The long-term effect of work schedule, shift work disorder, insomnia and restless legs syndrome on headache among nurses: A prospective longitudinal cohort study.

BACKGROUND: The preset study aimed to explore whether work schedules and sleep disorders predict the onset of headache. METHODS: A longitudinal study was conducted with questionnaire data from 2014 (baseline) and 2017 (follow-up) on work schedule, number of night shifts, number of quick returns, insomnia, shift work disorder (SWD), restless legs syndrome (RLS) and validated headache diagnoses among 1560 Norwegian nurses. Associations were explored by multivariate regression analyses. RESULTS: Work related factors at baseline did not predict onset of headache three years later. In the adjusted logistic regressions, insomnia at baseline predicted increased risk of new onset of migraine (odds ratio (OR) = 1.58; 95% confidence interval (CI) = 1.08-2.33), chronic headache (OR = 2.02; 95% CI = 1.04-4.66) and medication-overuse headache (OR = 3.79; 95% CI = 1.26-11.42) at follow-up. SWD at baseline predicted new onset of migraine (OR = 1.64; 95% CI = 1.07-2.50) and RLS at baseline predicted new onset of headache ≥1 day per month (OR = 1.55; 95% CI = 1.01-2.36) and migraine (OR = 1.55; 95% CI = 1.03-2.32) at follow-up. No factors predicted tension-type headache. CONCLUSIONS: Overall, work related factors did not predict the onset of headache three years later, whereas insomnia, SWD and RLS at baseline all increased the risk of future headaches.

Headaches and facial pain attributed to SARS-CoV-2 infection and vaccination: a systematic review.

BACKGROUND AND PURPOSE: The aim was to provide insights to the characteristics of headache in the context of COVID-19 on behalf of the Headache Scientific Panel and the Neuro-COVID-19 Task Force of the European Academy of Neurology (EAN) and the European Headache Federation (EHF). METHODS: Following the Delphi method the Task Force identified six relevant questions and then conducted a systematic literature review to provide evidence-based answers and suggest specific diagnostic criteria. RESULTS: No data for facial pain were identified in the literature search. (1) Headache incidence during acute COVID-19 varies considerably, with higher prevalence rates in prospective compared to retrospective studies (28.9%-74.6% vs. 6.5%-34.0%). (2) Acute COVID-19 headache is usually bilateral or holocranial and often moderate to severe with throbbing pain quality lasting 2-14 days after first signs of COVID-19; photo-phonophobia, nausea, anosmia and ageusia are common associated features; persistent headache shares similar clinical characteristics. (3) Acute COVID-19 headache is presumably caused by immune-mediated mechanisms that activate the trigeminovascular system. (4) Headache occurs in 13.3%-76.9% following SARS-CoV-2 vaccination and occurs more often amongst women with a pre-existing primary headache; the risk of developing headache is higher with the adenoviral-vector-type vaccines than with other preparations. (5) Headache related to SARS-CoV-2 vaccination is mostly bilateral, and throbbing, pressing, jolting or stabbing. (6) No studies have been conducted investigating the underlying mechanism of headache attributed to SARS-CoV-2 vaccines. CONCLUSION: The results of this joint EAN/EHF initiative provide a framework for a better understanding of headache in the context of SARS-CoV-2 infection and vaccination.

Changes in work schedule affect headache frequency among Norwegian nurses: a 3-year-follow-up study.

OBJECTIVES: To explore whether changes in work schedule, number of night shifts and number of quick returns were related to changes in headache frequencies. METHODS: A longitudinal study with questionnaire data from 2014 (baseline) and 2017 (follow-up) on work schedule (day only, shift work without nights and shift work with nights), number of night shifts, number of quick returns (less than 11 hours in-between shifts) and validated headache diagnoses among 1104 Norwegian nurses. Associations were explored by adjusted multivariate regression analyses. RESULTS: The median age at baseline was 37 years (IQR 31-43) and 90.5% were women. In the adjusted logistic regression analysis of changed work schedule between baseline and follow-up, changing from night work was associated with increased odds for reversion from headache >1 days/month to no headache at all last year (OR 2.77 (1.29; 5.95)). Changes towards less night shifts (>10) or quick returns (>10) during the last year were associated with increased odds of reversion of headache to no headache (OR 2.23 (1.20; 4.17) and OR 1.90 (1.04; 3.49)). Only decrease in number of night shifts (>10) during the last year reduced risk of onset of any new headache between baseline and follow-up (OR of 0.39 (0.18; 0.84)). CONCLUSION: Changing from night work and reducing the number of night shifts and quick returns were associated with less headache in this 3-year-follow-up of Norwegian nurses. This adds to the growing body of evidence that night work may have direct negative health consequences.

