Prevalence of restless legs syndrome in individuals with migraine: a systematic review and meta-analysis of observational studies

Sleep Symptoms in Migraine

PURPOSE OF REVIEW

To review replicated and highlight novel studies of sleep in children and adults with episodic and chronic migraine.

RECENT FINDINGS

Attack-related sleep symptoms are most common in the prodrome and may represent early activation of the hypothalamus rather than migraine triggers. Interictally, patients with migraine report poor sleep quality and high rates of insomnia symptoms. Cognitive behavioral therapy for insomnia in adults and adolescents with chronic migraine and comorbid insomnia results in significant improvement on their headache burden. Thus far, objective studies report that migraine per se is a not associated with sleep apnea. At the present time, there is minimal evidence that migraine is under circadian influence. The current body of evidence suggests that the insomnia symptoms and poor sleep quality commonly reported by patients with migraine are not attack-related but occur interictally and are a marker of worsening disease. The development of clinical guidelines to approach sleep symptoms and expansion of CBT-I trials in those with episodic migraine would be clinically valuable.

Effects of Dietary Supplementation in Patients with Restless Legs Syndrome: A Systematic Review

Restless legs syndrome (RLS) is a common neurological disorder. It disrupts sleep and well-being and is often associated with other conditions. This review examines the potential of dietary supplements to manage RLS symptoms and reduce reliance on medications. A total of 10 randomized clinical trials involving 482 participants were analyzed, focusing on the impact of various supplements on symptom severity, sleep quality, and daytime sleepiness. Findings suggest some supplements may have positive results. Magnesium oxide and vitamin B6 significantly improved sleep quality and RLS symptoms, with magnesium showing greater effectiveness. Vitamin D supplementation did not show significant benefits. Oral iron has promising results, indicating potential efficacy but issues related to compliance and absorption. Both vitamins C and E positively affect RLS symptoms, likely due to their antioxidant properties. Valerian improved RLS and sleep but did not show a statistically significant improvement. Despite these encouraging results, a high risk of bias was noted in half of the studies, emphasizing the need for more rigorous research. Overall, this review suggests that dietary supplements may be a promising approach to managing RLS. However, further investigation is required to confirm the efficacy and safety.

Prevalence of restless legs syndrome in adults with epilepsy: A systematic review and meta-analysis of observational studies

INTRODUCTION

Epilepsy is a common neurological disorder that significantly contributes to the worldwide disease burden. Restless legs syndrome is sleep-related movement disorder that causes uncomfortable sensations in the legs with an irresistible urge to move them. The aim of this study is to comprehensively assess the current evidence to estimate the prevalence of restless legs syndrome (RLS) in adults with epilepsy (AWE) and to compare it to healthy controls.

METHODS

PubMed, Medline, Scopus, and Web of Science databases were searched for observational studies reporting the prevalence of RLS in AWE. The modified Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of the studies. Comprehensive Meta-Analysis software (version 3.0) was used to perform data analysis. The heterogeneity of the studies was assessed using the I2 index. The pooled prevalence of RLS in AWE and the odds ratio were calculated based on the random-effect model. Sensitivity analysis was assessed. A funnel plot and Egger's test were used to investigate publication bias. Subgroup analysis and univariate meta-regression analysis were done.

RESULTS

Based on the analysis of 17 studies (2262 AWE patients), the prevalence of RLS was 14.9 % (95%CI, 10.4%-21 %). This rate was highest in the Americas (35.3 %; 95 % CI: 19.7-54.9 %) and lowest in Asian countries (11.6 %). The risk of RLS was significantly higher in AWE patients compared to health controls (12 studies, OR = 2.09; 95 % CI: 1.53-2.85, I2 = 91.69 %, P < 0.001). subgroup analysis showed Variations in RLS rates between studies depending on quality scores, methodology, and diagnostic criteria. The funnel plot and Egger's test suggest there was publication bias. Sensitivity analysis showed that none of the studies on their own significantly affected the results.

CONCLUSIONS

This meta-analysis provides the first pooled estimate of RLS prevalence in AWE. RLS occurs in 15 out of every 100 AWE patients, and the risk is high compared to healthy controls. However, the findings need to be confirmed in future studies owing to limitations in the analysis and study design.

