Development and Validation of Machine Learning Models to Predict Postoperative Delirium Using Clinical Features and Polysomnography Variables.

Background: Delirium affects up to 50% of patients following high-risk surgeries and is associated with poor long-term prognosis. This study employed machine learning to predict delirium using polysomnography (PSG) and sleep-disorder questionnaire data, and aimed to identify key sleep-related factors for improved interventions and patient outcomes. Methods: We studied 912 adults who underwent surgery under general anesthesia at a tertiary hospital (2013-2024) and had PSG within 5 years of surgery. Delirium was assessed via clinical diagnoses, antipsychotic prescriptions, and psychiatric consultations within 14 days postoperatively. Sleep-related data were collected using PSG and questionnaires. Machine learning predictions were performed to identify postoperative delirium, focusing on model accuracy and feature importance. Results: This study divided the 912 patients into an internal training set (700) and an external test set (212). Univariate analysis identified significant delirium risk factors: midazolam use, prolonged surgery duration, and hypoalbuminemia. Sleep-related variables such as fewer rapid eye movement (REM) episodes and higher daytime sleepiness were also linked to delirium. An extreme gradient-boosting-based classification task achieved an AUC of 0.81 with clinical variables, 0.60 with PSG data alone, and 0.84 with both, demonstrating the added value of PSG data. Analysis of Shapley additive explanations values highlighted important predictors: surgery duration, age, midazolam use, PSG-derived oxygen saturation nadir, periodic limb movement index, and REM episodes, demonstrating the relationship between sleep patterns and the risk of delirium. Conclusions: The artificial intelligence model integrates clinical and sleep variables and reliably identifies postoperative delirium, demonstrating that sleep-related factors contribute to its identification. Predicting patients at high risk of developing postoperative delirium and closely monitoring them could reduce the costs and complications associated with delirium.

Clinical profile and treatment outcomes of idiopathic intracranial hypertension: a multicenter study from Korea.

BACKGROUND: Currently, there is a relative lack of detailed reports regarding clinical presentation and outcome of idiopathic intracranial hypertension in Asians. This study aims to describe the clinical features and treatment outcomes of Korean patients with idiopathic intracranial hypertension. METHODS: We prospectively recruited patients with idiopathic intracranial hypertension from one hospital and retrospectively analyzed the medical records of 11 hospitals in Korea. We collected data regarding preceding medical conditions or suspected medication exposure, headache phenotypes, other associated symptoms, detailed neuroimaging findings, treatments, and outcomes after 1-2 and 3-6 months of treatment. RESULTS: Fifty-nine (83.1% women) patients were included. The mean body mass index was 29.11 (standard deviation, 5.87) kg/m2; only 27 patients (45.8%) had a body mass index of ≥ 30 kg/m2. Fifty-one (86.4%) patients experienced headaches, patterns of which included chronic migraine (15/51 [29.4%]), episodic migraine (8/51 [15.7%]), probable migraine (4/51 [7.8%]), chronic tension-type headache (3/51 [5.9%]), episodic tension-type headache (2/51 [3.9%]), probable tension-type headache (2/51 [3.9%]), and unclassified (17/51 [33.3%]). Medication overuse headache was diagnosed in 4/51 (7.8%) patients. After 3-6 months of treatment, the intracranial pressure normalized in 8/32 (25.0%), improved in 17/32 (53.1%), no changed in 7/32 (21.9%), and worsened in none. Over the same period, headaches remitted or significantly improved by more than 50% in 24/39 patients (61.5%), improved less than 50% in 9/39 (23.1%), and persisted or worsened in 6/39 (15.4%) patients. CONCLUSION: Our findings suggest that the features of Asian patients with idiopathic intracranial hypertension may be atypical (i.e., less likely obese, less female predominance). A wide spectrum of headache phenotypes was observed. Medical treatment resulted in overall favorable short-term outcomes; however, the headaches did not improve in a small proportion of patients.

Headache in Brain Tumors.

