Fluctuations in local and widespread mechanical sensitivity throughout the migraine cycle: a prospective longitudinal study

DOI: https://doi.org/10.1186/s10194- 020- 1083- z

Abstract-Summary People with migraine have localised (i.e., cephalic) mechanical sensitivity.

There is uncertainty regarding widespread (i.e., extra-cephalic) mechanical sen-

sitivity and variations in mechanical sensitivity throughout the migraine cycle.

This study aimed (1) to comprehensively assess mechanical sensitivity in both cephalic and extra-cephalic regions during the preictal, ictal, postictal and interictal phases; and (2) to compare these findings with mechanical sensitivity at correspond- ing time-points and locations in healthy participants.

Pressure pain thresholds were evaluated in three cephalic regions (temporalis, upper trapezius and C1 paraspinal muscles) and two extra-cephalic regions (exten- sor carpi radialis and tibialis anterior muscle) with a digital algometer during the

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four phases of the migraine cycle in people with migraine and at corresponding intervals and locations in healthy participants.

People with migraine had increased mechanical sensitivity in cephalic and extra- cephalic regions in all phases of the migraine cycle compared to healthy participants.

People with migraine have localised as well as widespread mechanical sensitiv-

ity compared to healthy participants.

Extended: People with migraine were recruited from primary healthcare centres

between April 2017 and April 2018.

People with migraine experience mechanical sensitivity throughout the four

phases of the migraine cycle compared to healthy participants.

This study aimed (1) to comprehensively assess mechanical sensitivity during the preictal, ictal, postictal and interictal phases in people with migraine in both cephalic and extra-cephalic regions, and (2) assess differences in mechanical sensi- tivity between people with migraine and healthy participants in both cephalic and extra-cephalic regions at corresponding time points.

Our findings support the view that central sensitization mechanisms are involved

in people with migraine.

Introduction A recent study, not included in the reviews, assessed cyclic changes in mechanical sensitivity in the cephalic region in people with migraine, and found no statistically significant differences between the interictal, preictal and ictal phase [285].

Based on the hypothesis that people with migraine have established central sen- sitization which may exacerbate due to extra temporary failure of supraspinal inhi- bition in addition to possible peripheral mechanisms [286, 287], it is expected that sensitization is a fluctuating phenomenon with increasing mechanical sensitivity from the interictal to the preictal phase, and subsequently to the ictal phase.

This study aimed (1) to comprehensively assess mechanical sensitivity during the preictal, ictal, postictal and interictal phases in people with migraine in both cephalic and extra-cephalic regions, and (2) assess differences in mechanical sensi- tivity between people with migraine and healthy participants in both cephalic and extra-cephalic regions at corresponding time points.

Methods Baseline measurements were performed in the interictal phase and consisted of completion of various questionnaires and the assessment of mechanical sensitivity via determination of pressure pain thresholds (PPTs).

The inventory has good test-retest reliability in people with chronic pain (ICC =

0.88) and healthy participants (ICC = 0.91) [288].

All participants rated their headache pain intensity before each measurement on

a numeric pain rating scale (NPRS).

In case of bilateral migraine, the most prevailing side of the headache was mea-

sured first.

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Healthy participants were measured accordingly with equal time intervals

between the measurements as the matched person with migraine.

A sample size calculation was performed based on the effect size and standard deviation (SD) of a study that compared PPTs at the trapezius muscle between peo- ple with migraine and healthy participants [289].

Participants who did not attend the four measurement sessions were excluded

from the statistical analysis.

Results Fifty-one people with migraine were assessed for eligibility criteria of whom 29 commenced the study.

There were no significant differences in participant characteristics between peo- ple with migraine who completed all sessions and those who were excluded during the study (p > 0.136).

Similar patterns with decreasing PPTs from the interictal to the preictal and sub- sequent to the ictal phase were observed in people with migraine and were most pronounced in the cephalic region at the dominant side.

Discussion Throughout the four phases of the migraine cycle, people with migraine have mechanical sensitivity in cephalic and extra-cephalic regions compared to healthy participants.

The findings of lower PPT values in people with migraine compared to healthy participants in the interictal phase in the cephalic region are in line with previous systematic reviews [290, 291].

One of these studies also found lower PPTs in the interictal phase in extra- cephalic regions (tibialis anterior muscle and second metacarpal) in people with migraine compared to healthy participants [292].

The other study measured PPTs at the forearm in the interictal phase in women with menstrual migraine and found no significant differences compared to healthy participants [293].

Mechanical sensitivity can also fluctuate throughout the menstrual cycle with higher pain thresholds in the luteal phase compared to the follicular and ovulatory phase in people with migraine and healthy participants without significant differ- ences between the groups [293].

Conclusions People with migraine experience mechanical sensitivity throughout the four phases of the migraine cycle compared to healthy participants.

Acknowledgement A machine generated summary based on the work of Scholten-Peeters, Gwendolyne G.  M.; Coppieters, Michel W.; Durge, Tom S.  C.; Castien, René F. 2020  in The Journal of Headache and Pain.

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Clinical relevance of depressed kynurenine pathway in episodic migraine patients: potential prognostic markers in the peripheral plasma during the interictal period