The effect of omega-3 polyunsaturated fatty acids on stroke treatment and prevention: a systematic review and meta-analysis

Background: in recent years, n-3 PUFAs have been confirmed to be associated with cardiovascular and cerebrovascular diseases, but the link between n-3 PUFAs and stroke remains controversial. Objective: this study aimed to evaluate the association between n-3 PUFAs and stroke. Methods: we performed a comprehensive search of the following electronic databases: PubMed, Embase, Cochrane Library, Web of Science and CNKI. Literature screening and quality assessment were performed according to inclusion and exclusion criteria. Cochrane's tool was used to assess the methodological components of each study, and the Stata 15.1 software was used to perform the meta-analysis. Results: a total of 18 RCTs were included, and the meta-analysis showed no differences in vascular disease-related death between the n-3 PUFA and control groups (RR, 0.95, 95 % CI: 0.89 to 1.01, p = 0.114 > 0.05). However, there was a significant difference in the lower n-3 PUFA dose subgroup (RR, 0.93, 95 % CI: 0.87 to 0.99, p = 0.034 < 0.05). Oral administration of n-3 PUFAs did not significantly reduce the risk of the following cerebrovascular accidents: stroke (RR = 1.00, 95 % CI: 0.93 to 1.07, p = 0.983 > 0.05), ischemic stroke (RR = 0.99, 95 % CI: 0.896 to 1.094, p = 0.841 > 0.05), hemorrhagic stroke (RR = 1.249, 95 % CI: 0.939 to 1.662, p = 0.127 > 0.05) and TIA (RR = 1.016, 95 % CI: 0.882 to 1.170, p = 0.824 > 0.05). The levels of TC (SMD, -0.167, 95 % CI: -0.193 to -0.141, p = 0 < 0.05) and TG (SMD, -0.065, 95 % CI: -0.087 to -0.042, p = 0 < 0.05) in the n-3 PUFA group were significantly decreased, but no significant improvement in the LDL (SMD, 0.022, 95 % CI: 0.005 to 0.040, p = 0.889 > 0.05) and HDL (SMD, 0.008, 95 % CI: -0.009 to 0.025, p = 0.368 > 0.05) levels was observed. Conclusion: this systematic review and meta-analysis suggests that treatment with low-dose n-3 PUFAs can reduce cerebrovascular disease-related death. After the oral administration of n-3 PUFAs, the levels of TC and TG decreased significantly, but n-3 PUFAs did not prevent the occurrence of cerebrovascular accidents or improve LDL or HDL levels.