The prevalence of brain tumors in patients with headache is very low; however, 48% to 71% of patients with brain tumors experience headache. The clinical presentation of headache in brain tumors varies according to age; intracranial pressure; tumor location, type, and progression; headache history; and treatment. Brain tumor-associated headaches can be caused by local and distant traction on pain-sensitive cranial structures, mass effect caused by the enlarging tumor and cerebral edema, infarction, hemorrhage, hydrocephalus, and tumor secretion. This article reviews the current findings related to epidemiologic details, clinical manifestations, mechanisms, diagnostic approaches, and management of headache in association with brain tumors.

Coffee consumption and migraine: a population-based study.

Although coffee is one of the most consumed caffeinated beverages worldwide, the role of coffee consumption in migraine is controversial. This study examined the relationship between coffee consumption and clinical characteristics in participants with migraine compared to those with non-migraine headache. This cross-sectional study used data from a nationwide survey on headache and sleep. Coffee consumption was classified as no-to-low (< 1 cup/day), moderate (1-2 cups/day), or high (≥ 3 cups/day). Of the 3030 survey participants, 170 (5.6%) and 1,768 (58.3%) were identified as having migraine and non-migraine headache, respectively. Coffee consumption tended to increase in the order of non-headache, non-migraine headache, and migraine (linear-by-linear association, p = 0.011). Although psychiatric comorbidities (depression for migraine and anxiety for non-migraine headache) and stress significantly differed according to coffee consumption, most headache characteristics and accompanying symptoms did not differ among the three groups for participants with migraine and non-migraine headache. Response to acute headache treatment-adjusted for age, sex, depression, anxiety, stress, preventive medication use, and current smoking-was not significantly different by coffee consumption in participants with migraine and non-migraine headache. In conclusion, most headache-related characteristics and acute treatment response did not significantly differ by coffee consumption in migraine and non-migraine headache.

Shared comorbidity of depression, migraine, insomnia, and fibromyalgia in a population-based sample.

BACKGROUND: Depression, migraine, insomnia, and fibromyalgia are reportedly comorbidities. Nevertheless, no study has evaluated the comorbidity of all four of these disorders. This study aimed to investigate the comorbidity of these four disorders. METHODS: Cross-sectional analyses were performed using data of the Circannual Change in Headache and Sleep study, an online nationwide population-based survey. Validated questionnaires were used to diagnose the disorders and measure quality of life. The change of clinical characteristics by addition of any comorbidity was analyzed using the Jonckheere-Terpstra trend test. RESULTS: The prevalence rates of depression, migraine, insomnia, and fibromyalgia were 7.2 %, 5.6 %, 13.3 %, and 5.8 %, respectively. Among the 3030 included participants, 494 (16.3 %), 164 (5.4 %), 40 (1.3 %), and 6 (0.2 %) had one, two, three, and four of these conditions, respectively. The number of headache days per 30 days (Jonckheere-Terpstra trend test, p = 0.011) and migraine-related disability (migraine disability assessment score, p = 0.021) increased with an increase in the number of comorbidities but not with the intensity of headache (visual analog scale, p = 0.225) among participants with migraine. The severity of insomnia (Insomnia Severity Index, p < 0.001) and fibromyalgia (fibromyalgia severity score, p = 0.002) increased with additional comorbidities; however, depression (Patient Health Questionnaire-9, p = 0.384) did not show such an increase. LIMITATIONS: The diagnoses of conditions were based on self-reported questionnaires. CONCLUSIONS: The findings confirmed significant comorbidity between depression, migraine, insomnia, and fibromyalgia. Health professionals should be aware of the probable comorbidity of depression, migraine, insomnia, and fibromyalgia when caring for individuals with any of these four disorders.

An Analysis of the Determinants of the Health-Related Quality of Life in Asian Patients With Cluster Headaches During Cluster Periods Using the Time Trade-Off Method.

