Cerebral endothelial dysfunction in reversible cerebral vasoconstriction syndrome: a case-control study

Radiological Findings in Reversible Cerebral Vasoconstriction Syndrome: A Systematic Review of Literature

Reversible cerebral vasoconstriction syndrome (RCVS) poses a complex neurological challenge characterized by sudden, severe headaches and multifocal cerebral vasoconstriction. While our understanding of its clinical aspects and underlying mechanisms has advanced, the focus of investigation remains on radiological manifestations. This systematic review aims to comprehensively analyze the existing literature on radiological findings in RCVS, synthesizing evidence from diverse imaging modalities to enhance the understanding of imaging features associated with the syndrome. Accurate diagnosis based on radiological findings is pivotal for initiating appropriate management and preventing complications. Specific markers may facilitate the differentiation of RCVS from other conditions, thereby enhancing patient care. This review explores a wide range of radiological presentations, from vasoconstriction to infarctions and hemorrhages, thereby refining diagnostic criteria and guiding clinical practice. By consolidating current knowledge, the review sheds light on areas of consensus, controversies, and gaps, with the aim of serving as a comprehensive resource for evidence-based decision-making.

Concurrent spontaneous coronary dissection and reversible cerebral vasoconstriction syndrome during postnatal care

BACKGROUND

Pregnancy-associated spontaneous coronary artery dissection (SCAD) and reversible cerebral vasoconstriction syndrome (RCVS) are rare conditions that may occur during pregnancy and the postpartum period. The coexistence of both diseases may pose a risk to patients, potentially resulting in a variety of complications and clinical manifestations. This is considered the first case of a patient who successfully recovered from a critical condition in the postpartum period, with contemporaneous SCAD and RCVS.

CASE PRESENTATION

A 33-year-old female with no known medical history was referred to the emergency department after experiencing cardiac arrest, which occurred 1 week after giving birth to her third child. She complained of sudden anterior squeezing chest pain, accompanied by a headache, and eventually collapsed due to ventricular fibrillation with seizure. She was successfully resuscitated after receiving basic life support. She showed an alert mentality and did not experience any further seizure events or additional neurological symptoms. Although vital sign remained stable, the level of highly sensitive troponin I was significantly elevated. Electrocardiography revealed sinus rhythm with T-wave inversion at V1-4, while chest computed tomography (CT) demonstrated severe aspiration pneumonia. The patient was admitted to the intensive care unit due to a high requirement of O2 supply. A consultation with the neurologic department and a brain magnetic resonance angiography (MRA) were conducted for the thunderclap headache. The brain MRA demonstrated stenosis in the basilar artery, the right M2 segment, and bilateral A1 segments, along with sulcal hyperintensity on post-contrast fluid-attenuated inversion recovery (FLAIR) suggesting blood-brain barrier breakdown due to vasoconstriction. Formal echocardiography showed regional wall motion abnormality in the left anterior descending artery (LAD) territory. After the improvement of pneumonia, a coronary angiography was performed, revealing diffuse luminal narrowing from the mid to distal LAD due to a long segmental, extensive dissection. We decided to maintain the medical therapy. A follow-up coronary CT angiography performed 6 months later revealed complete remission of the dissected coronary vessel, and a brain MRA checked 3 months later showed resolved vasoconstriction of the relevant cerebral vessels.

CONCLUSIONS

The physicians must be aware of pregnancy-associated complications in certain patients. Clear diagnoses and proper treatments are required in pregnant patients who may be exposed to multiple acute conditions, in order to reduce complications and achieve favorable outcomes.

Association between impaired dynamic cerebral autoregulation and BBB disruption in reversible cerebral vasoconstriction syndrome

BACKGROUND

Half of the sufferers of reversible cerebral vasoconstriction syndrome (RCVS) exhibit imaging-proven blood-brain barrier disruption. The pathogenesis of blood-brain barrier disruption in RCVS remains unclear and mechanism-specific intervention is lacking. We speculated that cerebrovascular dysregulation might be associated with blood-brain barrier disruption in RCVS. Hence, we aimed to evaluate whether the dynamic cerebral autoregulation is altered in patients with RCVS and could be associated with blood-brain barrier disruption.

