Reducing Cardiac Risk in Patients with Elevated Triglycerides

Jacoby, Douglas S., MD
Director, Penn Cardiology Preventative Care
Medical Director, Penn Presbyterian Health and Vascular Pavilion
Philadelphia, PA
Also by this Author 

The primary objective in managing patients with high triglycerides is to reduce long-term cardiac risk. Dr. Douglas Jacoby, Director, Penn Cardiology Preventative Care discusses the importance of identifying metabolic syndrome in these patients and the role of advanced testing to assess risk more reliably than with traditional measures.

Assessing Cardiac Risk

“There are two main considerations in relation to triglycerides,” notes Dr. Jacoby. “One involves avoiding the risk of acute pancreatitis, and the other reducing long-term cardiac risk. These are important distinctions. When someone's triglycerides are very high, as defined by greater than 500 mg/dl, they are at risk for pancreatitis. When the triglycerides are high, as defined by 200 to 500 mg/dl, that person is not at risk for acute pancreatitis, and should be assessed in terms of risk for heart attack or stroke.1, 2 It is with these patients that metabolic syndrome matters and it does so for two reasons. First, because many patients with metabolic syndrome have high triglycerides. Second, because there are different types of triglycerides:  some driven by carbohydrates and some driven by fat. People with metabolic syndrome have the carbohydrate driven triglycerides, which is consistent with pre-diabetes. People with elevated triglycerides under 500 mg/dl are often very high risk cases but don't necessarily show up on the risk calculators, and so their risk is underestimated.”

Significance of Metabolic Syndrome

“Thinking about metabolic syndrome for patients with high triglycerides is very important,” continues Dr. Jacoby, “but in such cases you shouldn’t focus on reducing the triglycerides, as that is not their primary problem. Their real problem is their high cardiac risk, and when you're trying to lower cardiac risk, the first line agent is to use a statin to treat LDL.  It may seem counter-intuitive but if you have triglycerides that are high, but under 500 mg/dl, the first step is to prescribe a statin, a medicine that's not going to reduce the level of triglycerides.1 To understand the rationale for this one needs to understand the nature of the metabolic syndrome.”

“Metabolic syndrome refers to a constellation of risk factors,” says Dr. Jacoby. “There are various definitions in use but essentially it refers to a combination of obesity, determined by body mass index or waist circumference, hypertension, low HDL, high triglycerides (over 150 mg/dL) and a glucose level of 100 mg/dL or above.3 The presence of three of these five factors indicates metabolic syndrome.” Dr. Jacoby points out, however, that applying a risk calculator to patients with metabolic syndrome does not accurately predict risk, because it doesn’t recognize the small increases in risk, which in aggregate represent significant risk. “In fact, I would encourage physicians not to use the risk calculator as an exclusive decision making tool for people with metabolic syndrome. If metabolic syndrome criteria are met, physicians should consider aggressive treatment. One option is to treat everyone with metabolic syndrome with a statin.”

Advanced Testing to Predict Risk

Another option for managing patients with metabolic syndrome is first to perform more advanced testing, such as measuring apolipoprotein B (ApoB) or LDL particle (LDL-P) number measurement. “The rationale for performing more advanced testing,” explains Dr. Jacoby,  ”is that there's a much higher incidence of discordance in people with metabolic syndrome. In other words, if you compare advanced tests like Apo B or LDL- P with the calculated LDL value (LDL-C), they predict risk differently and more accurately in people with metabolic syndrome. LDL-P is a better predictive agent than LDL-C in people with metabolic syndrome, and there’s a discordance between the two in around 30% of cases.”4, 5

Managing Triglycerides

While the primary area of focus for a patient with high triglycerides under 500 mg/dl is to address overall cardiac risk, the next objective is to manage triglycerides. Firstly, this involves providing dietary advice, which varies based on the type of triglycerides involved. “If the level is over 1,000 mg/dl, it is often fat-driven, consisting of chylomicrons,” notes Dr. Jacoby. “Under 1,000 mg/dl it's typically carbohydrate-driven, and that's VLDL.  So there are different processes to take into account. So it's really important to think about what type of hypertriglyceride unit you are dealing with, so you can give the right dietary advice.  In this respect, I think it's a good idea to refer patients to some form of sophisticated dietary counseling provided over the phone, such as Quest Diagnostics 4myheart® program.”

“With regard to treatment, if the triglycerides level is very elevated that’s what I treat first, with fish oil, preferably of prescription grade, and fibrates. In somebody whose triglycerides level is not very elevated, such as 350 mg/dl, I will still treat their triglycerides, but I'm going to put them on the statin first. It's just a matter of sequence.”

In summarizing the approach to managing patients with elevated triglycerides, when triglycerides are greater than 500 mg/dl, treat triglycerides first to avoid pancreatitis. When triglycerides are under 500 mgdl, focus on reducing long-term cardiac risk. Identifying those with metabolic syndrome and performing advanced testing to assess risk are important components of this approach.

 

References

 

  1. ATP III At-A-Glance: Quick Desk Reference. National Heart, Lung and Blood Institute. http://www.nhlbi.nih.gov/health-pro/guidelines/current/cholesterol-guidelines/quick-desk- reference-html Accessed on February 16, 2015.
  2. Kota Sunil K, Kota Siva K, Jammula S, et al. Hypertriglyceridemia-induced recurrent acute pancreatitis: A case-based review. Indian J Endocrinol Metab. 2012 Jan-Feb; 16(1): 141–143.
  3. Grundy SM, Brewer HB, Cleeman JI et al. Definition of Metabolic Syndrome. Report of the National Heart, Lung, and Blood Institute/American Heart Association Conference on Scientific Issues Related to Definition. Circulation. 2004;109:433-438 http://circ.ahajournals.org/content/109/3/433.full Accessed on February 16, 2016.
  4. Mora S, Buring JE, Ridker PM. Discordance of LDL Cholesterol with Alternative LDL-Related Measures and Future Coronary Events. Circulation .113.005873 Published online before print December 17, 2013 http://circ.ahajournals.org/content/early/2013/12/17/CIRCULATIONAHA.113.005873 . Accessed on February 16, 2016.
  5. Pencina MJ, D’Agostino RB, Zdrojewski T et al. Apolipoprotein B improves risk assessment of future coronary heart disease in the Framingham Heart Study beyond LDL-C and non-HDL-C. Published online before print January 29, 2015, European Journal of Preventive Cardiology January 29, 2015 2047487315569411 http://cpr.sagepub.com/content/early/2015/01/24/2047487315569411.full Accessed on February 16, 2016.