BACKGROUND AND PURPOSE: Patients with cluster headache (CH) exhibit impaired health-related quality of life (HRQoL). However, there have been few studies related to the HRQoL of patients with CH from Asian backgrounds. This study aimed to determine the impact of CH on HRQoL and to identify the factors affecting HRQoL in patients with CH during cluster periods. METHODS: This prospective study enrolled patients with CH from 17 headache clinics in South Korea between September 2016 and February 2021. The study aimed to determine HRQoL in patients with CH using the EuroQol 5 Dimensions (EQ-5D) index and the time trade-off (TTO) method. Age- and sex-matched headache-free participants were recruited as a control group. RESULTS: The study included 423 patients with CH who experienced a cluster period at the time. EQ-5D scores were lower in patients with CH (0.88±0.43, mean±standard deviation) than in the controls (0.99±0.33, p<0.001). The TTO method indicated that 58 (13.6%) patients with CH exhibited moderate-to-severe HRQoL deterioration. The HRQoL states in patients with CH were associated with current smoking patterns, headache severity, frequency, and duration, and scores on the Generalized Anxiety Disorder 7-item scale (GAD-7), Patient Health Questionnaire 9-item scale (PHQ-9), 6-item Headache Impact Test, and 12-item Allodynia Symptom Checklist. Multivariable logistic regression analyses demonstrated that the HRQoL states in patients with CH were negatively correlated with the daily frequency of headaches, cluster period duration, and GAD-7 and PHQ-9 scores. CONCLUSIONS: Patients with CH experienced a worse quality of life during cluster periods compared with the headache-free controls, but the degree of HRQoL deterioration varied among them. The daily frequency of headaches, cluster period duration, anxiety, and depression were factors associated with HRQoL deterioration severity in patients with CH.

Identification of dendritic cell precursor from the CD11c+ cells expressing high levels of MHC class II molecules in the culture of bone marrow with FLT3 ligand.

Dendritic cells (DCs) are readily generated from the culture of mouse bone marrow (BM) treated with either granulocyte macrophage-colony stimulating factor (GM-CSF) or FMS-like tyrosine kinase 3 ligand (FLT3L). CD11c+MHCII+ or CD11c+MHCIIhi cells are routinely isolated from those BM cultures and generally used as in vitro-generated DCs for a variety of experiments and therapies. Here, we examined CD11c+ cells in the BM culture with GM-CSF or FLT3L by staining with a monoclonal antibody 2A1 that is known to recognize mature or activated DCs. Most of the cells within the CD11c+MHCIIhi DC gate were 2A1+ in the BM culture with GM-CSF (GM-BM culture). In the BM culture with FLT3L (FL-BM culture), almost of all the CD11c+MHCIIhi cells were within the classical DC2 (cDC2) gate. The analysis of FL-BM culture revealed that a majority of cDC2-gated CD11c+MHCIIhi cells exhibited a 2A1-CD83-CD115+CX3CR1+ phenotype, and the others consisted of 2A1+CD83+CD115-CX3CR1- and 2A1-CD83-CD115-CX3CR1- cells. According to the antigen uptake and presentation, morphologies, and gene expression profiles, 2A1-CD83-CD115-CX3CR1- cells were immature cDC2s and 2A1+CD83+CD115-CX3CR1- cells were mature cDC2s. Unexpectedly, however, 2A1-CD83-CD115+CX3CR1+ cells, the most abundant cDC2-gated MHCIIhi cell subset in FL-BM culture, were non-DCs. Adoptive cell transfer experiments in the FL-BM culture confirmed that the cDC2-gated MHCIIhi non-DCs were precursors to cDC2s, i.e., MHCIIhi pre-cDC2s. MHCIIhi pre-cDC2s also expressed the higher level of DC-specific transcription factor Zbtb46 as similarly as immature cDC2s. Besides, MHCIIhi pre-cDC2s were generated only from pre-cDCs and common DC progenitor (CDP) cells but not from monocytes and common monocyte progenitor (cMoP) cells, verifying that MHCIIhi pre-cDC2s are close lineage to cDCs. All in all, our study identified and characterized a new cDC precursor, exhibiting a CD11c+MHCIIhiCD115+CX3CR1+ phenotype, in FL-BM culture.

Headache in Pediatric Moyamoya Disease after Revascularization Surgery.