METHODS

A cross-sectional study was conducted from 2019 to 2021 at headache clinics of a national tertiary medical center. Dynamic cerebral autoregulation was evaluated in all participants. The capacity of the dynamic cerebral autoregulation to damp the systemic hemodynamic changes, i.e., phase shift and gain between the cerebral blood flow and blood pressure waveforms in the very-low- and low-frequency bands were calculated by transfer function analysis. The mean flow correlation index was also calculated. Patients with RCVS received 3-dimensional isotropic contrast-enhanced T2 fluid-attenuated inversion recovery imaging to visualize blood-brain barrier disruption.

RESULTS

Forty-five patients with RCVS (41.9 ± 9.8 years old, 29 females) and 45 matched healthy controls (41.4 ± 12.5 years old, 29 females) completed the study. Nineteen of the patients had blood-brain barrier disruption. Compared to healthy controls, patients with RCVS had poorer dynamic cerebral autoregulation, indicated by higher gain in very-low-frequency band (left: 1.6 ± 0.7, p = 0.001; right: 1.5 ± 0.7, p = 0.003; healthy controls: 1.1 ± 0.4) and higher mean flow correlation index (left: 0.39 ± 0.20, p = 0.040; right: 0.40 ± 0.18, p = 0.017; healthy controls: 0.31 ± 0.17). Moreover, patients with RCVS with blood-brain barrier disruption had worse dynamic cerebral autoregulation, as compared to those without blood-brain barrier disruption, by having less phase shift in very-low- and low-frequency bands, and higher mean flow correlation index.

CONCLUSIONS

Dysfunctional dynamic cerebral autoregulation was observed in patients with RCVS, particularly in those with blood-brain barrier disruption. These findings suggest that impaired cerebral autoregulation plays a pivotal role in RCVS pathophysiology and may be relevant to complications associated with blood-brain barrier disruption by impaired capacity of maintaining stable cerebral blood flow under fluctuating blood pressure.

Reversible cerebral Vasoconstriction syndrome intERnational CollaborativE (REVERCE) network: Study protocol and rationale of a multicentre research collaboration

INTRODUCTION

Reversible cerebral vasoconstriction syndrome (RCVS) is a rare, but increasingly recognised cerebrovascular condition with an estimated annual age-standardised incidence of approximately three cases per million. Knowledge about risk factors and triggering conditions and information about prognosis and optimal treatment in these patients are limited.

METHODS

The REversible cerebral Vasoconstriction syndrome intERnational CollaborativE (REVERCE) project aims to elucidate the epidemiological and clinical characteristics of RCVS by collecting individual patient data from four countries (France, Italy, Taiwan and South Korea) in the setting of a multicentric study. All patients with a diagnosis of definite RCVS will be included. Data on the distribution of risk factors and triggering conditions, imaging data, neurological complications, functional outcome, risk of recurrent vascular events and death and finally the use of specific treatments will be collected. Subgroup analyses will be made based on age, gender, aetiology, ethnicity and geographical region of residence.

ETHICS AND DISSEMINATION

Ethical approval for the REVERCE study will be obtained from national or local institutional review boards in the participating centres. When needed, a standardised data transfer agreement will be provided for participating centres. We plan dissemination of our results in peer-reviewed international scientific journals and through conference presentations. We expect that the results of this unique study will lead to better understanding of clinical and epidemiological characteristics of RCVS patients.

