Central sensitization in migraine is related to restless legs syndrome

Associations between the burdens of comorbid sleep problems, central sensitization, and headache-related disability in patients with migraine

Objective

Sleep disturbances are common in migraine patients and affect quality of life. Central sensitization (CS) is likely to play a role in the increased severity and chronicity of migraine. We hypothesized that the number of comorbid sleep problems would affect headache-related disability through the effects of central sensitization (CS).

Methods

We performed a cross-sectional study including 215 consecutive patients with migraine. Insomnia was defined as a Pittsburgh Sleep Quality Index (PSQI) global score greater than 5. Probable REM sleep behavior disorder (pRBD) was defined as an RBD screening score of 5 or greater. Excessive daytime sleepiness (EDS) was defined as an Epworth Sleepiness Scale score of 10 or higher. Suspected sleep apnea (SA) was defined as patients with snoring or sleep apnea witnessed 3 or more nights a week. CS was assessed by the Central Sensitization Inventory (CSI).

Results

Restless legs syndrome, insomnia, EDS, SA and pRBD were observed in 25.6%, 71.6%, 34.4%, 10.2%, and 21.4%, respectively, of the patients. At least one sleep problem was present in 87.0% of the patients. According to the results of the multinomial logistic regression analysis with no sleep problems as a reference, after we corrected for adjustment factors, the Migraine Disability Assessment (MIDAS) score significantly increased when three or more comorbid sleep problems were present. According to our mediation analysis, an increased number of sleep problems had a direct effect on the MIDAS score after we adjusted for other variables, and the CSI score was indirectly involved in this association.

Conclusion

The present study showed an association between migraine-related disability and the burden of multiple sleep problems, which was partially mediated by CS.

Can calcitonin gene-related peptide monoclonal antibody improve migraine and restless legs syndrome?

BACKGROUND

A significant association between migraine and restless legs syndrome (RLS) has been reported, and their coexistence is not uncommon. We report a patient with concomitant migraine and RLS who showed improvement of both migraine and RLS symptoms after treatment with galcanezumab, a calcitonin gene-related peptide (CGRP) monoclonal antibody.

CASE PRESENTATION

A 47-year-old woman had been treated in our outpatient headache clinic for migraine without aura. She had RLS since childhood and had been treated with dopamine agonists and α2δ ligands. Over the past 2 months, the patient suffered from frequent migraine headaches and worsening RLS symptoms, despite ongoing treatment. Therefore, galcanezumab was started. After 1 month, the number of headache days decreased from 20 to 4, and her score on the International RLS Study Group Rating Scale improved from 38 to 10. Her photo/phono/osmo-phobia were also markedly improved. The efficacy of galcanezumab for both headache and RLS was sustained over 5 months.

CONCLUSION

We report a case of improvement of both migraine and RLS after treatment with CGRP monoclonal antibody. Additional studies are needed to clarify how CGRP antagonism affects RLS symptoms in patients with migraine and RLS comorbidity.

Central Sensitization in Migraine: A Narrative Review

Central sensitization (CS) is an increase in the responsiveness of nociceptive neurons in the central nervous system to their normal afferent input. As a result, even minor irritation can induce severe pain, leading to the chronicity and severity of various diseases, such as neurological disorders. CS is associated with migraine, which is a major neurological disorder that inflicts a high disability in daily life. Specifically, CS is thought to be involved in the pathogenesis of cutaneous allodynia as well as chronification of migraine. In this article, we reviewed the association between CS and migraine, including pathophysiological aspects and evidence from clinical studies. We suggest that appropriate screening and management of CS in migraine could further improve the quality of life of migraine patients.

Are menstrual symptoms associated with central sensitization inventory? A cross-sectional study

BACKGROUND

Dysmenorrhea is a prevalent pain condition that affects women of reproductive age, who are monthly exposed to this pain, usually until they reach the adult age, or even after that, which can predispose them to Central Sensitization. The present study aimed to observe the association between menstrual characteristics and central sensitivity symptoms in women.

METHODS

Cross-sectional study. Brazilian women (n=10,402) answered an online form comprised of questions regarding their gynecological history, the Numerical Rating Scale for pain and the Central Sensitization Inventory, part A. For the analysis, we separated women into two groups: Central Sensitivity Symptoms group (n=5,200) and No-Central Sensitivity Symptoms group (n=5,202). We performed a binary logistic regression with the backward insertion method for the variables with p<0.05 in the bivariate analysis between groups. The significance level was set at 5%.

RESULTS

Prevalence of dysmenorrhea was 67.3%, and 32.2% of women in the Central Sensitivity Symptoms group reported pain >8 during their menstrual period. The logistic regression showed that greater levels of menstrual pain (Odds Ratio 1.12), gynecological diseases (Odds Ratio 1.51), presence of dysmenorrhea since adolescence (Odds Ratio 1.20) and irregular menstrual cycles (Odds Ratio 1.47) increased the likelihood of women presenting with Central Sensitivity Symptoms (p<0.05 for all comparisons).

CONCLUSIONS

The present study shows that Central Sensitivity Symptoms are present in about 50% of women and are associated with menstrual characteristics such as dysmenorrhea-related pain intensity, cycle regularity, presence of dysmenorrhea since adolescence accompanied by gynecological diseases.

