Ictal, Perictal Migraine Pain Linked With Motor Impairment

During the ictal/perictal phase, migraines can be divided into 2 distinct subgroups based on their clinical and psychophysical characteristics, according to a cluster analysis published in Pain Medicine. The study shows the first group experienced no psychophysical characteristics and the other had increased pain sensitivity, cervical musculoskeletal impairments, and higher disability.

Researchers conducted an observational study which included 2 cohorts of migraine patients, those in the ictal/perictal phase, and those in the interictal phase. Each cluster included patients with episodic or chronic migraines. 

A cluster analysis was performed after assessment of headache frequency, disability, cervical active range of motion (AROM) in flexion, extension, right/left lateral flexion, right/left rotation, pressure-pain threshold (PPT) over: temporalis, 2 cervical areas(C1/C4 vertebral segments), and 2 distal pain-free areas (hand/leg).

In cohort 1, 100 patients were studied and divided into 2 clusters based on their conditions. Cluster 1.1 consisted of patients with no psychophysical impairment, while cluster 1.2 consisted of patients with increased pain sensitivity and cervical musculoskeletal dysfunctions. Cluster 1.1 accounted for 19% of the patients, and Cluster 1.2 accounted for 81%. The study found that cluster 1.1 had a higher percentage of men (P =.037) and higher disability (P =.003) compared with cluster 1.2. Additionally, cluster 1.2 had reduced AROM in flexion, extension, and left/right lateral flexion (P <.037) and lower PPT value in all areas (P <.001) compared with cluster 1.1.

The study analyzed 98 patients in cohort 2 and identified 3 clusters based on their symptoms. Patients in cluster 2.1 did not show any psychophysical impairment, while those in cluster 2.2 had increased pain sensitivity. Patients in cluster 2.3 had both increased pain sensitivity and cervical musculoskeletal dysfunctions. Cluster 2.1 had 18% of the patients, cluster 2.2 had 45%, and cluster 2.3 had 37%. 

Cluster 2.1 also had a higher percentage of men than the other 2 clusters (P =.009). Patients in cluster 2.3 had higher headache frequency and disability compared with those in cluster 2.2 (P <.006) and higher disability compared with those in cluster 2.1 (P =.010). Patients in cluster 2.3 had reduced AROM in all directions compared with those in clusters 2.1 and 2.2 (P <.029). Patients in clusters 2.2 and 2.3 had lower PPT values in all areas than those in cluster 1.1 (P <.001).

“Our study’s results suggest that the same subgroup of patients with increased ictal/perictal pain sensitivity also had ictal/perictal cervical motor impairment, confirming the interaction between these two psychophysical characteristics,” the study authors explain, “This study highlights specific subgroups of migraine patients in different phases of the migraine cycle providing new insight to pave the way for developing personalized and target prophylactic and symptomatic migraine treatments.”

Among several study limitations, the population was recruited from specialized headache centers, and over two-thirds of the patients were excluded for age and other factors.