Review Highlights Bidirectional Relationship Between Migraine, Asthma

Migraine is a potential risk factor for asthma and asthma is a potential risk indicator for migraine, authors of a systematic review and meta-analysis concluded.

Approximately 7% to 18% of the world’s population suffers from asthma. Although this condition can be alleviated via inhaled corticosteroid (ICS) or long-acting β-agonists (LABAs), no specific drug that can permanently prevent the recurrence of asthma attacks exists.

It is estimated that 1.04 billion individuals suffer from migraine globally and incidence is frequently comorbid with asthma. This condition has been termed as "acephalic migraine" and "pulmonary migraine."

Common pathophysiologic mechanisms of inflammation and immune dysfunction, shared triggering and environmental factors, and emotional stress or psychological distress could all contribute to the bidirectional association between the 2 conditions.

To better understand the strength of the comorbid relationship between migraine and asthma, researchers conducted a systematic review and meta-analysis of population-based evidence. Articles listed in PubMed, Web of Science, and SCOPUS, including text words and medical subject headings terms "headache" or "migraine" and "asthma" until March of 2020 were reviewed for inclusion in the analysis.

All articles in the review (n = 14) were population-based cohort, case controlled, cross-sectional investigations, included an exposed group of individuals with migraine or asthma and a healthy control group, and reported outcomes in odds ratio (OR), relative risk (RR) or HR. Selection was not restricted based on language of publication.

The 14 articles comprised 1,188,780 subjects, and 1 article reported 2 cohort studies, for a total of 15 studies analyzed. Of the 15 studies, 3 were case-control, 6 were cross-sectional, and 6 were cohort. Articles included studies from the United Kingdom, the United States, Korea, China, Denmark, Norway, Israel, and Sweden. “Five studies relied upon questionnaire or medical records to identify cases of migraine and/or asthma, while 9 relied upon validated International Classification of Headache Disorders (ICHD) or International Classification of Diseases (ICD) codes,” the authors wrote.

Pooled analyses revealed:

• Migraine was associated with a significant increase of prevalent asthma (OR, 1.54; 95% CI, 1.34-1.77)
• Patients with asthma had a significantly increased risk for migraine (RR, 1.42; 95% CI, 1.26-1.60)
• Migraine was associated with a significant increase of prevalent asthma (OR, 1.45; 95% CI, 1.22-1.72)
• Patients with asthma had a significantly increased risk for migraine (HR, 1.47; 95% CI, 1.41-1.52)

“Migraine was associated with 54% increased prevalence and 42% greater risk of asthma, and vice versa, asthma associated with 45% increased prevalence and 47% greater risk of migraine,” researchers wrote.

Because only 1 case-control study was primarily of adolescents and 5 of 6 cohort studies were conducted in Asia, results may not be generalizable, marking a limitation to the review.

Future studies with large samples and different age groups ought to be conducted to clarify the bidirectional relationship between the 2 conditions.

“The bidirectional relationship we found might aid in preventing or identifying people with these 2 diseases. It is necessary to get further information about potential overlapping pathways in pathogenesis, which may facilitate the development of new treatment strategies for migraine and asthma,” the authors concluded.

Reference

Wang L, Deng Z, Zu M, Zhang J, Wang Y. The comorbid relationship between migraine and asthma: a systematic review and meta-analysis of population-based studies. Front Med (Lausanne). Published online January 13, 2021. doi:10.3389/fmed.2020.609528