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| Omega-3 Fatty Acids and Migraine |
Migraine is a common type of severe headache affecting women three times as often as men. The pharmaceuticals most commonly used are addressing pathological events in the blood vessels. Omega-3 fatty acids have well known vascular effects. Three clinical studies are presented demonstrating the effects of omega-3 fatty acids in migraine.
Migraine is a common type of intermittent, severe headache with a prevalence of about 20% in the population, women affected three times as often as men. The first attack is usually occurring in early adolescence. There is no difference in occurrence between the rural population and people living in cities and there is a clear hereditary disposition for the disease. The frequency of the attacks may be subjected to change in the individual over time. Premenstrual accentuation is common. Migraine has traditionally been regarded as a disease originating from the vessels of the meninges, covering the central nervous system. However, the thinking today is that migraine starts in the central nervous system engaging the brain vessels in the course of the attack. The most common symptoms are headache and nausea often preceded by neurological symptoms like visual flickering, numbness in the face or lips, or drowsiness. The pharmaceuticals most commonly used prophylactically as well as during the attacks are addressing pathological events in the blood vessels.
Epidemiological studies during the 60s in Greenland concluded that migraine was extremely uncommon among the Inuites. Their diet is characterized by containing very high amounts of fish in combination with meat and fat from sea mammals. The fat from these species is very high in the polyunsaturated fatty acids called omega-3 fatty acids. Having dilating effects on the vessels as well as other mode-of-actions important for the prevention of vascular diseases the idea was brought up to test the possible effect on migraine attacks.
Two uncontrolled pilot studies were conducted separately in Sweden and Denmark testing the prophylactic effect of 4 capsules of an omega-3 concentrate providing a dose of 2.4 grams of omega-3 fatty acids daily during three months. All patients continued their normal medication. The Swedish study (1) involved 49 subjects. Eight people did not complete the study protocol leaving 41 for evaluation, 37 women and 4 men. Most of the participants, 33 individuals, had more than 1 attack per week the others 8 in number had not so frequent attacks. Effects before and after 3 months treatment were evaluated by means of a questionnaire.
The medication was well tolerated with only 3 subjects reporting regurgitation with fishy taste. Overall positive results were obtained by the treatment especially in the group with most frequent attacks reporting a reduction in number of migraine attacks by 28% and a reduction in attack intensity by 32%. Both reductions are statistically significant. Those with not so many attacks had lower reductions not reaching statistical significance. The quality-of-life questionnaire revealed that in the group of participants with most frequent attacks 67% were significantly improved while 30% were unchanged. In the other group the percentage improvements were 63% and 37%, respectively.
In the Danish study 41 were recruited but only 35 completed the study protocol. Study duration and dose omega-3 fatty acids were identical with the Swedish study. Eight patients had minor problems related to fishy regurgitation. 21 subjects had frequent attacks and 14 had fewer attacks. 57% of those with frequent attacks and 43% of the others experienced fewer attacks after three months of treatment while 57% and 36%, respectively, had reduced the severity of attacks. For the total group 87% answered that omega-3 medication had improved their migraine condition while 13% did not respond favorably.
In a large study from the US 196 migraine patients were recruited to a study with 6g of omega-3 fatty acids daily or placebo (3). After 4 weeks on placebo the patients were randomly allocated to treatment with omega-3 FA's or placebo during 16 weeks. The study was followed by another 4 weeks placebo period. 96 patients on omega-3 FA's and 87 on placebo completed the protocol. The total number of attacks during the 16-week period of the study was significantly different between the groups with 7.05 in the placebo group and 5,95 in the omega-3 group (p<0.05). However mean intensity and duration of attacks and rescue medication did not differ significantly between the two groups. A very strong placebo effect was observed in the trial with a 45% reduction of the attacks, which could partly explain the negative results on attack intensity.
In conclusion the results of two small pilot studies from two Scandinavian countries and one large US study show somewhat conflicting results. However, the number of attacks were reduced in all three studies confirming the early observations done in Greenland that intake of marine omega-3 fatty acids may positively affect the clinical course of migraine. It is important to realize that the effects of omega-3 fatty acids will increase over time and not be experienced as fast as the pharmaceuticals used on this indication. The dose in the Scandinavian studies was 4 capsules of a 60% omega-3 concentrate (EPAX 5500TG). Patients with severe or frequent attacks would possibly benefit by increasing the dose to 6 capsules daily. Overall the treatment was very well tolerated with only minor adverse effects reported. Marine omega-3 fatty acid concentrates may offer additional therapeutic benefits to migraine patients in combination with anti-migraine pharmaceuticals.
References:
1) Lejnemark NO. Fiskolja hj‰lp mot migr‰n? Migr‰nbladet 1995;20:9.
2) Kan migrÊne pÂvirkes av fiskeolje? Et Âbent studie. MigrÊnenyt 1990;5:20-22.
3) Pradalier A, et al. Failure of omega-3 polyunsaturated fatty acids in prevention of migraine: a double-blind study versus placebo Cephalgia 2001;21:818-822.
*These statements have not been evaluated by the Food and Drug Administration. " |
"By Morten Bryhn, MD, Ph D." |
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