The importance of lipid tests in today’s physician office lab.
Advancements in the diagnosis and treatment of diseases often associated with advanced laboratory assays have come with such incredible speed that we sometimes forget the basic tests, the ones that underpin everyday diagnosis and treatment of patients to diagnose and treat the 10 leading causes of morbidity and mortality.
Lipid tests – total cholesterol, HDL, LDL cholesterol and triglycerides – often fall into this category. As a reminder, elevated lipid levels are directly associated with 3 of the 10 leading causes of death: heart disease, stroke and kidney disease. In addition, in combination with other factors, they are also associated with diabetes. In total, they account for diseases associated with 40% of ALL the leading causes of morbidity and mortality in the United States today.
Is it any wonder that diagnosis and treatment of patients with elevated lipids is a major focus for primary care health practices across the U.S.?
Suppose for a minute that we could be more effective in diagnosis and subsequent management of patients with lipid disorders. That advancement would have a profound impact on both life expectancy and quality of life. How would it impact your customers? In this column, I am going to review the basics surrounding lipid disorders as well as the most common lab tests that can quickly and effectively diagnose and monitor lipid disorders. As I have mentioned previously, “the primary reason to perform a test at the point of care is whether it can be used to initiate or modify a patient treatment program.” There is no doubt in my mind that lipid disorders fall directly into this category of healthcare concerns. Let’s review some facts together to understand the importance of lipid testing and patient management of lipid disorders.
Cholesterol and triglycerides are produced by the body and are critical to health (and disease)
As part of our understanding of the dynamics of lipid metabolism, we sometimes miss the obvious: cholesterol is produced by the liver and is the key building block of “steroid hormones” such as estrogen, cortisol and testosterone. HDL cholesterol is also naturally occurring and acts as a transfer protein to scavenge cholesterol from the bloodstream and return it to the liver to be removed from the body. LDL is also synthesized by the liver. Triglycerides are produced by the liver and occur in many of the foods we eat. They are used to store calories for later use. It goes without saying that these lipids are essential to life, but that the difference between health and lipid disorders results from the amount of these lipids in our body.
There are “know your numbers” campaigns regarding blood pressure, glucose and lipids conducted routinely across the country. Some are conducted locally and others in association with health advocacy groups. You would be well advised to find these programs locally and offer your support.
The generally accepted “numbers” for lipids follow:
Cholesterol (lower is better)
Desirable: less than 200 mg/dl
Borderline: 201-240
High: 240 or greater
HDL cholesterol (higher is better)
60 mg/dl or higher is desirable
41-59 mg/dl is “ok”
Below 40 is undesirable
LDL cholesterol: lower is better
Less than 100 is desirable
100-129 is slightly elevated
130-159 is borderline high
160-189 is high
Greater than 190 is very high
Triglycerides: lower is better
150 mg/dl or lower is desirable (physicians tailor the level to lower values for at risk patients)
151-200 mg/dl is moderate risk
Greater than 200 mg/dl is high risk
Individual patient age and risk factors are also taken into account when physicians tailor specific lipid goals to each patient, which is another reason for testing at the point of care where the entire patient presentation can go into a comprehensive treatment program including lipid management, vital signs measurements and lifestyle modifications.
How well established is the evidence of linkage of elevated lipids associated with cardiac risk?
If any data on overall heart disease risk factors can be considered “bulletproof,” there is no question that all the needed evidence for lipid management has been compiled, continues to be published and analyzed, and that recommendations for lifestyle modification (blood pressure control, healthy diet, exercise and cessation of smoking) have been published by multiple clinical authorities. The pivotal first study, the Framingham Study, began in 1948 and established the risk factor criteria for heart disease for the first time in a single comprehensive study. It initially enrolled over 5,000 men in their middle years. In 1971, a second generation of over 5,000 study participants was enrolled, and incredibly in 2002, a third generation of participants was enrolled. Arguably, the Framingham Study is one of the longest lasting longitudinal studies of heart disease from all causative factors.
The list of subsequent studies confirming the validity of the Framingham study is too exhaustive to list, but the Multiple Risk Factor Intervention Trial (MR-FIT ) which ran from 1972 through 1998 and enrolled over 12,000 participants is another well-known and often cited reference in this area. This study focused on reduction in saturated fats in diet, reduction in cigarette smoking and control of blood pressure. The study concluded that the “special intervention” group that sought to control these risk factors compared to the control group that did not have significant reductions in heart disease and heart attack. These findings, and the recommendations of an array of well-established clinical authorities including the National Institutes of Health, American Heart Association, and the US Preventive Services Task Force have clearly supported and published these findings in both peer reviewed and general publications.
