Effects of fish oil-derived fatty acids on suboptimal cardiovascular health: A multicenter, randomized, double-blind, placebo-controlled trial

Highlights

• Suboptimal health was reported to be common and associated with chronic diseases.

• Suboptimal cardiovascular health was firstly to be defined in the present study.

• The intake of n-3 LCPUFA improved suboptimal cardiovascular health.

• N-3 LCPUFA intakes did not decrease cardiovascular risk.

Abstract

Background and aims

Suboptimal health and metabolic disorders are common in the general population. Both are related to cardiovascular disease. Suboptimal cardiovascular health is defined by the presence of both suboptimal health and metabolic disorders. The aim of the study was to investigate the potential benefit of n-3 long-chain polyunsaturated fatty acids (LCPUFA) in participants with suboptimal cardiovascular health.

Methods and results

A total of 422 participants with suboptimal cardiovascular health, from two clinics in China, were enrolled from September 2014 to April 2015. All the enrolled participants were randomly assigned to receive 4 g/d of fish oil or placebo for three months. Suboptimal health was defined using an accepted questionnaire. Metabolic disorders were defined as one or more abnormalities in blood pressure, fasting plasma glucose, blood lipids, and body mass index (BMI). After treatment, the mean BMI fell significantly more in the n-3 LCPUFA group than in the placebo group (−0.29 ± 0.06 kg/m² vs. −0.02 ± 0.06 kg/m², P = 0.003). Similar results were found in the changes of suboptimal health status and suboptimal cardiovascular health status (P < 0.05 for all). In a multivariate analysis, the n-3 LCPUFA group was 5.44 (1.15, 25.67) times more likely to have optimal cardiovascular health status after treatment.

Conclusions

n-3 LCPUFA intake improved suboptimal cardiovascular health in this placebo-controlled, randomized, double-blind trial.

Trial registration

This study is registered at www.clinicaltrials.gov NCT02103517.

Introduction

A recent study reported the presence of a preclinical state between health and disease, defined as a suboptimal health status [1]. Suboptimal health status is characterized by self-reported general weakness, low energy, and ambiguous health complaints but absence of a diagnosable condition, which has been reported to be common in the general population [2], [3]. People with this health status may be more vulnerable to chronic diseases because of the association between suboptimal health, cardiovascular risk, and chronic psychosocial stress [4], [5]. Nevertheless, suboptimal health is reversible [6]. The early management of suboptimal health may prevent the development of clinical diseases and promote the maintenance of health.

Metabolic disorders are closely related to cardiovascular disease (CVD) [7]. Similar to suboptimal health, metabolic disorders are modifiable and were actually defined as characterizing suboptimal health in the literature [8]. Considering the relationships between both suboptimal health and metabolic disorders with cardiovascular risk, we defined a status of suboptimal cardiovascular health characterized by the presence of both suboptimal health and metabolic disorders. With regard to the evaluation of cardiovascular risk, suboptimal cardiovascular health status may be superior to metabolic disorders or suboptimal health status alone because it reflects not only metabolic index levels but also self-reported health status. Thus, the prevention of suboptimal cardiovascular health status may significantly reduce CVD risk.

Numerous prospective cohort studies and randomized, controlled clinical trials have shown a beneficial association between n-3 long-chain polyunsaturated fatty acids (LCPUFA) and CVD [9], [10]. The American Heart Association (AHA) recommended the administration of n-3 fatty acids for cardiovascular risk modification due to the ability of these compounds to lower triglyceride concentrations, prevent serious arrhythmias, and lower blood pressure [11], [12], [13]. We hypothesize that the intake of n-3 LCPUFA may be beneficial with respect to suboptimal cardiovascular health.

In a multicenter, randomized, double-blind, and placebo-controlled trial of participants with suboptimal cardiovascular health, we investigated whether n-3 LCPUFA consumption improved suboptimal cardiovascular health and reduced cardiovascular risk.