Date of Award
Selective Evidence-Based Medicine Review
Master of Science in Health Sciences - Physician Assistant
John Cavenagh, PhD, PA-C
OBJECTIVE: The objective of this selective EBM review is to determine whether or not individualized diet restriction based on IgG against foods is effective as migraine prophylaxis in adults who suffer from migraines.
Study Design: Systematic review of three English language primary studies, published between 2009-2011.
DATA SOURCES: Two randomized controlled trials and one case report published after 1996 comparing migraine frequency before and after diet elimination based on IgG against foods were obtained using PubMed and Cochrane databases.
OUTCOMES MEASURED: Migraine frequency, recorded by patients in a headache diary throughout the duration of the diet, was the primary outcome measured. Subjects reported baseline migraine frequency and characteristics through a baseline diet phase6 or through a focused questionnaire,8 and results were compared after the completion of the diet phase.
RESULTS: None of the studies reported any intervention-related adverse events or side effects. Alpay and colleagues showed a statistically significant reduction in the number of headache days and migraine attacks,6 with a NNT of 34. Mitchell and colleagues showed a statistically significant reduction in migraine frequency at week 4 of the elimination diet, but after a full 12 weeks, the difference was not statistically significant.8 In a case report by Nelson-Dooley,9 the patient showed a subjective reduction of migraine frequency compared to baseline.
CONCLUSIONS: Some reduction of migraine frequency was demonstrated by all three studies, however the evidence is inconclusive. This can be attributed to a statistically significant reduction in migraine frequency but a high NNT in the study by Alpay and colleagues, conflicting evidence (migraine frequency at 4 weeks vs. 12 weeks) in the study by Mitchell and colleagues, and the multiple simultaneous treatment interventions and subjective results in the case report by Nelson-Dooley. Larger studies with a longer intervention period (>4 weeks), emphasizing more controlled diets/meal plans and elimination of confounding factors may clarify these inconsistent study results. Thus, future study is warranted to evaluate prophylactic diet elimination based on IgG against foods for migraine frequency reduction before routine use is recommended.
Cicioni, Jessica, "Is Individualized Diet Restriction Based on IgG Against Foods Effective for Reducing Migraine Frequency in Adults Who Suffer from Migraines?" (2013). PCOM Physician Assistant Studies Student Scholarship. 129.