Intervening in the Premonitory Phase to Prevent Migraine: Prospects for Pharmacotherapy

Migraine is a common brain condition characterised by disabling attacks of headache with sensory sensitivities. Despite increasing understanding of migraine neurobiology and the impacts of this on therapeutic developments, there remains a need for treatment options for patients underserved by currently available therapies. The first specific drugs developed to treat migraine acutely, the serotonin-5-hydroxytryptamine [5-HT1B/1D] receptor agonists (triptans), seem to require headache onset in order to have an effect, while early treatment during mild pain before headache escalation improves short-term and long-term outcomes. Some patients find treating in the early window once headache has started but not escalated difficult, and migraine can arise from sleep or in the early hours of the morning, making prompt treatment after pain onset challenging. Triptans may be deemed unsuitable for use in patients with vascular disease and in those of older age and may not be effective in a proportion of patients. Headache is also increasingly recognised as being just one of the many facets of the migraine attack, and for some patients it is not the most disabling symptom. In many patients, painless symptoms can start prior to headache onset and can reliably warn of impending headache. There is, therefore, a need to identify therapeutic targets and agents that may be used as early as possible in the course of the attack, to prevent headache onset before it starts, and to reduce both headache and non-headache related attack burden. Early small studies using domperidone, naratriptan and dihydroergotamine have suggested that this approach could be useful; these studies were methodologically less rigorous than modern day treatment studies, of small sample size, and have not since been replicated. The emergence of novel targeted migraine treatments more recently, specifically calcitonin gene-related peptide (CGRP) receptor antagonists (gepants), has reignited interest in this strategy, with encouraging results. This review summarises historical and emerging data in this area, supporting use of the premonitory phase as an opportunity to intervene as early as possible in migraine to prevent attack-related morbidity.

Sleep Symptoms and Disorders in Episodic Migraine: Assessment and Management

PURPOSE OF REVIEW

We review research on sleep symptoms and disorders in patients with episodic migraine and propose a framework for evaluating sleep symptoms in this patient population.

RECENT FINDINGS

Patients with episodic migraine consistently report poorer sleep on validated self-reports compared to those without migraine. In polysomnographic studies, children with migraine have objectively shorter sleep duration and lower percentage of REM sleep interictally. Prospective actigraphy studies in adults and children suggest that there are no significant changes in sleep duration, efficiency, or quality in the night before or after a migraine attack. The relationship between sleep and migraine is multifaceted. Patients with episodic migraine report poorer sleep and have higher risk of some sleep disorders, including insomnia, sleep-related bruxism, and restless legs syndrome. Sleep screening questions may be incorporated into headache evaluations. Care should be taken to avoid headache medications that may exacerbate sleep symptoms. Evidence-based treatments for insomnia may be initiated while patients await CBT-I. Further studies are needed to assess whether treatment of comorbid sleep disorders results in improvement in migraine-related burden in those with episodic migraine.

Microstructural changes of basal ganglia in migraine with restless legs syndrome: findings from a neuroimaging study

In this study, it is planned to investigate the integrity of the basal ganglia structures in migraineurs with restless legs syndrome (RLS) to explore this relationship. In this study, 58 patients who were diagnosed migraine and 51 healthy controls (HCs) were included. Patients diagnosed with migraine were divided into two groups: Group I (migraine without RLS) and Group II (migraine with RLS). The integrity of basal ganglia was evaluated with region of interest diffusion tensor imaging method which allows us to assess microstructural changes of the tissue. The mean age of the patients was 35.98 ± 7.92 years, and the mean age of the HCs was 33.84 ± 11.06. 84.5% (n = 49) of the patients were female and 15.5% (n = 9) were male. 82.4% (n = 42) of the HCs were female, 17.6% (n = 9) were male. The number of  the patients without RLS was 41 (Group I), and the number of the patients with RLS was 17 (Group II). When basal ganglia structures were compared between groups of the patients with and without RLS, the fractional anisotropy (FA) value of the left putamen differed (Group I: 0.30 ± 0.06 vs. Group II: 0.25 ± 0.7, p = 0.01). The significant relationship was found attack frequency and presence of RLS with left putamen FA values according to multiple regression analysis. It was determined in this study that the changes in the microstructure of putamen, one of the basal ganglia structures, may be associated with the presence of RLS in migraineurs.

