Omega-3 fatty acid tied to slower ALS progression, better survival
Benefits seen in patients with high blood levels of alpha-linolenic acid
High blood levels of an omega-3 fatty acid is associated with a significantly slower disease progression and longer life among people with amyotrophic lateral sclerosis (ALS), a study reported.
The link specifically was seen in people with elevated blood levels of an omega-3 fatty acid called alpha-linolenic acid (ALA) — a plant-derived molecule found in flaxseed, walnuts, chia, and canola and soybean oils.
Study findings suggest that eating more of these products may be beneficial for people with ALS, and its scientists hope to confirm these benefits through a clinical trial.
“We found that among people living with ALS, higher blood levels of ALA … associated with a slower disease progression and a lower risk of death within the study period,” Kjetil Bjornevik, an assistant professor of epidemiology and nutrition at Harvard T.H. Chan School of Public Health and the study’s lead author, said in a university press release.
Alpha-linolenic acid or ALA shows ‘neuroprotective’ potential
“These findings, along with our previous research, suggest that this fatty acid may have neuroprotective effects that could benefit people with ALS,” Bjornevik said. Earlier work by these researchers had suggested “that a diet high in ALA and increased blood levels of this fatty acid” lowered a person’s risk of ALS.
The current study, “Association of Polyunsaturated Fatty Acids and Clinical Progression in Patients With ALS: Post Hoc Analysis of the EMPOWER Trial,” was published in the journal Neurology.
While a diet rich in certain omega-3 polyunsaturated fatty acids (PUFAs), namely alpha-linolenic acid, has been linked to a lower ALS risk, whether it might slow disease progression remained largely unknown.
Researchers at the Harvard school set out to determine if PUFA levels could help to predict survival and risk of decline in ALS patients.
They examined blood samples from patients who participated in the Phase 3 EMPOWER trial (NCT01281189), which assessed dexpramipexole as a potential ALS treatment. While generally found to be well tolerated, study results showed the investigative therapy was no better than a placebo at slowing disease progression and extending survival.
Among its 943 participants, 449 patients had available fatty acid analyses from samples collected at trial entry. Most were men, (65.3%), and patients’ mean age was 57.5. They were followed in the trial for 18 months and assessed for disease progression, measured with the ALS Functional Rating Scale Revised (ALSFRS-R), and their time to death was recorded.
Blood levels of ALA notedd for 449 patients taking part in Phase 3 trial
In the current study, supported by a grant from the ALS Association, these EMPOWER patients were categorized into four groups according to their omega-3 PUFA levels, ranging from highest to lowest. Results showed that those with the highest PUFA levels tended to fare better than those with lower levels.
Among all the examined omega-3 PUFAs, ALA showed the greatest benefits. Of the 126 patients who died, 33% had the lowest ALA levels, compared with 19% with the highest ALA levels.
In other words, people with the highest levels had a 50% lower risk of death during study follow-up than those with the lowest levels. Patients with the highest ALA levels also had better scores in a joint assessment of function and survival, indicating a slower disease progression.
The association remained significant when the analyses took into account confounding factors, such as race and ethnicity, body mass index (a measure of body fat), symptom duration, site of disease onset, riluzole use, ALS family history, lung function, and treatment use in the trial.
“Higher levels of ALA were associated with longer survival and slower functional decline in ALS patients. These results suggest that ALA may have a favorable effect on disease progression in ALS patients,” the scientists wrote.
Additional analyses showed that levels of another omega-3 PUFA, called eicosapentaenoic acid, and an omega-6 PUFA known as linoleic acid also associated with a reduced risk of death. Eicosapentaenoic acid can be found in fatty fish and fish oil and linoleic acid in vegetable oils, nuts, and seeds.
The team is now working to launch a clinical trial to determine if ALA can improve patient outcomes.
“The link our study found between diet and ALS is intriguing,” said Alberto Ascherio, MD, PhD, a professor of epidemiology and nutrition at Harvard and the study’s senior author. “We are now reaching out to clinical investigators to promote a randomized trial to determine whether ALA is beneficial in people with ALS. Obtaining funding will be challenging, because ALA is not a patentable drug, but we hope to get it done.”