Prehospital Blood Pressure and Clinical and Radiological Outcomes in Acute Spontaneous Intracerebral Hemorrhage.

BACKGROUND: High blood pressure (BP) is associated with poor outcome in acute spontaneous intracerebral hemorrhage. Little is known about the predictive value of prehospital BP in intracerebral hemorrhage. We aimed to investigate the relationship between prehospital BP and clinical and radiological outcomes. METHODS: This is a retrospective, hospital-based study of all adult intracerebral hemorrhage patients admitted within 24 hours of symptom onset to a large primary stroke centre during 2012 to 2019. The first prehospital and on-admission BP were recorded as systolic BP, diastolic BP, mean arterial pressure, and pulse pressure. The absolute differences between prehospital and on-admission BP were calculated (BPchange). Primary outcomes were in-hospital death, early neurological deterioration, and hematoma expansion. Associations between prehospital BP, BPchange, and outcomes were explored by regression with adjustment for relevant confounders. RESULTS: We included 426 patients aged median 76 (interquartile range 67-85) years and 203 (48%) were female. Median prehospital systolic BP was 179 (interquartile range 158-197) and diastolic BP was 100 (interquartile range 86-112) mm Hg. In-hospital death occurred in 121/426 (28%), early neurological deterioration in 107/295 (36%), and hematoma expansion in 50/185 (27%) patients. There were linear associations between 5 mm Hg increment of prehospital systolic BP (odds ratio 1.06, [95% CI, 1.01-1.12]) and mean arterial pressure (odds ratio 1.08, [95% CI, 1.01-1.15]) and in-hospital death, and between 5 mm Hg increment of prehospital diastolic BP (odds ratio 1.10, [95% CI, 1.00-1.21]) and mean arterial pressure (odds ratio 1.09, [95% CI, 1.00-1.18]) and hematoma expansion. There was a nonlinear association between prehospital systolic BP and in-hospital death. No consistent associations between prehospital BPchange and outcomes were found. CONCLUSIONS: In patients with acute intracerebral hemorrhage, elevated prehospital BP parameters were associated with in-hospital death and hematoma expansion. Changes in prehospital BP were not consistently associated with outcome. A possible U-shaped association between prehospital BP and in-hospital death needs further investigation.

Telemedicine in headache care: A systematic review.

OBJECTIVE: Telemedicine is defined as video-based consultations with synchronous video and sound. This systematic review investigated the use of telemedicine for headache patients. The primary outcomes of interest were treatment efficacy, feasibility, safety, convenience, compliance, and patient satisfaction. METHODS: A systematic literature search was performed using PubMed and Embase. Thirteen articles met the eligibility criteria and were included in the review. A systematic review protocol was registered on the International Prospective Register of Systematic Reviews, registration number CRD42021265875. RESULTS: There were no significant differences in treatment efficacy, patient satisfaction, compliance or safety using telemedicine when compared to traditional consultations. Telemedicine was found to be convenient due to being less time-consuming and expensive, especially for patients with limited access to health care. Despite the frequent occurrence of technical errors, telemedicine was found to be feasible. CONCLUSION: Telemedicine consultations are similar in quality to traditional in-office headache consultations and can be a more convenient solution for eligible headache patients.

Reasons and predictors of non-thrombolysis in patients with acute ischemic stroke admitted within 4.5 h.

OBJECTIVES: Thrombolytic treatment in acute ischemic stroke (AIS) reduces stroke-related disability. Nearly 40% of all patients with AIS (<4.5 h) receive thrombolysis, but there is a large variation in the use between hospitals. Little is known about reasons and predictors for not giving thrombolytic treatment. Therefore, we aimed to investigate reasons for non-thrombolysis in patients admitted within 4.5 h. METHODS: All patients with AIS (<4.5 h) admitted to Akershus University Hospital, Norway, between January 2015 and December 2017 were examined. Patient characteristics and reasons for not giving thrombolysis were registered. Descriptive statistics and logistic regression analyses were performed. RESULTS: Of 535 patients admitted with AIS (<4.5 h), 250 (47%) did not receive thrombolysis and of these only 26% had an absolute contraindication to treatment. Among the 74% with relative contraindications, the most common reasons given were mild and improving symptoms. Previous stroke (OR 3.32, 95%CI 1.99-5.52), arriving between 3 h and 4.5 h after onset (OR 7.76, 95%CI 3.73-16.11) or having mild symptoms (OR 2.33, 95%CI 1.56-3.49) were all significant predictors of not receiving thrombolytic treatment in the multivariable logistic regression model. CONCLUSION: A large proportion of patients with AIS do not receive thrombolysis. This study highlights up-to-date findings that arriving late in the time window, mild symptoms, and previous stroke are strong predictors of non-treatment. It is uncertain whether there is an underuse of thrombolysis in AIS. Increasing the utility of thrombolysis in the 4.5 h time window must be weighed against possible harms.