INTRODUCTION: Patients with moyamoya disease (MMD) often have headaches after successful revascularization surgery. We aimed to characterize headache in surgically treated MMD patients and elucidate its clinical meaning and pathophysiology. METHODS: Headache and related symptoms were surveyed using structured questionnaires in pediatric MMD patients with follow-up for 6 months or longer after indirect revascularization surgery. Clinical information including initial presentation, surgical method, and outcome was collected from medical records. Surgical outcomes were assessed clinically and by perfusion imaging. We defined "headache associated with MMD" as the headache accompanied by a transient ischemic attack or provoked by hyperventilation. Other headaches were further classified based on the diagnostic criteria of the International Headache Society-3. We analyzed the characteristics of "headache associated with MMD" and newly developed headache after surgery. RESULTS: Among 90 participants, 65 (72.2%) had headaches within the last year before survey, including 28 (43.1%) with "headaches associated with MMD," 10 (15.3%) with probable migraines, 2 (3.1%) with infrequent episodic tension-type headaches, and 4 (6.2%) with probable tension-type headaches. Headache quality was pulsatile in 27 (41.5%) patients and pressing or tightening in 27 (41.5%) patients. Nausea or vomiting was accompanied in 30 (46.2%) patients. Headache upon awakening was reported in 37 (57.8%) patients. Headache disturbed daily life in 12 (18.5%) patients. Among the 32 (35.6%) patients who suffered headache during both the pre- and postoperative period, the headache quality was similar in 27 (84.4%) patients, and its severity decreased in 24 (75.0%) and did not change in 8 (25.0%) patients. Twelve (13.3%) patients experienced newly developed headaches after surgery. Among them, six (50.0%) were classified as having "headaches associated with MMD." They were predominantly electric shock-like or stabbing in 5 (45.6%) patients and nondisturbing in all patients. All 90 patients achieved improvement of ischemic symptoms after surgery. CONCLUSION: Headaches often persist or newly develop after revascularization surgery in MMD patients. Accompanying nausea or vomiting and occurrence upon awakening are characteristic features. Postoperative headache does not necessarily imply insufficient disease control.

No change in interictal C-reactive protein levels in individuals with episodic and chronic migraine: A case-control study and literature review.

Objectives: The levels of some migraine biomarkers differ between episodic migraine (EM) and chronic migraine (CM), but information on C-reactive protein (CRP) levels in EM and CM is conflicting. Thus, this study aimed to evaluate CRP levels in participants with EM and CM in comparison to those in healthy controls. Methods: Plasma CRP levels were evaluated by high-sensitivity CRP tests in female participants with EM (n = 174) and CM (n = 191) and healthy controls (n = 50). Results: The results showed no significant difference in CRP levels among the EM, CM, and control groups (median and interquartile range, 0.40 [0.15-0.70] mg/L vs. 0.40 [0.15-1.00] mg/L vs. 0.15 [0.15-0.90] mg/L, p = 0.991). The ratio of individuals with elevated CRP levels (>3.0 mg/L) did not significantly differ among the EM, CM, and control groups (3.4% [6/174] vs. 2.1% [4/191] vs. 0.0% [0/50], p = 0.876). Multivariable regression analyses revealed that CRP levels were not significantly associated with headache frequency per month (ß = -0.076, p = 0.238), the severity of anxiety (Generalized Anxiety Disorder-7 score, ß = 0.143, p = 0.886), and depression (Patient Health Questionnaire-9 score, ß = 0.143, p = 0.886). Further, CRP levels did not significantly differ according to clinical characteristics, fibromyalgia, medication overuse, preventive treatment, and classes of preventive treatment medications. Among participants with a body mass index ≥25 kg/m2, the CRP levels in EM (n = 41) and CM (n = 17) were numerically higher than those in the control (n = 6) (1.30 [0.28-4.25] mg/L vs. 1.10 [0.50-3.15] mg/L vs. 0.40 [0.15-0.83] mg/L, p = 0.249) but did not reach statistical significance. Conclusions: The interictal CRP level is not likely to be a biomarker for EM or CM.

Association Between Nap and Reported Cognitive Function and Role of Sleep Debt: A Population-Based Study.

