Old Cholesterol Guideline Theme: It’s All About Your LDL Number
When clinical guidelines come out, there are two major levels at which they’re interpreted. The first interpretation is literal, following the guidelines to a tee. However the more important interpretation is the guideline theme. Most docs forget about the specific details over time and apply the general message to their practice. The prior cholesterol guidelines morphed into the following thematic messages:
New Cholesterol Guideline Theme: It’s All About Your Heart Attack Risk
4. Those without heart disease or diabetes, with an LDL between 70-189 mg/dL and an estimated 10-year heart attack risk of above 7.5%
- 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.
What is the major drawback of these guidelines?
The 4th 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 medications. My biggest pet peeve with this category is the risk calculator which in my experience is a terrible tool. It’s based on the Framingham Heart Study. Unless you are white, live in Framingham, Massachusetts, and have recreated a 1950s lifestyle, maybe this risk calculator would have some value in estimating heart attack risk. However for the rest of us, it is a pretty useless tool. The data entry points are gender, age, race (you’re either African American or not), total cholesterol, HDL (good cholesterol), systolic blood pressure (top number of your blood pressure), diabetes status, and smoking status.
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.
Be Skeptical About Guidelines