Headache Attributed to Reversible Cerebral Vasoconstriction Syndrome (RCVS)

Reversible cerebral vasoconstriction syndrome (RCVS) is a condition with variable outcomes presenting a new onset thunderclap headache accompanied by focal neurological symptoms or seizures. It can be idiopathic or arise secondarily to a variety of trigger factors. The condition is increasingly recognized in clinical practice, but many facets remain poorly understood. This article aims to clarify the headache characteristics in RCVS, the temporal association of angiographic findings, the potential association of the condition with SARS-CoV-2 infection, and the clinical presentation of RCVS in children and is based on a systematic PRISMA search for published analytical or large descriptive observational studies. Data from 60 studies that fulfilled specific criteria were reviewed. Most people with RCVS exhibit a typical thunderclap, explosive, or pulsatile/throbbing headache, or a similar acute and severe headache that takes longer than 1 min to peak. Atypical presentations or absence of headaches are also reported and may be an underrecognized phenotype. In many cases, headaches may persist after resolution of RCVS. Focal deficits or seizures are attributed to associated complications including transient ischemic attacks, posterior reversible encephalopathy syndrome, ischemic stroke, cerebral edema, and intracranial hemorrhage. The peak of vasoconstriction occurs usually within two weeks after clinical onset, possibly following a pattern of centripetal propagation, and tends to resolve completely within 3 months, well after symptoms have subsided. There are a few reports of RCVS occurring in relation to SARS-CoV-2 infection, but potential underlying pathophysiologic mechanisms and etiological associations have not been confirmed. RCVS occurs in children most often in the context of an underlying disease. Overall, the available data in the literature are scattered, and large-scale prospective studies and international collaborations are needed to further characterize the clinical presentation of RCVS.

Update on primary headache associated with sexual activity and primary thunderclap headache

BACKGROUND

This narrative review aims to provide an update on primary headache associated with sexual activity and primary thunderclap headache.

METHODS

We conducted a literature search on PubMed with the keywords "headache associated with sexual activity", "sexual headache", "orgasmic cephalalgia", and "coital cephalalgia" in addition to "thunderclap headache" to assess the appropriateness of all published articles in this review.

RESULTS

Primary headache associated with sexual activity is a "primary" headache precipitated by sexual activity, which occurs as sexual excitement increases (progressive at onset), or manifests as an abrupt and intense headache upon orgasm (thunderclap at onset) or combines these above two features. Primary headache associated with sexual activity is diagnosed after a thorough investigation, including appropriate neuroimaging studies, to exclude life-threatening secondary causes such as subarachnoid hemorrhage. According to the criteria of the third edition of the International Classification of Headache Disorders, primary thunderclap headache is also a diagnosis by exclusion. The pathophysiology of primary headache associated with sexual activity and primary thunderclap headache remains incompletely understood. Treatment may not be necessary for all patients since some patients with primary headache associated with sexual activity and primary thunderclap headache have a self-limiting course.

CONCLUSION

A comprehensive neuroimaging study is needed for distinguishing primary headache associated with sexual activity or primary thunderclap headache from secondary causes. Primary headache associated with sexual activity and primary thunderclap headache are self-limited diseases and the prognoses are good, but some patients with primary headache associated with sexual activity may have a prolonged course.

Reversible Cerebral Vasoconstriction Syndrome Associated with Vasospasm of the Colic Arteries and Possibly Coronary Vasospasm

BACKGROUND Reversible cerebral vasoconstriction syndrome (RCVS) is a disorder characterized by recurrent thunderclap headaches and reversible cerebral vasoconstriction. CASE REPORT Herein, we present the case of a man in his forties with a disease entity related to RCVS accompanied by vasospasm of the extracerebral blood vessels throughout the body. The patient presented to the Emergency Department with a severe headache and epigastric pain. Initially receiving a misdiagnosis of functional pain, he continued to experience severe recurrent headaches, most often after urinating or defecating and was referred to our department. Suspecting RCVS, we performed magnetic resonance angiography, which revealed beaded irregularity in the right anterior cerebral and V4 vertebral arteries. The patient also had epigastric pain that coincided with each headache. Electrocardiography revealed pronounced ST-segment elevation in leads I and aVL and inverted T wave in lead III, while abdominal computed tomography angiography showed narrowing of the colic arteries. We named this disease "reversible systemic vasoconstriction syndrome" (RSVS) as a potential suggested terminology for the future. CONCLUSIONS RSVS is a clinical syndrome characterized by thunderclap headaches and simultaneous unbearable pain in extracerebral organs. To the best of our knowledge, this is the first case report of RCVS with coronary and colic artery vasospasm. We need to take great care of patients with chest or abdominal pain accompanied by recurrent thunderclap headaches, since they can be misdiagnosed with functional or psychogenic disorders.

