The study should spur research on whether increasing plant-based omega-3s in the diet reduces death and hospitalization, one expert says.
Increasing dietary intake of plant-based omega-3 fatty acids, found in foods such as walnuts and canola oil, may be key to lowering the risks of hospitalization and death in heart failure patients, a new study suggests. study.
Much research has been devoted to associations between marine-based omega-3s such as eicosapentaenoic acid (EPA), found in fatty fish or prescription supplements such as secondary prevention measure in HF, even for prevention of hospitalization for recurrent HF. However, less is known about the benefits of plant-based omega-3s, primarily alpha-linolenic acid (ALA).
“We knew from our previous research that ALA levels at the time of heart attack were related to prognosis,” study co-author Aleix Sala-Vila, PharmD, PhD (Hospital del Mar Medical Research Institute, Barcelona, Spain), he told TCTMD. “So we decided to give it a go and try to find some kind of association between these ALAs and prognosis in heart failure patients.”
Any of us can improve your diet at any time, and [doing so] will result in healthy aging. Aleix Sala-Vila
While most dietary studies use participant reminders or food diaries, Sala-Vila and colleagues, led by Iolanda Lázaro, PhD (Hospital del Mar Medical Research Institute), used blood samples as an indicator of dietary intake of ALA to group patients into quartiles and then followed them for 2.4 years. What they found was that, compared to patients in the lowest quartile, those in the other three quartiles of ALA levels had a 39% reduction in the composite endpoint of all-cause mortality/first hospitalization by CI.
The researchers believe that this causal effect suggests that a higher intake of plant-based foods, or even better absorption of them, could be a target to improve CV health and could ultimately translate into better HF outcomes.
“The important thing is that there is no evidence that including these types of foods in your general diet is going to be harmful to you,” Sala-Vila said. “Any of us can improve their diet at any time, and [doing so] will result in healthy aging.”
In an accompanying editorial, Abdallah Al-Mohammad, MD (University of Sheffield, UK), says that while the findings are hypothetical, the authors’ “proposition of a potential role for this source of nutrition in ameliorating morbidity and mortality rates for patients with heart failure cannot yet be substantiated.”
Al-Mohammad adds that the study provides a push “to test whether higher ALA intake could potentially raise the serum ALA level enough to move a patient into a quartile associated with a better risk profile,” and whether doing so results in better CI results.
Focus on those with lower levels
For the study, published on October 24, 2022, in the Journal of the American College of Cardiology, Lázaro et al. included 905 outpatients (mean age 67 years; 31.7% women) with HF of various aetiologies. Patients were equally represented in all four serum ALA quartiles.
In addition to the reduction seen in the primary composite endpoint, patients in quartiles 2, 3, and 4 had lower rates of all-cause death (P = 0.002), CV death (P = 0.004), first hospitalization for HF (P = 0.003), and the composite of CV death and HF hospitalization (P = 0.001) compared to those in the lowest quartile. However, when comparing between quartiles 2 to 4, no differences were seen in any of the clinical endpoints.
Lázaro and colleagues also point out that, in addition to being safe, ALA-rich foods are also fairly low in cost, which could mean that the greatest benefits are seen in disadvantaged populations with low serum levels.
According to Al-Mohammad, enrollment of HF patients with low ALA levels will most likely be the next step in this research, to clarify that low levels are a marker of increased risk. Sala-Vila said that she agrees.
“Then, we must define how many patients we want to evaluate, what type of food we will give them and the duration of the dose of the food that we are going to test,” added Sala-Vila. But she pointed out the possibility that the benefits of circulating ALA may differ due to genetics or microbiota, which will also be a key determinant of the final effect of any type of intervention to increase ALA in the diet.