BACKGROUND AND PURPOSE: The relationship between napping and cognition remains controversial. This study aimed to investigate the association between napping and cognition according to sleep debt in the Korean adult population. METHODS: A population-based nationwide cross-sectional survey was conducted in 2018. A two-stage stratified random sample of Koreans aged ≥19 years was selected and evaluated using questionnaires by trained interviewers. Cognitive function was assessed using the Mail-In Cognitive Function Screening Instrument (MCFSI). Sleep habits on weekdays and weekends, napping, and subjective sleep requirements were assessed using the questionnaires. Accumulated sleep debt was calculated by subtracting the weekly average sleep duration from subjective sleep requirements. Sleep quality, daytime sleepiness, insomnia, depression, demographics, and comorbidities were assessed. Participants were grouped into those with sleep debt ≤60 min and those with sleep debt >60 min. Multiple linear regression was used to estimate the independent association between the factors and cognition. RESULTS: In total, 2,501 participants were included in the analysis. Naps were reported in 726 (29.0%) participants (nappers). The mean MCFSI score was higher in nappers (3.4±3.6) than in non-nappers (2.3±3.0) (p<0.001). Multiple linear regression controlling for age, alcohol, smoking, depression, insomnia, daytime sleepiness, sleep quality, and education revealed that 30 to 60 min of napping was associated with worse cognitive function in participants with sleep debts ≤60 min, while >60 min of napping was associated with better cognitive function in participants with sleep debts >60 min. CONCLUSIONS: In general, naps are associated with worse cognitive function in the Korean adult population. However, for those with sleep debt of >60 min, naps for >60 min were associated with better cognitive function.

Interictal plasma endothelin-1 levels do not change in individuals with episodic and chronic migraine.

BACKGROUND: Individuals with migraine present ictal elevation of endothelin-1 levels. Migraine can be subclassified into episodic migraine and chronic migraine. Apart from the inconsistent reports on interictal endothelin-1 levels, most studies did not distinguish between episodic migraine and chronic migraine. METHODS: We measured plasma endothelin-1 levels in participants with episodic migraine (n = 87), with chronic migraine (n = 88), and controls (n = 50). RESULTS: Interictal endothelin-1 levels were not significantly different among participants with episodic migraine, those with chronic migraine, and controls (pg/ml, median and interquartile range, 10.19 [7.76-13.69] vs. 9.25 [6.91-10.73] vs. 9.46 [7.00-14.19], p = 0.131). After excluding participants with fibromyalgia (n = 50) and medication-overuse headache (n = 21), endothelin-1 levels were still similar among groups (10.51 [7.96-14.10] vs. 9.24 [6.96-10.81] vs. 9.46 [7.00-14.19], p = 0.230). Endothelin-1 levels did not significantly differ among participants with migraine with aura, those with migraine without aura, and controls (9.36 [4.26-13.35] vs. 9.50 [7.23-13.02] vs. 9.46 [7.00-14.19], p = 0.975). There was no significant association of endothelin-1 with headache intensity (mild, 8.99 [8.99-8.99] vs. moderate, 8.71 [6.85-12.15] vs. severe, 9.55 [7.23-13.13], p = 0.517) or headache frequency per month (exponential and 95% confidence interval, 0.709 [0.296-1.698], p = 0.440) in participants with episodic migraine and chronic migraine. CONCLUSIONS: Interictal plasma endothelin-1 level is an unlikely marker for episodic migraine and chronic migraine.

Validity and reliability of the self-administered Visual Aura Rating Scale questionnaire for migraine with aura diagnosis: A prospective clinic-based study.

