Q&A for Primary Care: Migraine May Lead to Certain Diseases

We’ve long known that migraine is an insidious disease. Patients with a variety of existing illnesses — atopic disorders, cardiovascular diseases, and sleep and/or psychiatric disorders — are at a risk for migraine. The revelation that migraine, a neurologic, life-altering disorder, has comorbidities isn’t new. What is new, said Stephen Landy, MD, a neurologist and headache specialist, is that certain diseases and disorders can predispose patients to migraine — instead of the other way around, something new research has now shown.

Here, Landy, director of the Tupelo Headache Center, Tupelo, Mississippi, and clinical professor in the Department of Neurology at The University of Tennessee Health Science Center, Memphis, Tennessee, discussed the implications of this study, recently published in the European Journal of Neurology.

Stephen Landy, MDMedscape Medical News: Can you explain what this paper says?

Landy: The authors combed through 38 studies, based on registry, insurance, and/or cohort data, looking for significant risk for migraine among various preexisting conditions. Atopic conditions were strongly associated with migraine development. New-onset migraine was also strongly connected to psychiatric and sleep disorders.

In fact, asthma and depression were found to be bidirectional — one can be associated with the other and vice versa. The cardiovascular connection also could be bidirectional, meaning a connection or interaction exists between the entities in a two-way manner.

Medscape Medical News: Were you surprised by these findings?

Landy: No. Preexisting disease states can activate migraine and can present before migraine does.

Medscape Medical News: Migraine already has been connected with many diseases, correct?

Landy: Yes, many, at least 24, including stroke, epilepsy, and endometriosis.

Medscape Medical News: Why do you think there are so many migraine comorbidities?

Landy: The body has interconnecting vascular and neurologic systems: Neurovascular, cardiovascular, gastrointestinal, pulmonary, and so on. And migraine is heterogeneous: It can follow different pathways to the brain’s pain receptors, which is why all migraine medications are not effective on all patients, including the calcitonin gene–related peptide inhibitors.

Medscape Medical News: Will everyone who develops one of these disorders develop migraine?

Landy: No. If a person doesn’t have a predisposition to migraine, it won’t develop.

Medscape Medical News: Please explain that.

Landy: A shared gene, or genes, between the comorbidity and migraine is key to development. A comorbidity develops frequently due to genetic, environmental, and social influences and behavior. So if someone doesn’t have that genetic predisposition, they are less likely to develop migraine but could have migraine-like symptoms because these symptoms may activate a response in the neural network, similar to migraine.

Medscape Medical News: What concerns you about these authors’ findings?

Landy: A main concern is that patients may develop migraine progression, from episodic — fewer than 14 monthly headache days— to more than 15 monthly headache days, with 8 of those 15 considered to be migraine. Migraine frequency can increase if not properly diagnosed and treated. Once it becomes chronic, the patient’s quality of life will be sorely affected: Missed work days, missed social events, let alone dealing with the pain.

Another concern is that a missed migraine diagnosis or a misdiagnosis in a patient with comorbidities becomes more critical because both diseases may progress without proper treatment. The longer one disease is left inappropriately treated or not diagnosed, a concern is the odds of developing migraine increase.

Patients may rely on over-the-counter (OTC) medications to deal with their headache pain. The more they rely on OTC medications, the less effective those medications may be. The brain is increasingly overreacting to the pain stimuli. There is an exaggeration of response because the incoming stimuli increasingly activates the trigeminal nociceptive system, which transmits sensory information, like pain. This constant activation can make a patient more refractory to treatment.

Medscape Medical News: What should primary care physicians (PCPs) do for their patients with migraine?

Landy: First, all patients, especially women, as more women report migraine, should be screened for migraine. Physicians, especially general practitioners, need to take a complete and comprehensive history. Migraine has a genetic component, so getting a family history is critical. An important question physicians should ask is whether the patient is experiencing cutaneous allodynia. Cutaneous allodynia is a surrogate clinical marker of central sensitization. So ask the patient if it hurts to take a shower, to comb their hair, and to shave because these activities shouldn’t hurt. It is an augmentation of pain perception for the patient.

Also ask about depression, anxiety, noncephalic pain and fibromyalgia, and sleep disorders, especially if the patient has obesity. Gastrointestinal disorders should be a consideration in all patients with migraine. Once the physician diagnoses migraine, consider referring the patient for further headache evaluation.

Medscape Medical News: What is the takeaway for this paper?

Landy: This paper is likely the first of its kind to identify patients with cardiovascular and pulmonary issues and so on with new-onset migraine. This paper shows that PCPs and specialists should screen every patient for migraine. We are trying to figure out a way to evaluate and diagnose comorbidities in a better way. The evidence this paper produced is the reason we should do that.