The benefits of omega-3 supplements in people with drug-resistant epilepsy require additional investigation, according to a literature review conducted by researchers in Brazil. The report, “Polyunsaturated fatty acid supplementation for drug-resistant epilepsy,” was published in Cochrane Database of Systemic Reviews.
Approximately 2.3 million adults and around 470,000 children in the U.S. have epilepsy, a lifelong neurological condition characterized by recurrent seizures. Patients with epilepsy whose seizures do not successfully respond to anti-seizure drug therapy are considered to have drug-resistant epilepsy or refractory epilepsy. Estimates indicate that as many as 25 to 30 percent of people with epilepsy are likely to have refractory epilepsy.
Different treatment strategies, including the use of omega-3 fatty acid supplements, are currently being tested to see if they provide benefits for seizure control in people with epilepsy. Omega-3 fatty acids can be also be obtained by eating certain fish such as salmon, trout, mackerel, tuna, herring, and sardines.
To investigate the effectiveness and tolerability of omega-3 polyunsaturated fatty acids (PUFA) to help control seizures in people with refractory epilepsy, Maria Torloni at the Universidade Estadual de Ciências da Saúde de Alagoas in Brazil and her colleagues searched several databases for published randomized and quasi-randomized studies, including both adults and children who took omega-3 supplements as part of treatment.
In their eligibility criteria, the researchers included the types of study design; forms of omega-3 supplement; types of participants; seizure freedom, seizure reduction, improvement in quality of life, potential adverse effects, gastrointestinal effects, drop-out rates, and changes in plasma lipid profile.
From all the studies retrieved from their search, three studies comprising 155 people with epilepsy were considered eligible for the review. One study was a placebo-controlled, single-blind trial of 70 children, and two studies were placebo-controlled, double-blind trials that included 85 adults.
When the researchers analyzed the results from the 12-week trial involving only children, they observed that the proportion of children who were free of seizures in the group who received PUFAs was higher than in the group who received a placebo. Researchers also found that the proportion of children who had a 50 percent reduction in seizures was greater in the PUFAs-treatment group compared to the placebo-treated group.
However, according to the researchers, this trial had a high risk of bias because the investigators knew which children were receiving omega-3 supplements and which ones were taking the placebo pill.
When the team reviewed the two trials conducted in adults, they observed no group differences in the proportion of adults who received PUFAs who had a 50 percent reduction in the number of seizures compared to those who received a placebo. Additionally, there were no differences in the mean frequency of seizures, in quality of life, or treatment side effects. Moreover, no differences in gastrointestinal effects were reported.
“In view of the limited number of studies and small sample sizes, there is not enough evidence to support the use of PUFA supplementation in people with refractory epilepsy. More trials are needed to assess the benefits of PUFA supplementation in the treatment of drug-resistant epilepsy,” the authors concluded.