Context The Second Report of the National Cholesterol Education Program (NCEP)
Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol
in Adults (Adult Treatment Panel II) was issued without the benefit of multiple
recently published large clinical trials.
Objective To analyze the panel's guidelines for treatment of high cholesterol
levels in the context of currently available clinical trial results.
Data Sources MEDLINE was searched for all English-language clinical trial data from
1993 through February 1999 relating to the effects of cholesterol treatment
on cardiovascular clinical outcomes.
Study Selection Studies that were selected for detailed review assessed the effects
of cholesterol lowering on either coronary events, coronary mortality, stroke,
and/or total mortality, preferably by randomized, double-blind, placebo-controlled
design. Selection was by consensus of a general internist, a lipid clinic
director, and a researcher in atherosclerotic plaque biology. A core of 37
of the 317 initially screened studies were selected and used as the primary
means by which to assess the guidelines.
Data Extraction By consensus of the group, only prespecified end points of trials were
included, unless post hoc analysis addressed issues not studied elsewhere.
Data Synthesis Recent clinical trial data mostly support the Adult Treatment Panel
II guidelines for cholesterol management. While existing trials have validated
the target low-density lipoprotein cholesterol (LDL-C) goals in the report,
studies are lacking that address mortality benefit from reduction below these
levels. Few lipid-lowering trials have treated patients with low high-density
lipoprotein cholesterol and/or elevated triglyceride levels with LDL-C levels
at or below treatment goals.
Conclusions Lipid-lowering therapy generally should be more aggressively applied
to patients with diabetes and/or at the time of coronary heart disease (CHD)
diagnosis. The evidence for statin use in secondary CHD prevention in postmenopausal
women outweighs current evidence for use of estrogen replacement in this setting.
Further studies are needed to address the effects of lipid modification in
primary prevention of CHD in populations other than middle-aged men and to
study markers of lipid metabolism other than LDL-C.