Objectives: To observe the effect of fish oil supplementation on arterial elasticity and blood pressure (BP) in overweight hypertensive patients.

Subjects and methods: This was a double-blind, randomized and placebo-controlled clinical study, in which 52 overweight hypertensive patients from a community were selected and randomly allocated to two groups (26 in the fish oil group (3 g day-1, fish oil capsules) and 26 in the placebo group (only capsules). All the subjects were follow-up for 8 weeks. The arterial elasticity was determined by CVProfilor DO-2020 and expressed as elasticity indexes (C1-large artery and C2-small artery). During the follow-up, totally nine cases were dropped out (three cases from the fish oil group and six cases from the placebo group).

Results: After 8 weeks follow-up, the large artery elasticity in the fish oil group, compared with its baseline, was significantly improved (C1: 15.51.5 vs 12.83.7 ml mm Hg-1 10), whereas no effects were found in the placebo group (C1: 13.03.4 vs 13.43.8 ml mm Hg-1 10), P=0.027, RM-ANOVA across the two groups. The small artery elasticity (C2), BP and pulse pressure were not found any changes, either in the fish oil group or in the placebo group. At same time, the serum soluble vascular cell adhesion molecule-1(sVCAM-1) and leptin levels, the lipid profile and insulin sensitivity index (ISI) as well, did not show significant differences between two groups.

Conclusions: Fish oil supplementation certainly would improve large arterial elasticity but no effect on BP in overweight hypertensive patients. Further study is needed to confirm the benefits of fish oil supplementation on age-related increases in arterial stiffness.