Patients who experience transformation of episodic migraine to chronic migraine are more likely to have high-frequency episodic migraine and depression, a study in Cephalalgia suggests. Conversely, the study found that having an annual household income ≥$50,000 may protect against this transformation.
The study was an electronic literature review and meta-analysis of 11 studies that reported predictors or risk factors for new-onset chronic migraine in patients with episodic migraine. Only studies published between 2004 and 2018 were included in the review and subsequent analysis. In the pooled meta-analysis portion of the study, the investigators assessed migraine data for a total of 65,775 patients.
Several predictors or risk factors for chronic migraine were reported, including age, sex, body mass index, annual household income, headache days, diet, family headache history, and disability. Depression was significantly associated with an increased risk for chronic migraine in the pooled analysis (assessed by Patient Health Questionnaire-9; risk ratio [RR], 1.58; 95% CI, 1.35-1.85; P <.00001).
Other variables associated with an increased risk for new-onset chronic migraine included monthly headache day frequency of ≥5 (RR, 3.18; 95% CI, 2.65-3.82; P <.00001), monthly headache day frequency of ≥10 (RR, 5.95; 95% CI, 4.75-7.46; P <.00001), and cutaneous allodynia (RR, 1.40; 95% CI, 1.23-1.59; P <.00001). Patients with an annual household income of ≥$50,000, however, had a decreased risk for chronic migraine (RR, 0.65; 95% CI, 0.54-0.79). Medication overuse also predicted new-onset chronic migraine in a random-effects model (RR, 8.82; 95% CI, 2.88-27; P <.00001).
Limitations of the analysis were the inclusion of observational study data and the inclusion of mostly US-based studies.
As a result of their findings, the researchers of the meta-analysis suggest “healthcare professionals should remain vigilant for factors that may increase risk of progression to chronic migraine among people with [episodic migraine], including high frequency headache, medication overuse and depression, and treat these conditions when they encounter them.”
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Xu J, Kong F, Buse DC. Predictors of episodic migraine transformation to chronic migraine: a systematic review and meta-analysis of observational cohort studies [published online October 21, 2019]. Cephalalgia. doi: 10.1177/0333102419883355