EC Nutrition

Systematic Review Volume 18 Issue 5 - 2023

Fish Oil Supplementation and Circulating Lipoprotein (a) Levels: A Grade-Assessed Systematic Review and Dose-Response Meta-Analysis of 20 Randomized Controlled Trials

Shahrooz Bentyaghoub1, Niki Bahrampour2, Mohsen Mohammadi-Sartang1, Nastaran Rafiepour3, Sepideh Rajabi Nezhad4, Faranak Taghipour1, Hamed Sadeghi-Dehsahraei5, Cain C. T. Clark6, Mohammad Ahmadi7*, Mohsen Ranjbar8, MohammadAli Izadi9

1Department of Clinical Nutrition, School of Nutrition and Food Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
2Department of Nutrition, Science and Research Branch, Islamic Azad University (SRBIAU), Tehran, Iran
3Islamic Azad University, Rasht Branch, Rash, Iran
4Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
5Department of Basic Sciences, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
6Research Institute for Health and Wellbeing, Coventry University, Coventry, CV1 5FB, U.K
7Department of Clinical Sciences, School of Veterinary Medicine, Islamic Azad University of Shahrekord, Shahrekord, Iran
8School of Nursing and Midwifery, Shiraz University of Medical Sciences, Shiraz, Iran
9Department of Sport Sciences, Faculty of educational sciences and Psychology, Shiraz University, Shiraz, Iran

*Corresponding Author: Mohammad Ahmadi, Department of Clinical Sciences, School of Veterinary Medicine, Islamic Azad University of Shahrekord, Shahrekord, Iran.
Received: March 14, 2023; Published: April 06, 2023

Objectives: Although fish oil plays an important role in the prevention of cardiovascular diseases, the results of clinical trial studies regarding its effect on lipoprotein (a) [Lp(a)] concentrations factor are inconsistent. Therefore, we performed a meta-analysis of available randomized controlled trials (RCTs) to elucidate the efficacy of fish oil on plasma Lp(a) concentrations.

Methods: Net changes in Lp(a) were used to calculate the effect size, which was reported as a weighted mean difference (WMD) and 95% confidence intervals (CIs). The inclusion criteria were adult participants and an intervention duration of ≥ 2 weeks. In the primary search, 340 articles were found, of which 37 were assessed in full text and 20 trials (1356 participants) were included in the meta-analysis.

Results: The meta-analysis indicated a significant reduction in plasma Lp(a) levels (WMD: -1.96 mg/L, 95% CI: -3.63 to -0.30; P = 0.021) following fish oil supplementation. In the sub-group analysis, a significant reduction was observed only at doses < 3 g/day (WMD: -7.35 mg/L, 95% CI: -13.80, -0.89, p = 0.026), and with treatment duration ≥ 12 weeks (WMD: -2.56 mg/L, 95% CI: -4.67, -0.45, p = 0.017). A dose-response analysis revealed that < 3 g/day of fish oil largely decreased Lp(a) levels (P-nonlinearity = 0.006).

Conclusion: The current evidence from RCTs showed that fish oil supplementation may significantly reduce Lp(a) levels at doses lower than 3 g/day when the supplementation lasts over 12 weeks. Further well-constructed randomized clinical trials are needed.

Keywords: Fish Oil; Omega-3 Fatty Acid; Lipoprotein (a)

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Mohammad Ahmadi., et al. "Fish Oil Supplementation and Circulating Lipoprotein (a) Levels: A Grade-Assessed Systematic Review and Dose-Response Meta-Analysis of 20 Randomized Controlled Trials". EC Nutrition 18.5 (2023): 74-91.