The Nutrition Debate #180: The AHA/ACC Cholesterol Guidelines

Last November, the American Heart Association and the American College of Cardiology (AHA/ACC) issued a new set of cholesterol guidelines that is proving to be as disruptive and discombobulating as the Affordable Care Act (Obamacare). In fact, it is so much so that Medscape Cardiology issued this Special Report titled, “CV Risk Calculator and Guidelines Controversy.” It has six separate links to “News” and six more to “Experts Weigh In.” That’s too much information for here.

So, succinctly put, what are the new cholesterol guidelines and what’s the stir all about?

The main recommendations are that individuals who fall into any of the following four categories should be on a statin:

1.       Those with existing heart disease.

2.       Those with LDL levels above 190mg/dL

3.       Those with diabetes aged 40 to 75 years with LDL between 70-189mg/dL and without existing heart disease.

4.       Those without heart disease or diabetes, with an LDL between 70-189mg/dL and as estimated 10-year heart attack risk of above 7.5%.

The above bullets and the following analysis were provided by Ronesh Sinha, MD, at his South Asian Health Solution site:

“When comparing the old guidelines to this one, the first 3 categories are essentially unchanged. Most doctors would put heart disease patients, diabetics and those with LDLs above 190 mg/dl on statins. There are some advantages to the newer guidelines:

·         The focus of therapy is on statins, which are the default drug of choice. This is a good thing for those who truly need statins and should hopefully avoid cumulative toxicity from multiple drugs.

·         The concept of treating to a specific LDL target number has been eliminated. This is good since it should reduce unnecessary high dose statin therapy to reach low targets which have not been proven to reduce heart attack risk.

·         These guidelines do a better job of highlighting statin adverse side effects which will hopefully make clinicians think twice before pulling the statin trigger.

·         Greater overall emphasis on heart attack risk rather than a focus on the LDL number which makes more sense.”

But it is Dr. Sinha’s (and many others) major criticism of the guidelines is “The 4^th category where individuals who have no risk factors other than a 10-year heart attack risk above 7.5%. This is significantly lower than the prior cutoff of 20% and will result in many more people taking statin medication.” Many more? That’s actually an understatement, in my opinion. I saw an interview of a healthy individual the other day on TV in which the doctor said to the 38-year old male, “In 2 years [when the patient achieved the threshold age of 40] you’ll be on a statin.” So, I decided to test the risk calculator myself.

The “risk factors” that are the sole basis of the 10-year heart attack risk are as follows: Sex, Age, Race, Total Cholesterol, HDL-Cholesterol, Systolic Blood Pressure, Treatment for High Blood Pressure, Diabetes, and Smoker. I plugged in my data and came up with a 10-year risk of atherosclerotic cardiovascular disease (ASCVD) is 28.1%, using the new calculator. Wow!

Then, I decided to see what I could do to lower my risk.  Age, sex, race were not things I could change. Neither could I improve my systolic blood pressure (110) or my diabetes (yes), treatment for hypertension (yes) or smoking status (no). And my HDL (85) was already outstanding. So, for me, that left only Total Cholesterol (TC). And since LDL-cholesterol is a calculated value (by the Friedewald formula), it is reduced (by a statin or otherwise) in direct proportion to TC. So, I decided to ‘prescribe’ a statin for myself to lower my TC (217) and thus LDL cholesterol by 50mg/dL to 167mg/dL, easily achieved on a statin. That would lower my LDL from 122 to 72, aligned to the “old” goal of 70. Result, my 10-year risk of ASCVD was reduced from 28.1% to 25.3%. The reduction was disappointing, to say the least. Hmmm…

What would happen if I lowered my age by 15 years to 57 (keeping the 217 TC)? The 10-year risk: 8.0%, just above the 7.5% cutoff. So, following these new guidelines literally (which I know no cardiologist would do, right?), I would be a candidate for a statin. No way, Jose, but I hope you see where I’m going. Dr. Sinha sums it up nicely in his “closer look” commentary:

“What’s missing? How about triglycerides, weight or waist circumference, prediabetic blood sugars, and physical activity levels? I have many patients, especially those of Indian and Asian background, who have high triglycerides, abdominal obesity and prediabetic blood sugars, but don’t smoke and have normal blood pressures. They have a condition called metabolic syndrome, caused by insulin resistance, which accounts for a huge burden of global heart disease and this calculator misses it in most cases. In fact, I’ve plugged in the “before” numbers for some of my heart attack patients and this magical calculator spit out a <1% risk of heart disease. Yes, a 60-year-old smoker with high blood pressure will register a high risk score, but you don’t need a medical degree or a risk calculator to figure that out.” What about cardiovascular fitness? Why do my 60+ year old lean, aerobically fit patients who eat a healthy diet continue to score as higher risk than my 40-year-old sedentary, obese, computer engineers who eat an unhealthy diet? I’ve already detected plaque and premature arthritis in these patients in their 30s and 40s, so in today’s high-tech world “age,” a key variable for the risk calculator, is much less critical than lifestyle and fitness levels.” Well said, doctor. Would that other clinicians did the same!

Next, I’ll take a “closer look” at the 3^rd category above, which seems to me to have escaped scrutiny in all the hullabaloo.