A noteworthy new area of migraine research has led to the inclusion of infantile colic in the 2013 version of the International Headache Society’s guidelines, The International Classification of Headache Disorders, 3rd Edition (ICHD-III).1 It is important to clarify that infantile colic is not currently recognized by the ICHD-III as an actual migraine type, but rather an “episodic syndrome that may be associated with migraine.” Infantile colic is listed in the appendix of the ICHD-III, which means that researchers will continue to investigate its connection to migraine over the next few years. If enough evidence is gathered, then it may be included as an official migraine classification in the next edition of the guidelines.
Infantile colic can cause an otherwise healthy baby to cry frequently, excessively, and inconsolably for no clearly apparent reason. It is quite common, affecting around 20% of infants from newborns up to a few months of age. However, its cause is not yet well understood and there is no standard, effective treatment that parents can use to help an infant with colic. Although it usually disappears after a few months and has no lasting negative effects, the infant’s discomfort can be very upsetting for parents who feel powerless to help their child.
Diagnosing infantile colic
According to the ICHD-III, infantile colic is characterized by recurring episodes of irritability, fussing, and/or crying from birth until the age of 4 months. The infant’s distress is not attributable to any other cause (eg, “failure to thrive”). These episodes must last for at least 3 hours a day and happen at least 3 days a week for 3 or more weeks. These conditions are in keeping with the standard description of infantile colic that has been widely accepted for more than 60 years.2
Probable causes of infantile colic episodes
Infantile colic is generally described as a pain syndrome that may have multiple causes. One of the most difficult issues with infantile colic is figuring out the exact symptoms that are causing the infant’s distress, because the baby is unable to communicate directly. Stomach pain, nausea, and headache - alone or in combination - are all thought to be common reasons for the crying episodes.3
Gastrointestinal discomfort is often believed to be the primary source of the infant’s distress. However, there is a relatively new suggestion that the stomach pain and nausea may have their own underlying cause: a very early form of childhood migraine.
Possible link between migraine and infantile colic?
Stomachache, nausea, and head pain are common symptoms experienced by infants with colic, as well as by older children and adults with migraine. Researchers are working on a theory that these symptoms of infantile colic are actually the effects of a migraine attack. If a direct connection between infantile colic and migraine can be established, it could provide an important new window into further understanding the genetics of migraine and how it develops through infancy, childhood, and adulthood.
A 2013 European study investigated 208 children between the ages of 6-18 years who were diagnosed with migraine.2 Each child’s parents completed a questionnaire about whether the child had a history of colic as an infant. The results revealed that more than 70% of the children with migraine (with or without aura) had experienced infantile colic. Based on this data, they concluded that there is a significant link between the two conditions. The children with migraine had a higher chance of having had infantile colic than either children without migraine or children diagnosed with tension-type headache. Research has also shown that a mother with migraine is 2.5 times as likely to have a baby with colic. Similarly, men with migraine are about twice as likely to have infants with colic.1
Causes and treatment
A disturbed sleep pattern is often linked to episodes of infantile colic, and sleep disruption is also a known migraine trigger for adults and older children. Some researchers think that infantile colic might involve a type of migraine that is triggered during a phase of development when sleep cycles are still irregular and often disrupted.3 During the first few months of life, an infant’s body is working to develop the circadian rhythms that control regular cycles of sleeping and waking. Around the age of 3-4 months, when sleep patterns become more routine, infantile colic often disappears.
Common ways of treating infantile colic include medication, dietary changes such as special types of formula feeding, behavioral techniques, and alternative medicines.2 Unfortunately, most of these therapies do not have strong scientific evidence for their effectiveness.4 The only strategy that has some proven benefit is to decrease the infant’s levels of stimulation and encourage relaxation during colic episodes. Interestingly, this is also known to be a beneficial way to treat adults during migraine attacks.2
Strategies that focus on treating infantile colic as an allergy-related and/or digestive-system issue are sometimes helpful, but very often ineffective.2 If colic is actually an early form of migraine, it would help to explain why that kind of treatment does not work consistently.3 Future research should help to pave the way for more effective treatment options for infantile colic, which would be hugely helpful for families trying to deal with this little-understood condition.