The Limited Effect of omega-3 Polyunsaturated Fatty Acids on Cardiovascular Risk in Patients With Impaired Glucose Metabolism: A Meta-Analysis

Clin Biochem. 2014 Apr;47(6):369-77. doi: 10.1016/j.clinbiochem.2013.11.025. Epub 2013 Dec 14.

Abstract

Objectives: The impacts of marine-derived n-3 polyunsaturated fatty acids (n-3 PUFAs) on cardiovascular risk are not well known. We conducted this meta-analysis to determine the effects of n-3 PUFAs on cardiovascular outcomes and cardiovascular risk markers in patients with impaired glucose metabolism (IGM).

Design and methods: We searched PUBMED, EMBASE, The Cochrane Library and reference lists of relevant papers for high quality randomized controlled trials comparing dietary intake of n-3 PUFAs with placebo in IGM patients. Data was extracted and quality assessed independently by two reviewers. Authors were contacted for missing information. Overall estimates were calculated using a random-effects model or a fixed-effects model, and the possibility of publication bias was examined using a funnel plot. Subgroup analyses were conducted to explore the association between the risk markers and study characteristics.

Results: Our meta-analysis included 19 studies, 24,788 patients. Compared with placebo, n-3 PUFAs had no statistically significant reduce effect on cardiovascular mortality, major cardiovascular events, all-cause mortality or composite endpoint of all-cause mortality or hospitalization for cardiovascular cause, however it can significantly reduce the level of triglycerides (weighted mean difference [WMD] -0.25mmol/L; 95% CI -0.37 to -0.13: p<0.001; 12 trials, 13,921 patients).

Conclusion: Marine-derived n-3 polyunsaturated fatty acids have no protective effect on cardiovascular mortality, major cardiovascular events, all-cause mortality and composite endpoint of all-cause mortality or hospitalization for cardiovascular cause in IGM patients, but can reduce triglyceride level.

Keywords: Cardiovascular risk markers; Docosahexaenoic acid; Eicosapentaenoic acid; Impaired glucose metabolism; Omega-3 polyunsaturated fatty acids.

Publication types

  • Meta-Analysis
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers / metabolism
  • Blood Glucose / metabolism
  • Blood Pressure
  • Cardiovascular Diseases / blood
  • Cardiovascular Diseases / metabolism*
  • Cardiovascular Diseases / physiopathology
  • Fasting / blood
  • Fatty Acids, Omega-3 / pharmacology*
  • Genetic Heterogeneity
  • Glucose / metabolism*
  • Glycated Hemoglobin A / metabolism
  • Heart Rate
  • Humans
  • Lipids / blood
  • Publication Bias
  • Risk Factors
  • Treatment Outcome
  • Vasodilation / drug effects

Substances

  • Biomarkers
  • Blood Glucose
  • Fatty Acids, Omega-3
  • Glycated Hemoglobin A
  • Lipids
  • Glucose