Health News and Research

Omega-3 fish oil supplements beat statin drugs for lowering mortality risk

The April 2005 issue of the prestigious Archives of Internal Medicine published a review of the effects of various lipid lowering regimens on overall mortality and mortality from coronary heart disease.

Researchers from Basel Institute for Clinical Epidemiology and University Hospital in Basel, Switzerland reviewed over 10,000 clinical trials published between 1965 and 2003 and chose 97 for statistical evaluation in this meta-analysis.  These 97 trials were chosen because of their randomized, controlled and scientifically valid data. They included 275,000 subjects. The current analysis compared the association with mortality risk of diet, lipid lowering drugs categorized as statins, fibrates and resins, and the nutritional supplements omega-3 fatty acids (commonly found in fish oils) and niacin.

While the fibrate class of drugs failed to influence overall mortality and mildly elevated noncardiac mortality, and while diet, resins and niacin appeared to provide insignificant benefits, statins and omega-3 fatty acids significantly lowered both overall and coronary heart disease mortality risk during the trial periods.

The risk of overall mortality was reduced by 13 percent by statins.  You will find this statistic publicized by the pharmaceutical companies that manufacture statins.  Mortality risk was reduced 23 percent by omega-3 fatty acid supplements - Omega-3 fatty acids provided almost double the benefit of statins. When the risk of mortality from heart disease alone was analyzed, the use of statin drugs and omega-3 fatty acids were found to lower the risk by 22 and 32 percent, respectively.

Note to Physicians: If your pharma rep failed to relay this detail to you and you think it is important, what else have they neglected to tell you?

The superiority of omega-3 supplements in lowering the risk of overall and cardiac mortality cannot be explained by an ability to reduce cholesterol.  Cholesterol reduction from Omega-3 averaged 2 percent in this meta-analysis compared to an average reduction of 20 percent achieved via the use of statins. The protection provided by omega-3 fatty acids against heart arrhythmias, along with their antithrombotic and anti-inflammatory properties may be responsible for the mortality risk reduction suggested by this review.

Abstract

Effect of Different Antilipidemic Agents and Diets on Mortality: A Systematic Review

Marco Studer, MD; Matthias Briel, MD; Bernd Leimenstoll, MD; Tracy R. Glass, MSc; Heiner C. Bucher, MD, MPH

Background Guidelines for the prevention and treatment of hyperlipidemia are often based on trials using combined clinical end points. Mortality data are the most reliable data to assess efficacy of interventions. We aimed to assess efficacy and safety of different lipid-lowering interventions based on mortality data.

Methods We conducted a systematic search of randomized controlled trials published up to June 2003, comparing any lipid-lowering intervention with placebo or usual diet with respect to mortality. Outcome measures were mortality from all, cardiac, and noncardiovascular causes.

Results A total of 97 studies met eligibility criteria, with 137,140 individuals in intervention and 138,976 individuals in control groups. Compared with control groups, risk ratios for overall mortality were 0.87 for statins (95% confidence interval [CI], 0.81-0.94), 1.00 for fibrates (95% CI, 0.91-1.11), 0.84 for resins (95% CI, 0.66-1.08), 0.96 for niacin (95% CI, 0.86-1.08), 0.77 for n-3 fatty acids (95% CI, 0.63-0.94), and 0.97 for diet (95% CI, 0.91-1.04).

Compared with control groups, risk ratios for cardiac mortality indicated benefit from statins (0.78; 95% CI, 0.72-0.84), resins (0.70; 95% CI, 0.50-0.99) and n-3 fatty acids (0.68; 95% CI, 0.52-0.90). Risk ratios for noncardiovascular mortality of any intervention indicated no association when compared with control groups, with the exception of fibrates (risk ratio, 1.13; 95% CI, 1.01-1.27).

Conclusions Statins and n-3 fatty acids are the most favorable lipid-lowering interventions with reduced risks of overall and cardiac mortality. Any potential reduction in cardiac mortality from fibrates is offset by an increased risk of death from noncardiovascular causes.

Author Affiliations: Basel Institute for Clinical Epidemiology (Drs Studer, Briel, and Bucher and Ms Glass) and Department of Internal Medicine (Drs Studer and Leimenstoll), University Hospital Basel, Basel, Switzerland.

Source

Arch Intern Med. 2005 Apr 11;165(7):725-30.
 

Key concepts: Omega-3 fish oil, statin drugs, mortality, heart disease