LOS ANGELES—Asthma is associated with an increased risk for transformation from episodic migraine to chronic migraine, according to data presented at the 56th Annual Scientific Meeting of the American Headache Society. Patients with the most severe respiratory symptoms have the highest risk for transformation to chronic migraine.
“Mast cell degranulation or parasympathetic hyperactivity, as encountered with asthma, might predispose [an individual] to the future onset of chronic migraine,” said Vincent Martin, MD, Professor of Medicine at the University of Cincinnati. Migraine and asthma are thought to involve inflammatory and neuronal mechanisms, he added.
Vincent Martin, MD
The AMPP Study
The findings are from an analysis of data from the American Migraine Prevalence and Prevention (AMPP) study. Dr. Martin and colleagues included participants who completed the 2008 AMPP survey and met the International Classification of Headache Disorders-3 beta criteria for episodic migraine in that year. In 2008, all subjects completed the six-item asthma questionnaire from the European Community Respiratory Health Survey (ECRHS), the Migraine Disability Assessment Scale (MIDAS), the Patient Health Questionnaire Depression module, and the Allodynia Symptom Checklist-12. Participants also completed the MIDAS in 2009.
Following the ECRHS, the researchers defined asthma as a dichotomous variable using a predefined cut-score. They developed Respiratory Symptom Severity (RSS) categories based on the number of positive responses a person gave to the ECRHS. Mild symptoms were defined as one or two positive responses, moderate as three or four positive responses, and severe as five or six positive responses. The primary outcome measure of the analysis was new-onset chronic migraine in 2009.
Mean MIDAS Score Was Higher for Patients With Asthma
A total of 4,446 patients with episodic migraine in 2008 were included in the analysis. Of these people, 746 had asthma, and 3,700 did not. Approximately 45% of patients with asthma earned less than $30,000 per year, compared with 25% of patients without asthma. Patients with asthma also were less likely to earn more than $50,000 per year, compared with patients without asthma.
In addition, mean MIDAS score was 12.2 among people with asthma, compared with 7.36 for people without asthma. Approximately 34% of participants with asthma had depression, compared with 15% of participants without asthma. About 65% of patients with asthma had cutaneous allodynia, compared with 53% of patients without asthma.
The odds ratio for chronic migraine onset, adjusted for sociodemographic factors and clinical characteristics, was 1.9 among individuals with asthma, compared with patients without asthma. People with a severe RSS grade had a statistically significant increase in the risk of chronic migraine onset with an odds ratio of 2.8, compared with subjects without respiratory symptoms. Individuals with mild and moderate respiratory symptoms also had an increased risk of chronic migraine onset, but the increase was not statistically significant.
“Our results indicate that asthma may be one of the most potent risk factors for the transformation of episodic to chronic migraine,” Dr. Martin told Neurology Reviews. “Clearly, more research needs to be done to further define the mechanisms through which asthma increases the frequency of migraine.”
—Erik Greb