High Triglyceride Concentrations Prevalent and Undertreated
Reported March 23, 2009
ATLANTA, March 23 — One out of three U.S. adults has an elevated triglyceride level, but very few receive treatment for the probable cardiovascular risk factor, researchers here found.
In fact, only 1.3% used one of three medications indicated to treat hypertriglyceridemia, Earl Ford, M.D., M.P.H., of the CDC, and colleagues reported in the March 23 Archives of Internal Medicine.
They said the low medication rate likely reflects uncertainty about the need for pharmacological treatment of moderately high triglyceride concentrations.
“Until the benefits of treating hypertriglyceridemia that is not characterized by extreme elevations of triglyceride concentration with medications are incontrovertible, therapeutic lifestyle change remains the preferred treatment,” they said.
Because of mounting evidence that an elevated triglyceride concentration is a risk factor for cardiovascular disease, it is important to find out how common the condition is and how often it is treated, they said.
So they examined data on 5,610 participants ages 20 and older from the National Health and Nutrition Examination Surveys gathered between1999 to 2004. There were roughly equal numbers of men and women.
Triglyceride concentration varied widely, from 26 to 3,780 mg/dL (mean 147.4).
Overall, 33.1% had a level considered elevated at 150 mg/dL or higher. Another 17.9% had a level 200 mg/dL or higher, while 1.7% had a level 500 mg/dL or higher, and 0.4% had a level 1,000 mg/dL or higher.
Triglyceride levels were slightly higher when the use of medications known to lower triglyceride levels — statins, fenofibrate, gemfibrozil, and niacin — was taken into account.
Women were significantly less likely to have elevated triglyceride concentrations than men (P<0.001).
For both sexes, those who exercised less than 150 minutes a week were significantly more likely to have a triglyceride concentration of 200 mg/dL or higher (P=0.03).
The prevalence of high total cholesterol (200 mg/dL or higher) rose with increasing triglyceride concentration: 39.1% for levels less than 150 mg/dL, 58.6% for 150 to 200 mg/dL, and 70.5% for 200 mg/dL or higher.
High LDL and low HDL cholesterol were also more prevalent among participants with elevated triglyceride concentrations.
About one 10 (10.5%) had a combination of high total cholesterol, high triglyceride concentration, and low HDL cholesterol.
The researchers said the usefulness of drugs for high triglyceride levels is unclear for patients with concentrations up to 500 mg/dL.
The 2001 report from the National Cholesterol Education Program said there was no need for medication at levels from 150 to 199 mg/dL and that lifestyle changes should be sufficient.
For patients with concentrations from 200 to 499, lifestyle modification should still be the initial therapy, followed by medication if necessary, the report said.
Benefits of pharmacological therapy are clearer for patients with triglyceride concentrations of 500 mg/dL or higher, who are at risk for pancreatitis, the report said. But lifestyle modification should still be included as part of treatment.
However, Dr. Ford and colleagues acknowledged, “the high percentages of participants with a triglyceride concentration of 200 mg/dL or higher who were overweight or obese, who failed to engage in physical activity for approximately 150 minutes per week, or who smoked attest to the challenge confronting healthcare providers in working with their patients to implement therapeutic lifestyle changes.”
In an invited commentary, Warren Thompson, M.D., and Gerald Gau, M.D., of the Mayo Clinic in Rochester, Minn., said “there is little doubt that triglyceride concentration represents an important risk factor.”
They noted, however, that it’s not clear whether reducing triglyceride levels lowers cardiovascular risk.
No individual trials of fibrates have demonstrated a reduction in cardiac or total mortality, and there is little information on the effects of niacin, they said.
Lifestyle changes remain the cornerstone of treatment for patients with triglyceride concentrations from 150 to 500 mg/dL, they said.
However, they noted, “if pharmacologic therapy is deemed necessary, statins have proven effects on mortality and should be tried first.”
If that doesn’t work, they said, fish oil and niacin can be tried, with fibrates reserved for patients with concentrations of 1,000 mg/dL or higher who have not responded to other treatments.
Primary source: Archives of Internal Medicine
Source reference:Ford E, et al “Hypertriglyceridemia and its pharmacologic treatment among U.S. adults” Arch Intern Med 2009; 169: 572-578.