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Effect of omega-3 fatty acid supplementation on cancer incidence, non-vascular death, and total mortality: a meta-analysis of randomized controlled trials.

ABSTRACT:

Background

Omega-3 fatty acids are known to prevent cardiac death. However, previous observational studies have suggested that omega-3 fatty acids are associated with cancer risk in adults. We conducted a meta-analysis based on randomized controlled trials to evaluate the effect of omega-3 fatty acids on the risk of cancer incidence, nonvascular death, and total mortality.

Methods

In February 2013, we performed electronic searches in PubMed, EmBase, and the Cochrane Library to identify randomized controlled trials on cancer incidence, nonvascular death, and total mortality. Relative risk (RR) was used to measure the effect of omega-3 fatty acid supplementation on the risk of cancer incidence, nonvascular death, and total mortality using a random-effect model. The analysis was further stratified by factors that could affect the treatment effects.

Results

Of the 8,746 identified articles, we included 19 trials reporting data on 68,954 individuals. These studies reported 1,039 events of cancer, 2,439 events of nonvascular death, and 7,025 events of total mortality. Omega-3 fatty acid supplementation had no effect on cancer incidence (RR, 1.10; 95% CI: 0.97-1.24; P?=?0.12), nonvascular death (RR, 1.00; 95% CI: 0.93-1.08; P?=?1.00), or total mortality (RR, 0.95; 95% CI: 0.88-1.03; P?=?0.24) when compared to a placebo. Subgroup analysis indicated that omega-3 fatty acid supplementation was associated with a reduction in total mortality risk if the proportion of men in the study population was more than 80%, or participants received alpha-linolenic acid.

Conclusions

Omega-3 fatty acid supplementation does not have an effect on cancer incidence, nonvascular death, or total mortality.

SUBMITTER: Zhang YF

PROVIDER: S-EPMC3938028 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature

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Publications

Effect of omega-3 fatty acid supplementation on cancer incidence, non-vascular death, and total mortality: a meta-analysis of randomized controlled trials.

Zhang Yu-Fei YF Gao Hong-Fang HF Hou An-Ji AJ Zhou Yu-Hao YH

BMC public health 20140226

<h4>Background</h4>Omega-3 fatty acids are known to prevent cardiac death. However, previous observational studies have suggested that omega-3 fatty acids are associated with cancer risk in adults. We conducted a meta-analysis based on randomized controlled trials to evaluate the effect of omega-3 fatty acids on the risk of cancer incidence, nonvascular death, and total mortality.<h4>Methods</h4>In February 2013, we performed electronic searches in PubMed, EmBase, and the Cochrane Library to ide ...[more]

PMID: 24568238

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Project description:BackgroundThe clinical benefits of omega-3 fatty acids (FAs) supplementation in preventing and treating coronary heart disease (CHD) remain controversial. Therefore, this study aimed to investigate the clinical benefits of omega-3 FA supplementation, with special attention given to specific subgroups.MethodsRandomized controlled trials (RCTs) that compared the effects of omega-3 FA supplementation for CHD vs. a control group and including at least 1,000 patients were eligible for the inclusion in this meta-analysis. The relative risk (RR) of all-cause death, major adverse cardiovascular events (MACEs), cardiovascular death, myocardial infarction (MI), stroke, and revascularization were estimated. We analyzed the association between cardiovascular risk and omega-3 FA supplementation in the total subjects. We focused on the cardiovascular risk compared to omega-3 FA in subgroups with different development stages of CHD, omega-3 FA supplementation application dose, diabetes, and sex. PROSPERO Registration Number: CRD42021282459.ResultsThis meta-analysis included 14 clinical RCTs, including 1,35,291 subjects. Omega-3 FA supplementation reduced the risk of MACE (RR; 0.95; CI: 0.91-0.99; p for heterogeneity 0.27; I 2 = 20%; p = 0.03), cardiovascular death (RR; 0.94; CI: 0.89-0.99; p for heterogeneity 0.21; I 2 = 25%; p = 0.02), and MI (RR; 0.86; CI: 0.79-0.93; p for heterogeneity 0.28; I 2 = 19%; p < 0.01), but had no significant effect on all-cause death, stroke, and revascularization. In the subgroup analysis, omega-3 FA supplementation decreased the incidence of MACE and cardiovascular death in acute patients with MI, the risk of MI and stroke in patients with CHD, and the risk of MI in patients with high-risk CHD. 0.8-1.2 g omega-3 FA supplementation reduced the risk of MACE, cardiovascular death, and MI. It was revealed that gender and diabetes have no significant association between omega-3 FA supplementation and MACE risk.ConclusionsOmega-3 FA supplementation had a positive effect in reducing the incidence of MACE, cardiovascular death, MI. Regardless of the stage of CHD, omega-3 FA supplementation can prevent the occurrence of MI. The 0.8-1.2 g omega-3 FA supplementation alleviated CHD risk more effectively than lower or higher doses.Systematic review registrationhttps://www.crd.york.ac.uk/prospero/, identifier CRD42021282459.

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Dataset Information

Effect of omega-3 fatty acid supplementation on cancer incidence, non-vascular death, and total mortality: a meta-analysis of randomized controlled trials.

Background

Methods

Results

Conclusions

Publications

Effect of omega-3 fatty acid supplementation on cancer incidence, non-vascular death, and total mortality: a meta-analysis of randomized controlled trials.

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