[Reversible cerebral vasoconstriction syndrome and ischemic stroke]

The article describes a 45-year-old female patient with recurrent transient ischemic attacks and ischemic stroke due to spontaneous spasm of the middle cerebral artery, the anterior cerebral artery and distal part of the internal cerebral artery on the left, verified by MR angiography and CT angiography. It is assumed that the spasm caused damage to the vascular wall, an increase in its permeability, the development of edema, inflammation and subsequent fibrosis, therefore a complete restoration of the arterial lumen did not occur.

Pathophysiology of reversible cerebral vasoconstriction syndrome

Reversible cerebral vasoconstriction syndrome (RCVS) is a complex neurovascular disorder being recognized during the past two decades. It is characterized by multiple abrupt severe headaches and widespread cerebral vasoconstrictions, with potential complications such as ischemic stroke, convexity subarachnoid hemorrhage, intracerebral hemorrhage and posterior reversible encephalopathy syndrome. The clinical features, imaging findings, and dynamic disease course have been delineated. However, the pathophysiology of RCVS remains elusive. Recent studies have had substantial progress in elucidating its pathogenesis. It is now believed that dysfunction of cerebral vascular tone and impairment of blood–brain barrier may play key roles in the pathophysiology of RCVS, which explains some of the clinical and radiological manifestations of RCVS. Some other potentially important elements include genetic predisposition, sympathetic overactivity, endothelial dysfunction, and oxidative stress, although the detailed molecular mechanisms are yet to be identified. In this review, we will summarize what have been revealed in the literature and elaborate how these factors could contribute to the pathophysiology of RCVS.

A Case Report of Reversible Cerebral Vasoconstriction Syndrome in a Patient With Systemic Scleroderma

Reversible cerebral vasoconstriction syndrome (RCVS) is represented by recurrent severe thunderclap headache, with or without neurological symptoms. RCVS can be primary or secondary to several factors. Here, we present a case of RCVS in a patient with systemic scleroderma. A 44-year-old female patient presented to the hospital due to Raynaud’s phenomenon, fingertip pain ulceration, skin tightness, and skin depigmentation. She was diagnosed with systemic scleroderma. After four days of steroids, immunosuppressants (mycophenolate mofetil), and hydroxychloroquine, the patient developed severe thunderclap headaches and left lower extremity weakness. The computed tomography angiography (CTA) showed multifocal segmental vasoconstriction of the cerebral arteries. The patient’s headache and body weakness resolved after starting an oral calcium channel blocker (nimodipine).

Reversible cerebral vasoconstriction syndrome in children: an update

Headaches are one of the most common neurologic complaints leading to emergency room visits in pediatric patients. Of the different type of headache presentations, thunderclap headaches require a particularly urgent work-up. In children, recurrent thunderclap headaches are more often associated with reversible cerebral vasoconstriction syndrome (RCVS) than other etiologies such as subarachnoid hemorrhage. RCVS is a vascular disorder of incompletely understood etiology, characterized by diffuse vasoconstriction of the cerebral arterial vasculature, and commonly associated with recurrent severe headaches. Patients may experience focal neurological deficits, due to hemorrhages, infarcts, and even posterior reversible encephalopathy syndrome . Although RCVS has been best characterized in adults, it does occur in children. This review summarizes the presentation of RCVS in children and highlights some of the differences with the adult population.

