by Antonella Macerollo
For September 2021, we have selected: Ramsden CE et al. Dietary alteration of n-3 and n-6 fatty acids for headache reduction in adults with migraine: randomized controlled trial. BMJ 2021; 374:n1448 | doi: 10.1136/bmj.n1448
Our research paper of the month is a three arm, parallel group, randomized, modified double blind, controlled trial investigating whether increase n-3 fatty acids in the diet with and without reduction in n-6 linoleic acid can alter circulating lipid mediators implicated in headache pathogenesis and decrease headache in adults with migraine.
Ramsden et al recruited 182 participants (88% women, mean age 38 years) with migraines on 5-20 days per month (67% with chronic migraine) in an academic medical center in the United States over 16 weeks.
Three diets designed with eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and linoleic acid altered as controlled variables: H3 diet (n=61; increase EPA+DHA to 1.5 g/day and maintain linoleic acid at around 7% of energy); H3-L6 diet (n=61; increase n-3 EPA+DHA to 1.5 g/day and decrease linoleic acid to ≤1.8% of energy); control diet (n=60; maintain EPA+DHA at <150 mg/day and linoleic acid at around 7% of energy).
The primary endpoints were the antinociceptive mediator 17-hydroxydocosahexaenoic acid (17-HDHA) levels in blood and the headache impact test (HIT-6).
Our authors of the month found that the H3-L6 and H3 diets increased circulating 17-HDHA (log ng/mL) compared with the control diet (baseline adjusted mean difference 0.6, 95% confidence interval 0.2 to 0.9; 0.7, 0.4 to 1.1, respectively). The
observed improvement in HIT-6 scores in the H3-L6 and H3 groups was not statistically significant (−1.6, −4.2 to 1.0, and −1.5, −4.2 to 1.2, respectively).
Compared with the control diet, the H3-L6 and H3 diets decreased total headache hours per day (−1.7,−2.5 to −0.9, and −1.3, −2.1 to −0.5, respectively), moderate to severe headache hours per day (−0.8, −1.2 to −0.4, and −0.7, −1.1 to −0.3, respectively), and headache days per month (−4.0, −5.2 to −2.7, and −2.0, −3.3 to −0.7, respectively). The H3-L6 diet decreased headache days per month more than the H3 diet (−2.0, −3.2 to −0.8), suggesting additional benefit from lowering dietary linoleic acid. The H3-L6 and H3 diets altered n-3 and n-6 fatty acids and several of their nociceptive oxylipin derivatives in plasma, serum, erythrocytes or immune cells, but did not alter classic headache mediators calcitonin gene related peptide and prostaglandin E2.
Overall, the H3-L6 and H3 interventions altered bioactive mediators implicated in headache pathogenesis and decreased frequency and severity of headaches, but they did not significantly improve quality of life. Although our paper of the month opens a new scenario in treating headaches with dietary changes, further interventions need to be developed to improve the quality of life of this group of patients.