The Norwegian PraksisNett: a nationwide practice-based research network with a novel IT infrastructure.

PURPOSE: Clinical research in primary care is relatively scarce. Practice-based research networks (PBRNs) are research infrastructures to overcome hurdles associated with conducting studies in primary care. In Norway, almost all 5.4 million inhabitants have access to a general practitioner (GP) through a patient-list system. This gives opportunity for a PBRN with reliable information about the general population. The aim of the current paper is to describe the establishment, organization and function of PraksisNett (the Norwegian Primary Care Research Network). MATERIALS AND METHODS: We describe the development, funding and logistics of PraksisNett as a nationwide PBRN. RESULTS: PraksisNett received funding from the Research Council of Norway for an establishment period of five years (2018-2022). It is comprised of two parts; a human infrastructure (employees, including academic GPs) organized as four regional nodes and a coordinating node and an IT infrastructure comprised by the Snow system in conjunction with the Medrave M4 system. The core of the infrastructure is the 92 general practices that are contractually linked to PraksisNett. These include 492 GPs, serving almost 520,000 patients. Practices were recruited during 2019-2020 and comprise a representative mix of rural and urban settings spread throughout all regions of Norway. CONCLUSION: Norway has established a nationwide PBRN to reduce hurdles for conducting clinical studies in primary care. Improved infrastructure for clinical studies in primary care is expected to increase the attractiveness for studies on the management of disorders and diseases in primary care and facilitate international research collaboration. This will benefit both patients, GPs and society in terms of improved quality of care.Key pointsPractice-based research networks (PBRNs) are research infrastructures to overcome hurdles associated with conducting studies in primary careImproved infrastructure for clinical studies in primary care is expected to increase the attractiveness for studies on the management of disorders and diseases in primary care and facilitate international research collaborationWe describe PraksisNett, a Norwegian PBRN consisting of 92 general practices including 492 GPs, serving almost 520,000 patientsAn advanced and secure IT infrastructure connects the general practices to PraksisNett and makes it possible to identify and recruit patients in a novel way, as well as reuse clinical dataPraksisNett will benefit both patients, GPs and society in terms of improved quality of careThis paper may inform and inspire initiatives to establish PBRNs elsewhere.

Barriers and gaps in headache education: a national cross-sectional survey of neurology residents in Denmark.

BACKGROUND: A major barrier to adequate headache care is the relative lack of formal education and training of healthcare professionals. Concerted efforts should be made to pinpoint major gaps in knowledge in healthcare professionals to facilitate better educational policies in headache training. The aim of this study was to identify deficiencies and barriers in headache training among residents in neurology in Denmark. METHODS: We conducted a national cross-sectional survey of residents in neurology in Denmark from April 2019 to September 2019. The survey included questions on participant demographics, knowledge of and barriers in headache disorders, guidelines and diagnostic tools usage, contact with primary and tertiary care, medication overuse, and non-pharmacological interventions. Furthermore, respondents were asked to provide a ranked list from most to least interesting for six sub-specializations/disorders, i.e., cerebrovascular disease, dementia, epilepsy, headache, multiple sclerosis, Parkinson's disease. RESULTS: Sixty (40%) out of estimated a population of ~ 150 resident across Denmark accepted the invitation. Of these, 54/60 (90%) completed the survey. Although two-thirds, 35/54 (65%), of the respondents had prior formalized training in headache disorders, we identified gaps in all explored domains including diagnosis, management, and referral patterns. Particularly, there was an inconsistent use of guidelines and diagnostic criteria from the Danish Headache Society (2.74 (± 1.14)), the Danish Neurological Society (3.15 (± 0.86)), and the International Classification of Headache Disorders (2.33 (± 1.08)); 1: never/have not heard of, 4: always. Headache was ranked second to last out of six sub-specializations in interest. CONCLUSIONS: Overall knowledge on headache disorders amongst neurology residents in Denmark do not meet the expectations set out by national and international recommendations. Stakeholders should make strategic initiatives for structured education in headache for improved clinical outcomes in parallel with costs reduction through resource optimization.