Fatal reversible cerebral vasoconstriction syndrome: An unusual presentation of a rare disease

The reversible cerebral vasoconstriction syndrome is a variable, segmental, and multifocal constriction of brain arteries, usually with a benign course. We describe the case of a 49-year-old woman who presented with headaches, visual symptoms, and seizures. Three days after admission, vasoconstriction areas were found in at least two vascular territories in two segments of the same arteries. The patient was admitted to the intensive care unit where her blood pressure was monitored and she received medical treatment. Surprisingly, the patient presented an unpredicted evolution in developing malignant cerebral edema on the seventh day after admission. She then suffered brain death and was taken to organ donation. A guided nervous system necropsy was later performed. The pathology discarded vasculitis and exhibited hemorrhage areas in the cerebral convexity. Herein, we discuss the most relevant aspects of cases with fulminant evolution reported in the literature. The reversible cerebral vasoconstriction syndrome is usually associated with fatal outcomes when patients exhibit focalization, their first neuroimaging typically shows disturbances, and a rapid clinical deterioration occurs. It is crucial to identify factors linked to poor prognosis and set intervention strategies and early prevention.

Profiling cerebrovascular function in migraine: A systematic review and meta-analysis

Previous studies have investigated whether migraine is a circulatory disorder, as migraineurs are at heightened risk of cerebrovascular disease. However, in most cases, systemic vascular function was evaluated, which may not reflect abnormalities in the cerebral circulation. Therefore, we aimed to determine whether cerebrovascular function differs between migraineurs and controls. A systematic literature search was conducted across three electronic databases to search for studies that compared cerebrovascular function in migraineurs to controls. Where applicable, meta-analyses were used to determine standardised mean differences (SMD) between migraineurs and controls. Seventy articles were identified, 40 of which contained quantitative data. Meta-analyses showed pulsatility index (PI) was higher (SMD = 0.23; 95%CI = 0.05 to 0.42, P = 0.01) and cerebrovascular responsiveness (CVR) to hypercapnia was lower (SMD=-0.34; 95%CI=-0.67 to -0.01, P = 0.04) in the posterior circulation of migraineurs, particularly those without aura. The meta-analyses also indicated that migraineurs have higher resting mean blood flow velocity in both anterior (SMD = 0.14; 95%CI = 0.05 to 0.23, P = 0.003) and posterior circulations (SMD = 0.20; 95%CI = 0.05 to 0.34, P = 0.007). Compared to healthy controls, migraineurs have altered cerebrovascular function, evidenced by elevated PI (representing arterial stiffness) and impaired CVR to hypercapnia (representing cerebral vasodilator function). Future studies should investigate whether improvement of cerebrovascular function is able to alleviate migraine.

Post-reversible cerebral vasoconstriction syndrome headache

Background

Chronic headache may persist after the remission of reversible cerebral vasoconstriction syndrome (RCVS) in some patients. We aimed to investigate the prevalence, characteristics, risk factors, and the impact of post-RCVS headache.

Methods

We prospectively recruited patients with RCVS and collected their baseline demographics, including psychological distress measured by Hospital Anxiety and Depression scale. We evaluated whether the patients developed post-RCVS headache 3 months after RCVS onset. The manifestations of post-RCVS headache and headache-related disability measured by Migraine Disability Assessment (MIDAS) scores were recorded.

Results

From 2017 to 2019, 134 patients with RCVS were recruited, of whom, 123 finished follow-up interviews (response rate 91.8%). Sixty (48.8%) patients had post-RCVS headache. Migrainous features were common in post-RCVS headache. Post-RCVS headache caused moderate-to-severe headache-related disability (MIDAS score > 10) in seven (11.7%) patients. Higher anxiety level (odds ratio 1.21, p = 0.009) and a history of migraine (odds ratio 2.59, p = 0.049) are associated with post-RCVS headache. Survival analysis estimated that 50% post-RCVS headache would recover in 389 days (95% confidence interval: 198.5–579) after disease onset.

