Time Has Come) last summer (summarized nicely here) and I’ve listed their key recommendations below.

  1. For diagnosing high Lp(a) they chose a universal cut point of >100 nmol/L (approximately >50 mg/dl) which is at the 80th percentile in white Americans. This cut-off is not written in stone and may vary depending on risk, ethnicity, and comorbidities. Some labs report out Lp(a) in mg/dl, others in nmol/L. Pay attention to the units.
  2. An individual’s Lp(a) level is 80-90% genetically determined in an autosomal codominant inheritance pattern with full expression by 1-2 years of age and adult-like levels achieved by approximately 5 years of age. Outside of acute inflammatory states, the Lp(a) level remains stable through an individual’s lifetime regardless of lifestyle.

  3. High-quality evidence supports a link between Lp(a) levels and a variety of cardiovascular-related outcomes. See Table 1. The risk of heart attack and aortic stenosis is increased 3 to 4 fold.

Screen Shot 2020-02-16 at 7.12.39 AM

4. The following populations should be considered for testing.Screen Shot 2020-02-16 at 6.26.11 AM

5. Neither diet nor lifestyle influences Lp(a) levels.

6. PCSK9 inhibitor drugs and niacin lower Lp(a) levels and but there are no data showing this changes clinical outcomes.

7. Similar to my approach, “the authors recommend initiating a moderate- to high-intensity statin therapy in adults aged 40-75 years with a 10-year ASCVD risk of 7.5% to ≤20% with a Lp(a) ≥100 nmol/L. High-risk patients with LDL-C ≥70 mg/dL (non-HDL-C ≥100 mg/dL) and a Lp(a) ≥100 nmol/L on maximally tolerated statin should be considered for more intensive therapies (ezetimibe and PCSK9 inhibitors) to lower LDL-C.”

8. Currently, novel therapies are being studied that selectively target Lp(a). A phase 2 trial of AKCEA apo(a)-LRx, an apo(a) antisense oligonucleotide, reduced Lp(a) up to 80%. A phase 3 study is being planned. Additionally, an oxPL antibody that binds and inactivates the pro-osteogenic activity of Lp(a) has promising in vitro data. These therapies, while promising, require additional research prior to becoming mainstream therapies.

The cost of the blood test for Lp(a) should be minimal. Medicare reimburses $14 for it. You can order it from Boston Heart Diagnostics for $11. Unfortunately, there is no telling what your local hospital lab will charge.

Since Lp(a) is inherited, patients with high levels should consider having first-degree relatives tested for Lp(a) to identify those who are going to be at high risk. This provides an early warning of who in the family is most at risk for cardiovascular complications early in life. Such patients should be considered for early screening for subclinical atherosclerosis. In addition, they should be additionally motivated to do everything possible to reduce their elevated risk by lifestyle changes.

Proantiatherogenically Yours,

-ACP

N.B. In 2018 the Centers for Disease Control and Prevention (CDC) approved two ICD-10 codes for the diagnosis of elevated Lipoprotein(a), or Lp(a). The ICD-10 diagnosis codes help to identify asymptomatic patients with elevated Lipoprotein(a) (E78.41) and a family history of elevated Lipoprotein(a) (Z83.430)

N.B.2. Don’t confuse Lp(a) with Apolipoprotein A1 which is the major protein component of HDL particles in plasma. Also, please note that WordPress converted my little a into a capital A in the title and I have no idea how to prevent that conversion.

Donald Trump Has Moderate Plaque Buildup In His Coronary Arteries and his Risk For A Cardiac Event Is Seven Times Hilary Clinton’s Risk

Donald Trump recently appeared on the Dr. Oz show and handed a letter to the celebrity medical charlatan and TV host, Mehmet Oz.

The letter was written by his personal physician , Dr. Harold Bornstein,  screen-shot-2016-10-04-at-3-21-11-pm
and summarized various  laboratory and test  results which led Bornstein to conclude  that Mr. Trump is in excellent health (Bornstein did not repeat his earlier, bizarre statement that “If elected, Mr. Trump, I can state unequivocally, will be the healthiest individual ever elected to the presidency.”)

From a cardiovascular standpoint the following sentence stood out:

“His calcium score in 2013 was 98.”

Regular readers of the skeptical cardiologist should be familiar with the coronary calcium scan or score (CAC) by now.  I’ve written about it a lot (here, here, and here) and use it frequently in my patients, advocating its use to help better assess certain  patient’s risk of sudden death and heart attacks.

coronary calcium
Image from a patient with a large amount of calcium in the widowmaker or LAD coronary artery (LAD CA).

The CAC scan utilizes computed tomography (CT)  X-rays, without the need for intravenous contrast, to generate a three-dimensional picture of the heart. Because calcium is very apparent on CT scans, and because we can visualize the arteries on the surface of the heart that supply blood to the heart (the coronary arteries), the CAC scan can detect and quantify calcium in the coronary arteries with great accuracy and reproducibility.

Calcium only develops in the coronary arteries when there is atherosclerotic plaque. The more plaque in the arteries, the more calcium. Thus, the more calcium, the more plaque and the greater the risk of heart attack and death from heart attack.

What Does Donald’s Trump’s Calcium Score Tell Us About His Risk Of A Major Cardiac Event?

We know that, on average, even if you take a statin drug (Trump is taking rosuvastatin or Crestor), the calcium score goes up at least 10% per year which means that 3 years after that 98 score we would predict Trump’s calcium score to be around 120.

Based on large, observational studies of asymptomatic patients, Calcium scores of 101 to 400 put a patient in the moderately high risk category for cardiovascular events.

When I read a calcium score of 101-400, I make the following statements (based on the most widely utilized reference from Rumberger

This patient has:

-Definite, at least moderate atherosclerotic plaque burden

-Non-obstructive CAD (coronary artery disease) highly likely, although obstructive disease possible

-Implications for cardiovascular risk: Moderately High

Patients in this category have a 7-fold risk of major  cardiac events (heart attack or death from coronary heart disease) compared to an individual with a zero calcium scorescreen-shot-2016-10-04-at-3-16-25-pm

 

 

Clinton versus Trump: Zero is Better

Since we know that Hillary Clinton recently had a calcium scan with a score of zero, we can estimate that Trump’s risk of having a heart attack or dying from a cardiac event is markedly  higher than Clinton’s.

Clinton, born October 26, 1947 is 68 years old and we can enter her calcium score into the MESA calcium calculator to see how she compares to other women her age. A  coronary calcium score of 6 is at the 50th percentile for this group.

Interestingly, Trump’s score of 98 at age 67 years was exactly at the 50th percentile. In other words half of all white men age 67 years are below 98 and half are above 98, creeping into the moderately high risk  category.

(This should not be surprising, I touched on the high estimated cardiovascular risk of all aging men in my post entitled “Should all men over age sixty take a statin drug?”)

So, based on his coronary calcium score from 2013, Donald Trump has a  moderate build up of atherosclerotic plaque in his coronary arteries and is at a seven-fold higher risk of a cardiac event compared to Hilary Clinton.

Let the law suits and tweets begin!

Electorally Yours,

-ACP