OBJECTIVE: To assess the validity and reliability of the self-administered Visual Aura Rating Scale (VARS) questionnaire using a hospital-based sample in a cross-sectional setting. BACKGROUND: Visual aura is the most common type of aura manifesting in 98%-99% of migraine with aura (MA). The VARS is a diagnostic rating scale used to quantify the cardinal characteristics of MA and has shown high sensitivity and specificity in the diagnosis of visual aura. METHODS: We translated the VARS into Korean and constructed a five-item self-administered questionnaire based on the VARS. We consecutively recruited first-visit patients with migraine at the neurology clinics of two university hospitals. The scoring of the self-administered VARS questionnaire was the same as that for the original VARS. We assessed criterion validity and internal consistency reliability. The diagnosis of migraine and aura was assigned by two headache neurologists based on a comprehensive clinical assessment using the International Classification of Headache Disorders, 3rd edition. RESULTS: A total of 240 participants with migraine were enrolled. Of these, 55 (22.9%) had MA. All participants with MA had visual aura. Receiver operating characteristic curve analysis revealed that a cutoff score of 3 provided the highest rate of correct identification of patients ([200/240], 83.3%), with a sensitivity of 96.4% (95% confidence interval [CI], 84.5%-99.6%) and specificity of 79.5% (95% CI, 72.9%-85.0%). Cronbach's alpha coefficient was 0.852. CONCLUSION: The self-administered VARS questionnaire is a valid and reliable instrument for the screening of visual aura in patients with migraine in neurology outpatient clinics.

Smoking History and Clinical Features of Cluster Headache: Results from the Korean Cluster Headache Registry.

BACKGROUND AND PURPOSE: Epidemiologic data suggest that cluster headache (CH) is significantly associated with cigarette smoking. The aim of this study was to determine differences in features between patients with a smoking history and those who are never-smokers, using data from a prospective multicenter registry. METHODS: Data used in this study were obtained from the Korean Cluster Headache Registry that collected data from consecutive patients diagnosed with CH. We compared clinical and demographic features between ever-smokers (current or former smokers) and never-smokers. RESULTS: This study enrolled 250 patients who were diagnosed with CH, of which 152 (60.8%) were ever-smokers and 98 (39.2%) were never-smokers. The age at CH onset was significantly lower in the never-smoker group than in the ever-smoker group [27.1±12.9 years vs. 30.6±10.9 years (mean±standard deviation), p=0.024]. Seasonal rhythmicity (58.1% vs. 44.7%, p=0.038) and triptan responsiveness (100% vs. 85.1%, p=0.001) were higher in never-smokers, while other clinical features such as pain severity, duration, attack frequency, and associated autonomic symptoms did not differ significantly between the groups. The male-to-female ratio was markedly higher in ever-smokers (29.4:1) than in never-smokers (1.7:1). CONCLUSIONS: Most of the clinical features did not differ significantly between patients with a smoking history and never-smokers. However, the age at CH onset, sex ratio, and seasonal rhythmicity were significantly associated with smoking history.

Granulocyte Macrophage-Colony Stimulating Factor Produces a Splenic Subset of Monocyte-Derived Dendritic Cells That Efficiently Polarize T Helper Type 2 Cells in Response to Blood-Borne Antigen.

Dendritic cells (DCs) are key antigen-presenting cells that prime naive T cells and initiate adaptive immunity. Although the genetic deficiency and transgenic overexpression of granulocyte macrophage-colony stimulating factor (GM-CSF) signaling were reported to influence the homeostasis of DCs, the in vivo development of DC subsets following injection of GM-CSF has not been analyzed in detail. Among the treatment of mice with different hematopoietic cytokines, only GM-CSF generates a distinct subset of XCR1-33D1- DCs which make up the majority of DCs in the spleen after three daily injections. These GM-CSF-induced DCs (GMiDCs) are distinguished from classical DCs (cDCs) in the spleen by their expression of CD115 and CD301b and by their superior ability to present blood-borne antigen and thus to stimulate CD4+ T cells. Unlike cDCs in the spleen, GMiDCs are exceptionally effective to polarize and expand T helper type 2 (Th2) cells and able to induce allergic sensitization in response to blood-borne antigen. Single-cell RNA sequencing analysis and adoptive cell transfer assay reveal the sequential differentiation of classical monocytes into pre-GMiDCs and GMiDCs. Interestingly, mixed bone marrow chimeric mice of Csf2rb+/+ and Csf2rb-/- demonstrate that the generation of GMiDCs necessitates the cis expression of GM-CSF receptor. Besides the spleen, GMiDCs are generated in the CCR7-independent resident DCs of the LNs and in some peripheral tissues with GM-CSF treatment. Also, small but significant numbers of GMiDCs are generated in the spleen and other tissues during chronic allergic inflammation. Collectively, our present study identifies a splenic subset of CD115hiCD301b+ GMiDCs that possess a strong capacity to promote Th2 polarization and allergic sensitization against blood-borne antigen.

