Excerpt

In December 2006 the Food and Drug Administration (FDA) held a public hearing on lipoprotein subfractions (www.fda.gov/OHRMS/DOCKETS/ac/06/transcripts/2006-4263t1-01t.pdf, accessed Feb 19, 2008). Several questions were formulated from this meeting regarding the use of low density lipoprotein (LDL) (and high density lipoprotein (HDL)) subfractions for clinical decision making. Based on this hearing, the Centers for Medicare & Medicaid Services (CMS) requested a review of the literature on LDL subfractions and the risk of cardiovascular heart disease (CVD). After an early overview of the potentially relevant literature by the Tufts Evidence-based Practice Center (Tufts EPC), the questions of interest for this report were restricted to a description of the measurement methods that potentially could be routinely used by clinical laboratories, comparisons of the different measurement methods, a review of the evidence regarding the association between LDL subfractions and CVD, and a review of studies that evaluated an intervention that may “improve” LDL subfraction profiles and also evaluated cardiovascular outcomes. The primary population of interest for this review is the over age 65 Medicare population; however, data from all adults are also of interest to CMS.

Contents

• Abbreviations
• 1. Introduction
  • Key questions to be addressed
• 2. Methods
  • Search Strategy
  • Classification of LDL Subfraction Methods (Tests)
  • Study Selection
  • Data Extraction
  • Quality Assessment
  • Applicability Assessment
  • Summary Tables
• 3. Results
  • Literature Search
  • Question 1
  • Question 2
  • Question 3
  • Question 4
• 4. Discussion
  • LDL subfraction methodology
  • Association between LDL subfractions and CVD
  • Limitations
  • Future research
  • Summary
• References
• Appendix A Search Strategy
• Appendix B Rejected Articles
• Appendix C Potential Treatment Studies

This report is based on research conducted by the Tufts Evidence-based Practice Center (EPC) under contract to the Agency for Healthcare Research and Quality (AHRQ), Rockville, MD (Contract No. 290-02-0022). The findings and conclusions in this document are those of the authors who are responsible for its contents. The findings and conclusions do not necessarily represent the views of AHRQ. Therefore, no statement in this report should be construed as an official position of the Agency for Healthcare Research and Quality or of the U.S. Department of Health and Human Services.

The information in this report is intended to help health care decision-makers; patients and clinicians, health system leaders, and policymakers, make well-informed decisions and thereby improve the quality of health care services. This report is not intended to be a substitute for the application of clinical judgment. Decisions concerning the provision of clinical care should consider this report in the same way as any medical reference and in conjunction with all other pertinent information, ie, in the context of available resources and circumstances presented by individual patients.

This report may be used, in whole or in part, as the basis for development of clinical practice guidelines and other quality enhancement tools, or as a basis for reimbursement and coverage policies. AHRQ or U.S. Department of Health and Human Services endorsement of such derivative products may not be stated or implied.

None of the investigators has any affiliations or financial involvement related to the material presented in this report.