Conclusions

Post-RCVS headache is common, affecting half of patients and being disabling in one-tenth. Higher anxiety level and migraine history are risk factors. Half of the patients with post-RCVS headache would recover in about a year.

[Headache and cerebrovascular diseases]

Headache is a common symptom of acute and chronic cerebrovascular diseases. Headache can be symptomatic in patients with various forms of vascular pathology of the brain but primary headaches are much more common. Secondary headaches in acute cerebrovascular accidents may be the first symptom, and in some cases, a risk factor or complication of stroke. In chronic cerebrovascular diseases, headache may be the predominant symptom in the early stages and resolve in the later stages of the disease. At the same time, the severity, nature and course of headache cannot be considered as reliable signs of cerebrovascular disease. Meanwhile, the verification of the headache form is important from the point of view of determining the priorities of diagnosis and therapy.

Narrative Review: Headaches After Reversible Cerebral Vasoconstriction Syndrome

PURPOSE OF REVIEW

Reversible cerebral vasoconstriction syndrome (RCVS) is a disorder with distinct features: recurrent thunderclap headaches with reversible vasoconstriction of intracranial arteries. Substantial studies regarding outcomes after RCVS were conducted, showing favorable functional outcomes in most patients despite the potentially life-threatening complications of RCVS, including ischemic stroke, intracranial hemorrhage, or convexity subarachnoid hemorrhage. However, patients may report headaches after the resolution of RCVS while relative studies were scarce.

RECENT FINDINGS

Two prospective studies from different cohorts consistently revealed that RCVS recurred in at least 5% of patients. Patients with prior migraine history and patients whose thunderclap headaches are elicited by sexual activity or exertion are at higher risk for RCVS recurrence. On the other hand, several retrospective studies and case reports reported that chronic headaches are common in RCVS patients after the resolution of acute bouts. The chronic headaches after RCVS are sometimes disabling in certain patients. Headaches after RCVS are not uncommon but usually overseen. Medical attention and examinations are warranted in patient with RCVS who reported recurrence of thunderclap headaches or chronic headaches after RCVS.

Headache in cerebrovascular diseases

Headache is a common accompanying symptom of cerebrovascular diseases. The most common patterns of headache for different cerebrovascular disorders, aetiology and pathogenesis and diagnostic workup are reviewed with emphasis on distinguishing characteristics. It will be a clinical guide for physicians who treat patients with headache or cerebral vascular disease.

Fatal reversible cerebral vasoconstriction syndrome: A systematic review of case series and case reports

OBJECTIVE

To describe patient characteristics, radiological findings and the clinical course of adults with fatal reversible cerebral vasoconstriction syndrome (RCVS).

METHODS

A systematic literature search from January 1, 2000, until December 31, 2018, was performed using PubMed, EMBASE, Scopus, Cochrane reviews, LILACS and Scielo. Studies reporting RCVS in adult patients with fatal outcomes were included.

RESULTS

430 studies were initially identified, 179 full-text articles were reviewed, and 9 publications describing 12 subjects were included. The vast majority of the reports were from the U.S. Most of the female cases occurred during postpartum. All patients had a headache on initial presentation, although only 42% had thunderclap headache. A CT scan was performed on 67% of the patients. Imaging results were diverse, with a tendency toward cerebral hemorrhage followed by mixed cases. The main course of treatment included steroids (58% of the patients), with only 42% receiving nimodipine. The time to death ranged from 4 to 14 days, with a median of 9.2 days (SD ± 3.2).

CONCLUSION

We found that the majority of fatal cases reported in the literature are most likely related to postpartum angiopathy. We established a tendency in the onset of brain hemorrhage and the combination of infarction and brain hemorrhage. We described various markers for poor prognosis, including focal signs, the presence of hemorrhage and infarct in the first diagnostic image obtained and the need for invasive interventions. The majority of fatal cases in our report occurred in women, with over half of those cases during the puerperium period.