SIGNIFICANCE

Central sensitivity symptoms occur in 50% of women, and are more present in women with dysmenorrhea. They are associated with cycle regularity, presence of dysmenorrhea since adolescence, and gynecological diseases.

LIMITATIONS

Women that suffer from dysmenorrhea and of higher socioeconomic and educational levels may have been more propense to respond to the invitation; as such, the findings of the present study should be carefully interpreted.

Exploring the contributing factors to multiple chemical sensitivity in patients with migraine

Objective

Multiple chemical sensitivity (MCS) is a form of chemical intolerance in which various systemic symptoms are triggered by exposure to a variety of chemical substances. Although migraine has been associated with central sensitivity syndrome, the relationship between MCS and migraine has not been studied. We assessed the frequency of MCS and its related factors in patients with migraine.

Methods

We performed a cross‐sectional study that included 95 patients (14 M/81 F; age, 45.4 ± 12.4 years) out of 100 consecutive patients with migraine from our outpatient headache clinic. MCS was defined as having a combination of Q1 ≥ 30, Q3 ≥ 13, and Q5 ≥ 17 on the quick environment exposure sensitivity inventory (QEESI; Japanese version). Central sensitization inventory‐A scores >40 were considered an indication of central sensitization. Headache‐related disability and psychological distress were evaluated with the Migraine Disability Assessment score (MIDAS) and Kessler Psychological Distress Scale (K6), respectively.

Results

MCS was identified in 20% of patients with migraine; however, none had previously been diagnosed with MCS. The MCS‐positive group had higher rates of photophobia, osmophobia, visual aura, sensory aura, and central sensitization and higher MIDAS and K6 scores than the MCS‐negative group. A logistic regression analysis showed that osmophobia, sensory aura, and central sensitization were significant contributors to MCS.

Conclusion

We showed that MCS was observed in 20% of patients with migraine, and our study results may indicate a possible association of MCS with central sensitization and hypersensitivity‐related symptoms in patients with migraine.

Cranial autonomic symptoms in migraine are related to central sensitization: a prospective study of 164 migraine patients at a tertiary headache center

Background

Cranial autonomic symptoms (CASs) during migraine attacks are reported to be quite common regardless of ethnicity. In our previous study investigating 373 migraineurs, we found that 42.4% of them had CASs. The patients with CASs more frequently had cutaneous allodynia than did those without CASs, and we speculated that CASs were associated with central sensitization. The present study searched for substantial evidence on the relationship between CASs and central sensitization in migraine patients.

Methods

This was a prospective cross-sectional study. We studied a new independent cohort of 164 migraineurs who presented to the Tominaga Hospital Headache Center from July 2018 until December 2019. The clinical features of CASs according to the criteria in ICHD-3 (beta) were investigated. We also evaluated central sensitization based on the 25 health-related symptoms utilizing the validated central sensitization inventory (CSI), and each symptom was rated from 0 to 4 resulting a total score of 0–100.

Results

The mean age was 41.8 (range: 20 to 77) years old. One hundred and thirty-one patients (78.9%) were women. Eighty-six of the 164 (52.4%) patients had at least 1 cranial autonomic symptom. The CSI score of the patients with ≥3 CASs reflected a moderate severity and was significantly higher than in those without CASs (41.9 vs. 30.7, p = 0.0005). The score of the patients with ≥1 conspicuous CAS also reflected a moderate severity and was significantly higher than in those without CASs (40.7 vs. 33.2, p = 0.013). The patients in the CSI ≥40 group had lacrimation, aural fullness, nasal blockage, and rhinorrhea, which are cranial autonomic parasympathetic symptoms, significantly more frequently than those in the CSI < 40 group.

Conclusions

Migraine patients with CASs showed significantly greater central sensitization than those without such symptoms. In particular, cranial parasympathetic symptoms were more frequent in centrally sensitized patients than in nonsensitized patients, suggesting that cranial parasympathetic activation may contribute to the maintenance of central sensitization.

Trial registration

This study was retrospectively registered with UMIN-CTR on 29 Aug 2020 (UMIN000041603).

A large-scale population-based epidemiological study on the prevalence of central sensitization syndromes in Japan

A cross-sectional study of 21,665 Japanese residents was performed to investigate the prevalence of central sensitization syndromes (CSS). CSS were assessed using the Central Sensitization Inventory (CSI-A). CSS were defined as a CSI-A score of 40 or higher. Age, sex, district, 10 CSS-related diseases (CSI-B), lifestyle, and mental factors were rated in a self-reported survey. The prevalence of CSS and its relationship with potential factors were examined by sex using descriptive and logistic regression models. The prevalence of CSS was 4.2% in all participants and was significantly higher in women (4.9%) than in men (2.7%). Adjusted odds ratios correlated with CSS for an age of 80–97 years versus 60–79 years (2.07 and 2.89), one or more CSI-B diseases (3.58 and 3.51), few sleeping hours (2.18 and 1.98), high perceived stress (5.00 and 4.91), low (2.94 and 2.71) and high (0.45 and 0.66) resilience versus moderate resilience, and exercise habits (0.68 and 0.55) in men and women (all P < 0.05). The relationship between CSS and age 20 and 59 years, ex-smokers, coffee intake, and alcohol intake differed by sex. The prevalence of CSS was estimated to be low in the healthy population. CSS correlated with CSS-related diseases and some positive and negative factors.