Abstract P412: Effect of Fish Oil on Circulating Adiponectin: A Systematic Review and Meta-analysis of Randomized Controlled Trials
Background Seafood long chain polyunsaturated omega-3 fatty acids (n-3 PUFA) improve insulin sensitivity in animal experiments, but findings remain inconsistent in humans. Adiponectin is a robust marker for insulin sensitivity and adipocyte function. Whether n-3 PUFA affect adiponectin in humans is unknown.
Aims To perform a systematic review and meta-analysis of randomized placebo-controlled trials (RCTs) to determine the effect of fish or fish oil consumption on circulating adiponectin in humans.
Methods Following PRISMA guidelines throughout, multiple databases were searched through Jun 2012 to identify RCTs of fish oil supplementation or isocaloric fish meal feeding that evaluated adiponectin as an outcome. Two investigators independently extracted data. Effect estimates were pooled using inverse-variance weighted, random effects meta-analysis. Heterogeneity was assessed by the I2 statistic. Pre-specified sources of heterogeneity were investigated by meta-regression. Publication bias was assessed by funnel plots and Egger’s test.
Results Of 110 studies, 14 RCTs met inclusion criteria. 14 trial arms evaluated fish oil, including 682 subjects treated with fish oil and 641 with placebo. Fish oil increased adiponectin by 0.37 μg/mL (95% CI, 0.07-0.67, P=0.02, Figure). Heterogeneity was evident (I2=72.9%), which was not explained by n-3 PUFA dose or duration, study quality score, study location, or baseline BMI (meta-regression P>0.05 each). The funnel plot was slightly asymmetric; Egger’s test did not achieve significance (P=0.11). Only 2 trial arms evaluated fish feeding, including 136 intervention and 68 control subjects, for which the pooled effect on adiponectin was not significant (-0.01μg/mL, 95% CI, -0.65-0.64, P=0.99) although CIs were broad.
Conclusion In placebo-controlled RCTs, fish oil moderately increases circulating adiponectin, supporting benefits of n-3 PUFA consumption on insulin sensitivity and adipocyte function.
- © 2013 by American Heart Association, Inc.