Increasing prevalence of low HDL cholesterol/elevated triglycerides highlights need for more comprehensive lipid control

Data presented at the American Heart Association Annual Scientific Sessions, New Orleans 2008 underscore an urgent need for monitoring and managing high density lipoprotein (HDL) cholesterol and triglycerides. Evidence from the National Health and Nutrition Examination Survey (NHANES) show that the percentage of adults with the combination of low HDL cholesterol and elevated triglycerides doubled over the last 30 years, possibly linked to rising obesity rates. The study was conducted by the National Lipid Association in the US.

 

Cohen JD, Cziraky MJ, Jacobson TA et al. Changes in the prevalence of abnormal lipid fractions among US adults: results from the National Health and Nutrition Examination Survey II, III and 1999-2006. Circulation 2008;118:S_1081-S_1082 [Abstract 1198].

 

The researchers analysed 30-year data from the NHANES database over the periods 1976-1980 (NHANES II), 1988-1994 (NHANES III) and 1999-2006. Low HDL cholesterol was defined as <40 mg/dL, elevated triglycerides by ³150 mg/dL and high low-density lipoprotein (LDL) cholesterol by ³100 mg/dL. Multivariate analysis was used to investigate the relationship between dyslipidemia and obesity (defined as body mass index ³30 kg/m2), controlling for age, gender, race/ethnicity, NHANES group, previous myocardial infarction, diabetes and smoking status.

 

While the management of LDL cholesterol has improved, as shown by a decrease in the percentage of subjects with high LDL cholesterol values (from 43.5% in NHANES II to 36.3% in 1999-2006), there have been far less emphasis on managing HDL cholesterol and elevated triglycerides. The prevalence of the combination of low HDL cholesterol and elevated triglycerides doubled over the same period (from 2.1% to 4.8%). Elevated triglycerides more than tripled (from 1.8% in 1976 to 8.7% in 2006) within the elderly population (>60 years).

 

This increasing prevalence of mixed dyslipidemia has been linked with rising obesity rates, which more than doubled over this time (from 15% in 1976 to 33.7% in 2006). 

 

According to the study lead author, Jerome D. Cohen, Chairman of the National Lipid Association’s consumer affairs committee and professor emeritus of internal medicine and cardiology, St. Louis University School of Medicine, Missouri ‘Studies have shown that unhealthy levels of HDL cholesterol and triglycerides can lead to heart attack and stroke. This study clearly shows the need for increased focus on controlling other components of the lipid profile.’

 

Thomas Bersot, president of the National Lipid Association commented: ‘As Americans age and rates of obesity continue to grow exponentially, it is becoming more important to monitor and manage HDL and triglycerides, along with LDL, to improve heart health.’

 

Additional data reported at the meeting provided further support for the importance of managing lipid abnormalities other than elevated LDL cholesterol.

 

Wong ND, Ghandehari H, Le H et al. Predominant types of dyslipidemia in U.S. adults with coronary heart disease and diabetes. Circulation 2008;118:S_568. [Abstract 5530].

 

In a study including 2,827 subjects from NHANES 2003-2004, diabetes patients with the combination of low HDL cholesterol and elevated LDL cholesterol had more than 8-fold increased odds of coronary heart disease (8.14, 95% CI 4.24-15.60 without elevated triglycerides and 8.80, 95%CI 4.03-19.20 with the combination of all three abnormalities). Nathan Wong, lead author from the University of California, commented that this evidence should be considered when choosing therapies for dyslipidemia.

 

However, a survey from the same group suggests that management of low HDL cholesterol and/or elevated triglycerides is far from optimal.

 

Ghandehari H, Le H, Ambegaonkar B et al. Prevalence of lipid disorders and treatment patterns in overall and high risk U.S. adults with dyslipidemia in 2003-2004. Circulation 2008;118:S_470. [Abstract 3704]

 

The survey included 1,111 US adults aged ³20 years (45% female) with dyslipidemia (defined as elevated LDL cholesterol >100 mg/dL or on lipid modifying therapy) from the NHANES database of whom 609 were identified as being at high risk (i.e., with CHD, diabetes or other CHD risk equivalents).

 

For both the overall study population and high risk subjects, over 40% had low HDL cholesterol (<40 mg/dL in men and <50 mg/dL in women) and/or elevated triglycerides (³200 mg/dL), with or without elevated LDL cholesterol. However, only 34% (39% among high-risk subjects) were receiving lipid modifying therapy. In the majority of cases (80%) this was a statin; less than 10% were receiving non-statin therapy.

 

The authors concluded: ‘There is a large disconnect between high prevalence of low HDL cholesterol and/or elevated triglyceride disorders, with or without elevated LDL cholesterol, and utilisation of therapies targeting these lipids. This is a particular concern among high-risk patients.’

 


Download Attachment