July 18, 2007 - In a related study of over 25,000 initially healthy women, higher triglyceride levels measured after not fasting is associated with an increased risk for cardiovascular events, but his association was not found for triglyceride levels measured after fasting, according to a study in the July 18 issue of JAMA.
Sandeep Bansal, M.D., of Brigham and Women’s Hospital and the Harvard School of Public Health, Boston, and colleagues conducted a study to determine the association of triglyceride levels (fasting vs. nonfasting) and risk of future cardiovascular events. The study included 26,509 initially healthy U.S. women (20,118 fasting and 6,391 nonfasting) participating in the Women’s Health Study, enrolled between November 1992 and July 1995. Triglyceride levels were measured in blood samples obtained at time of enrollment.
During a median (midpoint) follow-up of 11.4 years, 1,001 participants experienced a new cardiovascular event (including 276 nonfatal heart attacks, 265 ischemic strokes, 628 coronary revascularizations, and 163 cardiovascular deaths).
"In this large-scale, prospective cohort of initially healthy U.S. women, we observed that higher nonfasting triglyceride levels were strongly associated with an increased risk of future cardiovascular events, independent of baseline cardiac risk factors, levels of other lipids, and markers of insulin resistance. In contrast, fasting triglyceride levels showed little independent association with cardiovascular events. Associations were particularly strong among individuals who had their blood drawn 2 to 4 hours after a meal, and this relationship weakened as more time elapsed postprandially," the authors write.
"Our observations may have implications for the design and conduct of clinical trials evaluating triglyceride-lowering medications. To date, almost all clinical trials of pharmaceutical agents targeting triglyceride levels have relied on fasting levels as inclusion criteria. However, if levels measured in the fasting state are not the best marker for the atherogenicity associated with hypertriglyceridemia, then it is possible that these trials might have targeted the wrong patient populations. By contrast, previous studies have demonstrated the benefits of several classes of drugs on postprandial elevations in triglyceride levels. Thus, based on the data presented here, future end point reduction trials of triglyceride-lowering agents might consider participant inclusion on the basis of nonfasting rather than fasting triglyceride levels."
Source: (JAMA. 2007;298(3):309-316. Available pre-embargo to the media at www.jamamedia.org)
For more information: www.pubs.ama-assn.org/