Prevalence of restless legs syndrome in people with diabetes mellitus: A pooling analysis of observational studies

BACKGROUND

Diabetes mellitus (DM) is associated with different clinical complications. The aim of this study was to explore the prevalence of RLS in people with diabetes mellitus and compare the risk of restless leg syndrome (RLS) between diabetic and non-diabetic population.

METHODS

We searched for studies of RLS prevalence in DM through PubMed, Embase, and Web of Science. Two authors independently completed the literature screening, data extraction, and bias risk assessment of eligible studies. All observational studies that assessed the prevalence or risk of RLS in DM were included, where the diagnosis of RLS was based on the International Restless Legs Syndrome Study Group (IRLSSG). Percentages, odds ratio (OR) with 95% confidence intervals (CI) were used to assess pooled estimates of RLS prevalence and risk based on random-effects models. Newcastle-Ottawa-scale (NOS) or a modified NOS were used to evaluate the quality of studies.

FINDINGS

A total of 42 studies, including 835,986 participants, met the eligibility criteria for the meta-analysis. Among them, 30 studies were included in meta-analysis to analyze the prevalence of RLS. A second meta-analysis was conducted using 31 studies to determine RLS risk between diabetes and non-diabetes. The results indicate that between 25% (95% confidence interval 21%-29%) of people with diabetes showed signs of RLS, and people with diabetes had an increased risk of developing RLS compare to people without diabetes (OR 1.98, 95%CI 1.66- 2.34, p < 0.001). However, the available evidence was limited due to potential risk of bias and variability between studies (I² >75%), all of observational design.

INTERPRETATION

Our study suggests that the prevalence and risk of RLS might be higher in DM patients than in non-diabetes population. However, given limitations in the analysis and study design, the findings need to be corroborated in future studies.

FUNDING

This work was supported by the Basic Conditions Platform Construction Project of Sichuan Science and Technology Department (2019JDPT0015), and the "1・3・5 project for disciplines of excellence, West China Hospital, Sichuan University" (ZYJC18003).

Migraine and Medical Ramifications: A Comprehensive Overview Based on Observational Study Meta-Analyses

Purpose: An umbrella review was conducted for comprehensively evaluating previous review-based literature together with meta-analysis of observational investigations probing correlations between migraine and medical end-point ramifications in patients. The breadth and validity of these associations were assessed.

Methods: Multiple online scientific repositories (including PubMed, Medline, Embase, and Web of Science) were investigated (inception-August 2021) for related meta-analyses focusing on links between migraine and all possible health/medical ramification end-points. A summary effect size and 95% CIs were determined for each identified study with such links. Heterogeneity and small-study influence traces were also evaluated. The AMSTAR 2 platform was employed for evaluating standards of methodology, together with objective criteria, for assessing the standards of datasets from each medical end-point scrutinized in this study.

Results: A total of 25 scientific reports comprising 10,237,230 participants for 49 meta-analyses of observational studies were selected. Among such 49 outcomes, 30 demonstrated statistical significance (P < 0.05). Significant associations were observed in multiple diseases, including cardiovascular/cerebrovascular, cerebral, pregnancy-related and metabolic disorders, other outcomes, and mortality.

Conclusion: The results showed that migraine increased the risk of 29 health outcomes, though lowered the risk of breast cancer. However, evidence quality was graded as high only for angina. The evidence quality of ischaemic stroke, stroke, MACCE, WMAs, and asthma was graded as moderate. All remaining 24 outcomes had an evidence grade of “weak.”

Comorbidities of primary headache disorders: a literature review with meta-analysis

Background

Primary headache disorders are common and burdensome conditions. They are associated to several comorbidities, such as cardiovascular or psychiatric ones, which, in turn, contribute to the global burden of headache. The aim of this study is to provide a comprehensive description of the pooled prevalence of comorbidities of primary headache disorders using a meta-analytical approach based on studies published between 2000 and 2020.