Clinical features of chronic cluster headache based on the third edition of the International Classification of Headache Disorders: A prospective multicentre study.

The criterion for the remission period of chronic cluster headache (CCH) was recently revised from < 1 month to < 3 months in the third edition of the International Classification of Headache Disorders (ICHD-3). However, information on the clinical features of CCH based on the ICHD-3 criteria is currently limited. The present study aimed to investigate the clinical features of CCH based on ICHD-3 using data from the Korean Cluster Headache Registry (KCHR). The KCHR is a multicentre prospective registry of patients with cluster headache (CH) from 15 hospitals. Among the 250 participants with CH, 12 and 176 participants were classified as having CCH and episodic cluster headache (ECH), respectively. Among 12 participants with CCH, 6 (50%) had remission periods of < 1 month, and the remaining 6 (50%) had a remission period of 1-3 months. Six participants had CCH from the time of onset of CH, and in the other 6 participants, CCH evolved from ECH. CCH subjects had later age of onset of CH, developed the condition after a longer interval after CH onset, and had more migraine and less nasal congestion and/or rhinorrhoea than ECH subjects. Clinical features of CCH with remission periods < 1 month were not significantly different from those of CCH with remission periods of 1-3 months, except for the total number of bouts. More current smoking and less diurnal rhythmicity were observed in participants with CCH evolved from ECH compared to those with ECH. In conclusion, the number of subjects with CCH doubled when the revised ICHD-3 criteria were used. Most of clinical characteristics of CCH did not differ when the previous and current version of ICHD was applied and compared. Some clinical features of CCH were different from those of ECH, and smoking may have a role in CH chronification.

Validity and Reliability of the Fibromyalgia Rapid Screening Tool Among Individuals with Chronic Daily Headache: A Clinic-Based Study.

BACKGROUND: Fibromyalgia is a common chronic pain disorder typically associated with headache disorders, particularly chronic daily headache. However, fibromyalgia is typically underdiagnosed and undertreated. The Fibromyalgia Rapid Screening Tool questionnaire is a brief, self-administered questionnaire composed of six "yes/no" questions for detecting fibromyalgia. The Fibromyalgia Rapid Screening Tool questionnaire has demonstrated high sensitivity and specificity among patients with chronic diffuse pain conditions. This study assessed the validity and reliability of the aforementioned questionnaire for detecting fibromyalgia among patients with chronic daily headache. METHODS: Consecutive first-visit headache patients with primary chronic daily headache (≥15 days/month for three or more months) at the outpatient clinics of four university hospitals were enrolled in this study from April 2015 to October 2015, and the validity and reliability of the Fibromyalgia Rapid Screening Tool questionnaire for determining fibromyalgia were evaluated. Fibromyalgia was diagnosed according to the American College of Rheumatology criteria of 2010. RESULTS: A total of 171 patients with primary chronic daily headache were recruited, and 100 (58.4%) were determined to have fibromyalgia. Receiver operating characteristic curve analysis revealed that a cutoff score of 5 (corresponding to the number of positive items) provided the highest rate of correct identification of patients (77.2%), with a sensitivity of 70.0% and specificity of 87.3%. The positive and negative predictive values were 88.6% and 67.4%, respectively. The Cronbach's alpha coefficient was 0.684. CONCLUSIONS: The Fibromyalgia Rapid Screening Tool is a valid and reliable instrument for identifying fibromyalgia among patients with chronic daily headache.

Salivary glutamate is elevated in individuals with chronic migraine.

