“Isolated” Low High-Density Lipoprotein Cholesterol

Abstract

OBJECTIVE: To present information on the function, structure, and importance of high-density lipoprotein cholesterol (HDL-C) and to evaluate the current literature regarding the controversy of managing patients with an “isolated” low HDL-C concentration. DATA SOURCE: A MEDLINE search was performed (1966–June 1996) to identify English-language clinical and review articles pertaining to HDL-C. Some articles were identified through the bibliography of selected articles. STUDY SELECTION: All articles were considered for possible inclusion in the review. Pertinent information, as judged by the authors, was selected for discussion. DATA EXTRACTION: Important historical lipid studies, recent review articles, and clinical trials involving therapy for HDL-C were evaluated. DATA SYNTHESIS: The structure, function, and measurement of HDL-C and the state of an isolated low HDL-C are discussed for background. Lifestyle modification measures to increase HDL-C, medications to avoid, estrogen replacement, and lipid-altering agents used to raise an isolated low HDL-C are presented. CONCLUSIONS: An isolated low HDL-C concentration poses a risk for coronary heart disease. The management of this state is controversial. The first step in management is in agreement with experts and includes lifestyle modification (e.g., weight reduction, diet, smoking cessation, aerobic exercise). Estrogen replacement therapy and discontinuance of drugs that secondarily lower HDL-C are additional treatment options. The use of lipid-altering agents has been used in some patients. Nicotinic acid appears to be an effective agent for an isolated low HDL-C. A large clinical trial evaluating the effect of treating an isolated low HDL-C for primary and secondary prevention of coronary events is needed.