Methods

Scopus was searched for primary research (clinical and population studies) in which medical comorbidities were described in adults with primary headache disorders. Comorbidities were extracted using a taxonomy derived from the Global Burden of Disease (GBD) study. We compared prevalence of comorbidities among headache sufferers against general population using GBD-2019 estimates, and compared comorbidities’ proportions in clinical vs. population studies, and by age and gender.

Results

A total of 139 studies reporting information on 4.19 million subjects with primary headaches were included: in total 2.75 million comorbidities were reported (median per subject 0.64, interquartile range 0.32–1.07). The most frequently addressed comorbidities were: depressive disorders, addressed in 51 studies (pooled proportion 23 %, 95 % CI 20–26 %); hypertension, addressed in 48 studies (pooled proportion 24 %, 95 % CI 22–26 %); anxiety disorders addressed in 40 studies (pooled proportion 25 %, 95 % CI 22–28 %). For conditions such as anxiety, depression and back pain, prevalence among headache sufferers was higher than in GBD-2109 estimates. Associations with average age and female prevalence within studies showed that hypertension was more frequent in studies with higher age and less females, whereas fibromyalgia, restless leg syndrome, and depressive disorders were more frequent in studies with younger age and more female.

Conclusions

Some of the most relevant comorbidities of primary headache disorders – back pain, anxiety and depression, diabetes, ischemic heart disease and stroke – are among the most burdensome conditions, together with headache themselves, according to the GBD study. A joint treatment of headaches and of these comorbidities may positively impact on headache sufferers’ health status and contribute to reduce the impact of a group of highly burdensome diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-021-01281-z.

Lasmiditan in patients with common migraine comorbidities: a post hoc efficacy and safety analysis of two phase 3 randomized clinical trials

OBJECTIVE

Determine whether common migraine comorbidities affect the efficacy and safety of lasmiditan, a 5-HT_1F receptor agonist approved in the United States for the acute treatment of migraine.

METHODS

In SPARTAN and SAMURAI (double-blind Phase 3 clinical trials), patients with migraine were randomized to oral lasmiditan 50 mg (SPARTAN only), 100mg, 200 mg, or placebo. Lasmiditan increased the proportion of pain-free and most bothersome symptom (MBS)-free patients at 2 h after dose compared with placebo. Most common treatment-emergent adverse events (TEAEs) were dizziness, paraesthesia, somnolence, fatigue, nausea, muscular weakness, and hypoesthesia. Based upon literature review of common migraine comorbidities, Anxiety, Allergy, Bronchial, Cardiac, Depression, Fatigue, Gastrointestinal, Hormonal, Musculoskeletal/Pain, Neurological, Obesity, Sleep, and Vascular Comorbidity Groups were created. Using pooled results, efficacy and TEAEs were assessed to compare patients with or without a given common migraine comorbidity. To compare treatment groups, p-values were calculated for treatment-by-subgroup interaction, based on logistic regression with treatment-by-comorbidity condition status (Yes/No) as the interaction term; study, treatment group, and comorbidity condition status (Yes/No) were covariates. Differential treatment effect based upon comorbidity status was also examined. Trial registration at clinicaltrials.gov: SAMURAI (NCT02439320) and SPARTAN (NCT02605174).

RESULTS

Across all the Comorbidity Groups, with the potential exception of fatigue, treatment-by-subgroup interaction analyses did not provide evidence of a lasmiditan-driven lasmiditan versus placebo differential treatment effect dependent on Yes versus No comorbidity subgroup for either efficacy or TEAE assessments.

CONCLUSIONS

The efficacy and safety of lasmiditan for treatment of individual migraine attacks appear to be independent of comorbid conditions.

Dopa responsive headache: Restless head syndrome or a cephalic variant of restless legs syndrome?

Restless legs syndrome (RLS) is a common but highly undiagnosed sensorimotor disorder. It typically affects the lower extremities. However, various other parts of the body can be involved, such as the arms, the abdomen, the face, the oral cavity, head-neck, and the genital area. In addition, RLS is linked with a large number of comorbid conditions, including various headache disorders. Herein we are reporting two cases of RLS who also had headaches. The headaches fulfilled the criteria of chronic tension-type headache (CTTH). The administration of levodopa provided improvement in both RLS and CTTH. We suggest that that headache in a subset of patients with RLS may be the part of RLS symptoms complex.