Background Glutamate has been implicated in migraine pathogenesis, and is elevated in the plasma, cerebrospinal fluid, and saliva in migraineurs. However, no comparison of glutamate levels among chronic migraine, episodic migraine and controls has been reported. The aim is to compare salivary glutamate levels of individuals with chronic migraine with those of individuals with episodic migraine and healthy controls. Methods We investigated salivary glutamate level of 46 women with chronic migraine, 50 women with episodic migraine, and 19 healthy controls via enzyme linked immunosorbent assay. Results The salivary glutamate level of the chronic migraine group (median and interquartile range, 20.47 [15.27-30.15] pmol/mg total protein) was significantly higher than those of the episodic migraine (16.17 [12.81-20.15] pmol/mg total protein, p = 0.008) and control (12.18 [9.40-16.24] pmol/mg total protein, p = 0.001) groups. The salivary glutamate level of the episodic migraine group was marginally elevated from that of the control group (post hoc p = 0.016). Thresholds of 16.58 and 17.94 pmol/mg total protein optimize the sensitivity and specificity to differentiate chronic migraine participants from healthy controls and episodic migraine participants, respectively. Conclusions Salivary glutamate level was elevated in chronic migraine participants. These data suggest that salivary glutamate level could be an indicator of CM.

Fibromyalgia Among Patients With Chronic Migraine and Chronic Tension-Type Headache: A Multicenter Prospective Cross-Sectional Study.

OBJECTIVES: To investigate the frequency and impact of fibromyalgia among patients with chronic migraine (CM) and chronic tension-type headache (CTTH). BACKGROUND: Fibromyalgia (FM) is a common comorbidity in patients with chronic headaches. CM and CTTH are the two common types of chronic headaches. METHODS: We conducted a cross-sectional study in neurology outpatient clinics of four university hospitals and selected first-visit 136 patients with CM and 35 patients with CTTH. FM was assessed based on the 2010 American College of Rheumatology diagnostic criteria. RESULTS: The frequency of FM was significantly higher among patients with CM when compared to those with CTTH (91/136 [66.9%] vs 9/35 [25.7%], P < .001). Logistic regression analyses revealed an increased odds ratio (OR) for FM for patients with CM when compared to those with CTTH after adjustment for age, sex, anxiety, depression, and insomnia (OR = 3.6, 95% confidence interval = 1.1-11.4). Furthermore, CM patients with FM had higher scores in FM Impact Questionnaire compared to CTTH patients with FM (51.5 ± 16.3 vs 43.7 ± 18.7, P = .015). Comorbidity of FM was associated with increased frequency of photophobia, phonophobia, anxiety, depression, and insomnia among patients with CM. Such association was not noted among patients with CTTH. CONCLUSION: FM based on 2010 American College of Rheumatology diagnostic criteria was more prevalent among patients with CM than those with CTTH. Some clinical features and comorbidities of CM varied with the presence of FM.

Clinical Features of Cluster Headache Patients in Korea.

Cluster headache (CH) is a rare underdiagnosed primary headache disorder with very severe unilateral pain and autonomic symptoms. Clinical characteristics of Korean patients with CH have not yet been reported. We analyzed the clinical features of CH patients from 11 university hospitals in Korea. Among a total of 200 patients with CH, only 1 patient had chronic CH. The average age of CH patients was 38.1 ± 8.9 years (range 19-60 years) and the average age of onset was 30.7 ± 10.3 years (range 10-57 years). The male-to-female ratio was 7:1 (2.9:1 among teen-onset and 11.7:1 among twenties-onset). Pain was very severe at 9.3 ± 1.0 on the visual analogue scale. The average duration of each attack was 100.6 ± 55.6 minutes and a bout of CH lasted 6.5 ± 4.5 weeks. Autonomic symptoms were present in 93.5% and restlessness or agitation was present in 43.5% of patients. Patients suffered 3.0 ± 3.5 (range 1-25) bouts over 7.3 ± 6.7 (range 1-30) years. Diurnal periodicity and season propensity were present in 68.5% and 44.0% of patients, respectively. There were no sex differences in associated symptoms or diurnal and seasonal periodicity. Korean CH patients had a high male-to-female ratio, relatively short bout duration, and low proportion of chronic CH, unlike CH patients in Western countries.