Perceptions on basilar artery occlusion management in China versus other countries: Analysis of the after the BEST of BASICS (ABBA) survey.

INTRODUCTION: Uncertainty remains on the optimal management of basilar artery occlusion (BAO). Two large randomized controlled trials (RCTs) in 2019 and 2021 demonstrated neutral results with respect to the use of endovascular therapy (EVT) for BAO. This study aimed to understand regional variation in physicians' perceptions towards the treatment of BAO as stratified by physician respondents from China versus outside China, prior to the publication of studies demonstrating a benefit of EVT for BAO. METHODS: An international online survey was conducted of stroke neurologists and neurointerventionalists from January to March 2022. Survey questions evaluated physician opinions toward the use of EVT in BAO, as well as the clinical and imaging features underlying treatment decisions. Respondents were dichotomized as either from China or from other countries and differences between groups were analyzed. RESULTS: There were 1245 physician respondents across 73 countries of which 295 (23.7%) were from China. Compared to respondents from the rest of the world, respondents from China were more likely to be interventionalists (71.5% vs 35.0%; p < 0.0001). Overall, more than 95% of respondents believed that EVT was superior to medical therapy under certain circumstances. Chinese respondents were more likely to believe that further RCTs were necessary than respondents from other countries (93.6% vs 76.2%; p < 0.0001). Chinese respondents were more likely to use advanced imaging in later time windows and use a premorbid mRS threshold of ≤2 for BAO selection to EVT. CONCLUSION: Most stroke physicians believe EVT is beneficial in selected patients with BAO. Clinical and imaging modality differences were observed in the selection criteria used for EVT. There was greater inclination to enroll all trial eligible patients in a BAO RCT by respondents from China as compared to other parts of the world.

Management of cluster headache and other trigeminal autonomic cephalalgias in pregnancy and breastfeeding.

Many clinicians lack experience in managing trigeminal autonomic cephalalgias (TACs) in pregnancy and lactation. In addition to cluster headache, TACs include hemicrania continua, paroxysmal hemicrania, and short-lasting unilateral neuralgiform headache with conjunctival injection and tearing/autonomic symptoms (SUNCT/SUNA). Treating these rare, severe headache conditions often requires off-label drugs that have uncertain teratogenic potential. In the last few years, several new treatment options and safety documentation have emerged, but clinical guidelines are lacking. This narrative review aimed to provide an updated clinical guide and good clinical practice recommendations for the management of these debilitating headache disorders in pregnancy and lactation.

Green Flags and headache: A concept study using the Delphi method.

OBJECTIVE: The aim of this study was to collect and rate Green Flags, that is, symptoms or pieces of information indicating that a patient is more likely to suffer from a primary than from a secondary headache. BACKGROUND: When assessing headaches, a central question to be answered is whether the pain is primary or secondary to another disorder. To maximize the likelihood of a correct diagnosis, relevant signs and symptoms must be sought, identified, and weighed against each other. METHODS: The project was designed as a Delphi study. In the first round, an expert panel proposed green flags that were rated anonymously in two subsequent rounds. Proposals with an average rating of 4.0 and higher on a scale from 0 to 5 reached consensus. RESULTS: Five Green Flags reached consensus: (i) "The current headache has already been present during childhood"; (ii) "The headache occurs in temporal relationship with the menstrual cycle"; (iii) "The patient has headache-free days"; (iv) "Close family members have the same headache phenotype"; and (v) "Headache occurred or stopped more than one week ago." CONCLUSIONS: We propose five Green Flags for primary headache disorders. None being a pathognomonic sign, we recommend searching for both Green Flags and Red Flags. If both are present, a secondary headache should be suspected. Overall, the application of the Green Flag concept in clinical practice is likely to increase diagnostic accuracy and improve diagnostic resource allocation. Prospective studies in clinical populations should be conducted to validate these Green Flags.

Acute stroke care during the first phase of COVID-19 pandemic in Norway.

