The relationship between migraine and infant colic: a systematic review and meta-analysis.

CONTEXT: Infant colic is a common and distressing disorder of early infancy. Its etiology is unknown, making treatment challenging. Several articles have suggested a link to migraine. OBJECTIVE: The objective of this article was to perform a systematic review and, if appropriate, a meta-analysis of the studies on the relationship between infant colic and migraine. DATA SOURCES: Studies were identified by searching PubMed and ScienceDirect and by hand-searching references and conference proceedings. STUDY SELECTION: For the primary analysis, studies specifically designed to measure the association between colic and migraine were included. For the secondary analysis, studies that collected data on colic and migraine but were designed for another primary research question were also included. DATA EXTRACTION: Data were abstracted from the original studies, through communication with study authors, or both. Two authors independently abstracted data. MAIN OUTCOMES AND MEASURES: The main outcome measure was the association between infant colic and migraine using both a fixed-effects model and a more conservative random-effects model. RESULTS: Three studies were included in the primary analysis; the odds ratio for the association between migraine and infant colic was 6.5 (4.6-8.9, p < 0.001) for the fixed-effects model and 5.6 (3.3-9.5, p = 0.004) for the random-effects model. In a sensitivity analysis wherein the study with the largest effect size was removed, the odds ratio was 3.6 (95% CI 1.7-7.6, p = 0.001) for both the fixed-effects model and random-effects model. CONCLUSIONS: In this meta-analysis, infant colic was associated with increased odds of migraine. If infant colic is a migrainous disorder, this would have important implications for treatment. The main limitation of this meta-analysis was the relatively small number of studies included.