Your clinician customers have been extensively trained to counsel their patients on lifestyle improvements and to routinely check both blood pressure and lipid levels. Remarkably, while blood pressure testing is an established element of vital signs measurements in every patient visit, lipid testing, particularly in younger patients, often is not. Moreover, even testing for the at-risk population (smokers, obese patients, those with elevated blood pressure) are often subject to send out testing rather than testing at the point of care. As a result, key opportunities for patient counseling and immediate intervention are often missed. As consultants, a portion of our job is to reinforce the many reasons to test at the point of care and create an environment where patient counseling and immediate prescription of lipid lowering medications can result in optimal patient results.
The facts on management of lipids
Statins were the first lipid management medications proven to lower total cholesterol levels. They were first introduced in 1987 and their use has been rising dramatically since then. Thirty-one million patients were on statins in 2008. Only 10 years later, in 2018, the number had risen to 92 million. It continues to increase annually. In 2002, the FDA approved the use of a different lipid lowering agent, ezetimibe, with a different mechanism of action. Statin lowers lipids by reducing production of lipids in the liver. Ezetimibe lowers lipids by inhibiting cholesterol absorption in the intestine. Physicians often use a “mix and match” approach to using both medications in combination.
What about lipid testing?
The US Preventive Services Task Force (USPTF) is well regarded by physicians for practical, data supported recommendations across multiple patient conditions and tests. Their most recent lipid screening recommendations were first published in 2008. These screening recommendations are to screen asymptomatic men starting at age 35, and those with risk factors beginning at age 20. They recommend initiating screening for women at age 45 if they have no known risk factors and at age 20 if they do. Their recommendations are available at uspreventiveservicestaskforce.org.
Many primary care practices use this information and modify it based on known or suspected patient risk factors including family history, weight and body mass index, blood pressure and other factors. It is worth your time to ask your key customers how they use these recommendations and use that information as a bridge to deeper conversations about the value of testing at the point of care.
POC testing options
Because the linkage between lipid disorders and heart disease has been so well established for so long, a broad range of lipid testing solutions is available. There are multiple fast, accurate waived lipid testing solutions and your key lab suppliers will each offer their reasoning for why their option has distinct advantages. In addition, for larger labs with well-established, full-service laboratories, there are a multitude of automated chemistry testing solutions in the market. Their primary advantage is cost, but since lipid tests are often batched on systems of this type, results may not be available at the point of care. These are trade-offs you need to be familiar with and prepared to discuss with your customers and prospects. From a result quality perspective, NIH National Cholesterol Education Program established performance metrics over three decades ago and methods on the market today meet or exceed these standards. Ask your key lab supplier for more information to be prepared for customer questions about result quality. Many customers still equate waived tests as “adequate” but not as good as moderate complexity tests for the same analyte. For lipid testing, there is no evidence this is true.
CPT codes
The Clinical Lab Fee Schedule (CLFS) of Medicare defines a lipid panel as cholesterol (total, HDL and LDL) and triglycerides with the CPT code 80061 with and without the QW (waived test) modifier. The reimbursement is national and the latest 2004 CLFS reimbursement was $13.00. Stand-alone direct LDL testing is covered by CPT code 83721 (with and without QW modifier) and reimburses $11.00. As a rule, Medicare payers discourage “unbundling” test panels. Be sure to stay informed by learning the rules in your area with home office and key manufacturer guidance. When in doubt, assume “unbundling” is a bad idea and should be discouraged.
Every year, millions of Americans with lipid disorders, diagnosed or otherwise, visit their primary care practice. Based on the prevention and treatment guidelines presented above, many of these patients would benefit from immediate lipid screening along with routine vital signs monitoring. Your customers should be providing these key services. If they are not, you owe it to yourself and these key customers to engage in discussions along with your key lab manufacturers to point out the clear and undeniable evidence that routine measurement of lipid tests at the point of care leads to better health outcomes.
Commit to this strategy with your key lab manufacturers and you will be making a difference for patient satisfaction and the overall health of your community. Your customers will thank you.