Reversible Cerebral Vasoconstriction Syndrome Associated with Coronary Artery Vasospasm

Reversible cerebral vasoconstriction syndrome is a rare disorder associated with neurologic symptoms secondary to diffuse cerebral vasospasm. Cardiac involvement in this disease is exceedingly rare. A 50-year-old woman was admitted to our hospital for evaluation of chest pain. During a 3-year period, she had been admitted multiple times because of chest pain and elevated serum cardiac enzymes. Transthoracic echocardiograms showed transient wall-motion abnormalities; however, coronary angiograms revealed no coronary artery disease. At the current admission, she had a thunderclap headache, and cerebral angiograms revealed diffuse cerebral vasoconstriction that improved after verapamil infusion, confirming the diagnosis of reversible cerebral vasoconstriction syndrome. The patient was treated successfully with oral diltiazem and had no recurrence of symptoms. We describe what we think is the first reported case of coronary artery spasm in association with reversible cerebral vasoconstriction syndrome. Future research should be focused on identifying treatment options and defining the mechanisms by which the cerebral and coronary vasculature are affected.

Reversible cerebral vasoconstriction syndrome in paediatric patients with systemic lupus erythematosus: implications for management

Microvascular brain injury is well recognized in neuropsychiatric systemic lupus erythematosus (SLE), but cerebral large artery involvement is being debated. Three females with SLE, aged 9 to 14 years, had immunosuppressive treatment intensification because of lupus nephritis. Within the following days or weeks, they presented with intense cephalalgia - isolated or associated with neurological symptoms - and no or mild hypertension. Magnetic resonance angiography showed multiple stenoses within the circle of Willis. One patient had subsequent small subcortical cerebral infarction. Two patients were treated for neuropsychiatric SLE; one patient was treated for reversible cerebral vasoconstriction syndrome (RCVS). Angiography normalized within a few weeks in all three patients. Retrospectively, clinical and radiological features suggest that RCVS was the most likely diagnosis in all patients. Multidisciplinary analysis of clinical and angiographic features is recommended, as RCVS is rare in children and its recognition may help to adjust treatment. WHAT THIS PAPER ADDS: Reversible vasoconstriction syndrome was observed in paediatric systemic lupus erythematosus. Thorough imaging analysis was necessary to address this diagnosis in paediatric patients.

Influence of Climate on the Incidence of RCVS - A Retrospective Study From Taiwan

BACKGROUND

Cold weather is reportedly a precipitator of reversible cerebral vasoconstriction syndrome (RCVS) in a few cases. We systematically investigated whether meteorological factors correlate with the occurrence of RCVS.

METHODS

We conducted a retrospective analysis of a cohort of patients diagnosed with RCVS or probable RCVS, based on International Classification of Headache Disorders, third edition (ICHD-3) criteria, in a hospital-based headache center from March 2005 to February 2014. Monthly averages of local weather data measured in Taipei were obtained from the Central Weather Bureau in Taiwan. Primary weather variables were compared with the number of monthly new-onset cases of RCVS.

RESULTS

We recruited 226 patients with established RCVS and 72 patients with probable RCVS during a 108-month study period. Incidence of RCVS was higher in winter than summer months (3.3 persons/month [SD: 2.0] vs 2.1 persons/month [SD: 1.5], P = .013). The monthly incidence of RCVS correlated negatively with mean daily temperature (r = -0.231, P = .016) and average precipitation (r = -0.269, P = .005), but positively with barometric pressure (r = 0.274, P = .004). These 3 correlated meteorological factors together explained about 10% of the variance in RCVS monthly incidence (R²  = 0.095, P = .015).

CONCLUSION

RCVS was found to be more common in winter months and to be associated with weather variables in Taiwan. Further studies are needed to explore the underlying mechanisms of these associations.