An Expert Panel Takes a Closer Look at Non-Fasting Lipid Profiles and Cardiovascular Risk Assessment
In the fight against cardiovascular diseases (CVD), clinicians and research scientists are on a perpetual quest to understand and mitigate the myriad of factors that contribute to the risk of heart disease. While the lowering of Low-Density Lipoprotein Cholesterol (LDL-C) has been a longstanding target, considerable attention is being redirected toward the levels of Triglyceride (TG)-rich lipoproteins during both fasting and non-fasting states. As science moves toward more practical, patient-friendly methods of monitoring lipid levels, a recent statement by an expert panel sheds light on the relevance of postprandial hypertriglyceridemia in present-day clinical practice. The insights that follow, drawn from their seminal work, may pave the way for more effective prediction and prevention of atherosclerotic Cardiovascular Disease (ASCVD).
The Backdrop: Understanding the Residual Risk
Despite aggressive interventions aimed at lowering LDL-C, a significant residual risk for CVD remains. This risk represents the gap between theoretically ideal cardiovascular health and the risk that persists after LDL-C levels have been treated to target levels. Experts posit that one contributing factor to this residual risk could be elevated levels of TG-rich lipoproteins not just in the fasting state but also in the postprandial (after eating) state.
The Need for a Standardized Test
In their effort to update the guidelines previously set in 2011, the expert panel considered new studies that have emerged, applicable to a diverse array of patient categories. They emphasize the need for a standardized Oral Fat Tolerance Test (OFTT), which could potentially enhance predictions of ASCVD risk alongside existing lipid profiles. To this end, they have generated a consensus based on current research and clinical opinion to guide the medical community in the identification of patients who may benefit from postprandial triglyceride testing.
Key Findings and Recommendations of the Panel
According to the statement, individuals with fasting TG levels below 1 mmol/L (89 mg/dL) generally do not exhibit an abnormal response to an OFTT. Conversely, individuals who have fasting TG levels equal to or greater than 2 mmol/L (175 mg/dL), or non-fasting levels above 2.3 mmol/L (200 mg/dL), typically demonstrate an adverse response to the test.
For those with intermediate fasting TG levels—between 1-2 mmol/L (89-175 mg/dL)—or non-fasting levels of 1.3-2.3 mmol/L (115-200 mg/dL), the panel suggests considering postprandial hypertriglyceridemia testing as an adjunct to other metabolic risk factors, such as obesity, tobacco use, metabolic syndrome, hypertension, and diabetes mellitus. The proposed abnormal threshold for an OFTT (which comprises 75 g of fat, 25 g of carbohydrates, and 10 g of proteins) is a TG response surpassing 2.5 mmol/L (220 mg/dL). These guidelines offer a nuanced approach to patient assessment, considering the complexity of lipid metabolism and its role in cardiovascular health.
The Emerging Role of Postprandial Hypertriglyceridemia
Postprandial hypertriglyceridemia has come under the spotlight as a potential contributing factor to residual cardiovascular risk. The panel’s statement underscores the need for further research in this area to conclusively determine the link between postprandial TG levels and CVD. Prospective studies employing a standardized OFTT can offer a consistent framework for investigation, aiding in the accumulation of comparable and reliable data across different studies.
Practical Implications for Clinical Practice
The expert panel acknowledges that the implementation of OFTT will primarily serve research endeavors aimed at clarifying the role of TG in terms of CV risk. Yet, for routine clinical practice, a shift towards the use of single non-fasting samples is increasingly supported. This practical approach aligns with the patient-centric trend in medicine that emphasizes minimal patient burden without compromising the accuracy and efficacy of cardiovascular risk stratification.
Continued Vigilance and Open Questions
The statement is a call for continuous vigilance in the domain of cardiovascular risk assessment. As therapeutic strategies evolve, so must the instruments we use to predict patient outcomes. While the use of non-fasting lipid profiles become more prevalent, medical professionals must remain curious and critical, asking pivotal questions about the most effective ways to incorporate these new standards into their practices for the benefit of their patients.
Conclusion
The 2019 Expert Panel Statement represents a significant leap forward in our understanding of the complex interplay between lipid metabolism and cardiovascular health. By shining a spotlight on postprandial hypertriglyceridemia, the panel not only proposes practical guidelines for today’s clinicians but also opens the door to a realm of new research possibilities. A marriage between traditional risk factors and emerging markers such as OFTT responses may hold the key to unlocking a deeper understanding of residual CV risk, fostering the development of novel and targeted interventions to combat cardiovascular diseases.
Referenes
1. Kolovou, G. D., Watts, G. F., Mikhailidis, D. P., Pérez-Martínez, P., Mora, S., Bilianou, H., … & Nordestgaard, B. G. (2019). Postprandial Hypertriglyceridaemia Revisited in the Era of Non-Fasting Lipid Profile Testing: A 2019 Expert Panel Statement, Main Text. Current Vascular Pharmacology, 17(5), 498-514. doi: 10.2174/1570161117666190507110519
2. Bansal, S., Buring, J. E., Rifai, N., Mora, S., Sacks, F. M., & Ridker, P. M. (2007). Fasting compared with nonfasting triglycerides and risk of cardiovascular events in women. JAMA, 298(3), 309-316. doi:10.1001/jama.298.3.309
3. Langsted, A., Freiberg, J. J., & Nordestgaard, B. G. (2008). Fasting and nonfasting lipid levels: influence of normal food intake on lipids, lipoproteins, apolipoproteins, and cardiovascular risk prediction. Circulation, 118(20), 2047-2056. doi:10.1161/CIRCULATIONAHA.108.804146
4. Mora, S., Rifai, N., Buring, J. E., & Ridker, P. M. (2008). Fasting compared with nonfasting lipids and apolipoproteins for predicting incident cardiovascular events. Circulation, 118(10), 993-1001. doi:10.1161/CIRCULATIO
5. Nordestgaard, B. G., & Varbo, A. (2014). Triglycerides and cardiovascular disease. Lancet, 384(9943), 626-635. doi:10.1016/S0140-NAHA.108.7773346736(14)61177-6
Keywords
1. Non-fasting lipid profiles
2. Postprandial hypertriglyceridemia
3. Cardiovascular risk assessment
4. Oral Fat Tolerance Test (OFTT)
5. Residual cardiovascular risk