Hyperlipidemia in Older Adults
To the Editor,
Given the perplexity of choice, I would like to know if non–high-density lipoprotein (HDL) or APO-B have a role in risk assessment of hyperlipidemia in older adults.
Dr. Frank M. Shanley, FACC
Denville, NJ .
Drs. Arnold and Rich respond:
Thank you for your interest in our article.1 Low apolipoprotein A-1 and high apolipoprotein B levels have been shown to be more effective than low-density lipoprotein (LDL) cholesterol levels in predicting myocardial infarction (MI) in some but not all studies involving older adults.2,3 In the Apolipoprotein-related Mortality Risk (AMORIS) study of 175,553 Swedish subjects followed for more than 5 years, decreasing apolipoprotein A-1 and increasing apolipoprotein B levels were found to be strong independent predictors of fatal MI in men and women age 70 years or older.2 More recently, Motta et al3 found that increased apolipoprotein B, dichotomized at 150 mg/dL, was not associated with prevalent MI or stroke at baseline in 3288 Italian subjects age 65-84 years. During a 3-year follow-up period, there was an increased risk for MI but not stroke among subjects with elevated apolipoprotein B, but the analysis did not adjust for LDL cholesterol.3 The authors concluded that their data do not support the use of apolipoprotein B as a risk marker for MI or stroke in older subjects.
Apart from the lack of compelling evidence regarding the role of apolipoproteins in assessing cardiovascular risk in older patients, treatment targets based on these parameters have not been defined, and there are currently no clinical guidelines for managing patients based on apolipoprotein levels. Thus, although this is an area of considerable interest and ongoing research, we do not currently recommend measuring apolipoproteins as a means to assess cardiovascular risk in older patients. With respect to the utility of non–HDL cholesterol, we do not believe that this parameter provides incremental value beyond its components (ie, LDL cholesterol and triglycerides). We therefore recommend basing treatment decisions on LDL cholesterol and triglyceride levels rather than the non–HDL cholesterol level.
Suzanne V. Arnold, MD, and
Michael W. Rich, MD
Cardiovascular Division Washington University School of Medicine
St. Louis, MO