Migraine and Sleep in Children: A Bidirectional Relationship

Migraine and sleep disorders in children exhibit a bidirectional relationship. This relationship is based on shared pathophysiology. Migraine involves activation of the trigeminal vascular system. Nociceptive neurons that innervate the dura release various vasoactive peptides. Calcitonin gene-related peptide is the most active of these peptides. Neural pathways that are involved in sleep generation are divided into those responsible for circadian rhythm, wake promotion, non-rapid eye movement, and rapid eye movement sleep activation. Sleep state switches are a critical component of these systems. The cerebral structures, networks, and neurochemical systems that are involved in migraine align closely with those responsible for the regulation of sleep. Neurochemical systems that are involved with both the pathogenesis of migraine and regulation of sleep include adenosine, melatonin, orexin, and calcitonin gene-related peptide. Sleep disorders represent the most common comorbidity with migraine in childhood. The prevalence of parasomnias, obstructive sleep apnea, and sleep-related movement disorders is significantly greater in children migraineurs. Infantile colic is a precursor of childhood migraine. Treatment of comorbid sleep disorders is important for the appropriate management of children with migraine. Sleep-based behavioral interventions can be of substantial benefit. These interventions are particularly important in children due to limited evidence for effective migraine pharmacotherapy.

Integrating Pathophysiology in Migraine: Role of the Gut Microbiome and Melatonin

BACKGROUND

The pathoetiology and pathophysiology of migraine are widely accepted as unknown.

METHODS

The current article reviews the wide array of data associated with the biological underpinnings of migraine and provides a framework that integrates previously disparate bodies of data.

RESULTS

The importance of alterations in stress- and pro-inflammatory cytokine- induced gut dysbiosis, especially butyrate production, are highlighted. This is linked to a decrease in the availability of melatonin, and a relative increase in the N-acetylserotonin/melatonin ratio, which has consequences for the heightened glutamatergic excitatory transmission in migraine. It is proposed that suboptimal mitochondria functioning and metabolic regulation drive alterations in astrocytes and satellite glial cells that underpin the vasoregulatory and nociceptive changes in migraine.

CONCLUSION

This provides a framework not only for classical migraine associated factors, such as calcitonin-gene related peptide and serotonin, but also for wider factors in the developmental pathoetiology of migraine. A number of future research and treatment implications arise, including the clinical utilization of sodium butyrate and melatonin in the management of migraine.

Why Are Women Prone to Restless Legs Syndrome?

Restless legs syndrome is a relatively common neurologic disorder considerably more prevalent in women than in men. It is characterized by an inactivity-induced, mostly nocturnal, uncomfortable sensation in the legs and an urge to move them to make the disagreeable sensation disappear. Some known genes contribute to this disorder and the same genes contribute to an overlapping condition—periodic leg movements that occur during sleep and result in insomnia. Dopamine and glutamate transmission in the central nervous system are involved in the pathophysiology, and an iron deficiency has been shown in region-specific areas of the brain. A review of the literature shows that pregnant women are at particular risk and that increased parity is a predisposing factor. Paradoxically, menopause increases the prevalence and severity of symptoms. This implies a complex role for reproductive hormones. It suggests that changes rather than absolute levels of estrogen may be responsible for the initiation of symptoms. Both iron (at relatively low levels in women) and estrogen (at relatively high oscillating levels in women) influence dopamine and glutamate transmission, which may help to explain women’s vulnerability to this condition. The syndrome is comorbid with several disorders (such as migraine, depression, and anxiety) to which women are particularly prone. This implies that the comorbid condition or its treatment, or both, contribute to the much higher prevalence in women than in men of restless legs syndrome.

Can we now say that commonalities between restless leg syndrome and migraine exist?

The recent manuscript by Xinglong Yang and colleagues provided the first relatively reliable estimate of restless leg syndrome (RLS) prevalence among migraine sufferers, which was estimated at 19% (95% CI 14-24%). The implications of the association between the two conditions are wide, and call for further action aimed to address common disease mechanism-associated conditions such as sleep-related ones and associated burden.