OBJECTIVES: The aim of the present study was to investigate how the initial phase of the COVID-19 pandemic affected the hospital stroke management and research in Norway. MATERIALS AND METHODS: All neurological departments with a Stroke Unit in Norway (n = 17) were invited to participate in a questionnaire survey. The study focused on the first lockdown period, and all questions were thus answered in regard to the period between 12 March and 15 April 2020. RESULTS: The responder rate was 94% (16/17). Eighty-one % (13/16) reported that the pandemic affected their department, and 63% (10/16) changed their stroke care pathways. The number of new acute admissions in terms of both strokes and stroke mimics decreased at all 16 departments. Fewer patients received thrombolysis and endovascular treatment, and multidisciplinary stroke rehabilitation services were less available. The mandatory 3 months of follow-up of stroke patients was postponed at 73% of the hospitals. All departments conducting stroke research reported a stop in ongoing projects. CONCLUSION: In Norway, hospital-based stroke care and research were impacted during the initial phase of the COVID-19 pandemic, with likely repercussions for patient care and outcomes. In the future, stroke departments will require contingency plans in order to protect the entire stroke treatment chain.

Stroke admission rates before, during and after the first phase of the COVID-19 pandemic.

BACKGROUND: There was a significant decrease in stroke admissions during the first phase of the COVID-19 pandemic. There are concerns that stroke patients have not sought medical attention and in the months after the lockdown suffer recurrent severe strokes. The aims of this study were to investigate how stroke admission rates and distributions of severity varied before, during and after the lockdown in a representative Norwegian hospital population. METHODS: All patients discharged from Akershus University Hospital with a diagnosis of transient ischemic attack (TIA) or acute stroke from January to September 2020 were identified by hospital chart review. RESULTS: We observed a transient decrease in weekly stroke admissions during lockdown from an average of 21.4 (SD 4.7) before to 15.0 (SD 4.2) during and 17.2 (SD 3.3) after (p < 0.011). The proportion of mild ischemic and haemorrhagic strokes was also lower during lockdown with 66% before, 57% during and 68% after (p = 0.011). CONCLUSION: The period of COVID-19 lockdown was associated with a temporary reduction in total admissions of strokes. In particular, there were fewer with TIA and mild stroke. Given the need to prevent the worsening of symptoms and risk of recurrence, it is necessary to emphasise the importance to seek medical care even in states of emergency.

The patterns and burden of multimorbidity in geriatric patients with prolonged use of addictive medications.

BACKGROUND: Multimorbidity and prolonged use of addictive medications are prevalent among older patients, and known to increase the risk of adverse drug events. Yet, the relationship between these two entities has remained understudied. AIMS: This study explored the association between multimorbidity burden and prolonged use of addictive medications in geriatric patients, adjusted for clinically important covariates. Furthermore, we identified comorbidity patterns in prolonged users. METHODS: We conducted a cross-sectional study on a consecutive sample of 246 patients, aged 65-90 years, admitted to a large public university hospital in Norway. We defined prolonged use of addictive medications as using benzodiazepines, opioids and/or z-hypnotics beyond the duration recommended by clinical guidelines (≥ 4 weeks). Multimorbidity was assessed with the Cumulative Illness Rating Scale for Geriatrics (CIRS-G), based on diagnoses made by independent physicians. RESULTS: Compared to non-prolonged use, prolonged use was significantly more common among patients who had psychiatric (19/27, 70%), liver (19/22, 86%), upper gastrointestinal tract (21/32, 66%), musculoskeletal (52/96, 54%), or nervous system disorders (46/92, 50%). Patients with prolonged use had a higher multimorbidity burden than those without such use (CIRS-G score, mean = 7.7, SD = 2.7 versus mean = 4.6, SD = 2.2, p < 0.001). Multivariable logistic regression indicated a significant association between multimorbidity burden and prolonged addictive medication use (OR = 1.72, 95% CI 1.42-2.08). Predictive margins postestimation showed a systematic increase in the predicted CIRS-G scores when the number of addictive drug used increases. CONCLUSIONS: Multimorbidity is strongly associated with prolonged use of addictive medications. Multiple substance use may aggravate disease burden of older patients.

Is there a causal relationship between stress and migraine? Current evidence and implications for management.

BACKGROUND: The purpose of this narrative review is to examine the literature investigating a causal relationship between stress and migraine and evaluate its implications for managing migraine. METHODS: PubMed, PsycINFO and CINAHL were searched from 1988 to August 2021, identifying 2223 records evaluating the relationship between stress and migraine. Records were systematically screened. All potentially relevant records were thematically categorized into six mechanistic groups. Within each group the most recent reports providing new insights were cited. RESULTS: First, studies have demonstrated an association of uncertain causality between high stress loads from stressful life events, daily hassles or other sources, and the incidence of new-onset migraine. Second, major stressful life events seem to precede the transformation from episodic to chronic migraine. Third, there is some evidence for changes in levels of stress as a risk factor for migraine attacks. Research also suggests there may be a reversed causality or that stress-trigger patterns are too individually heterogeneous for any generalized causality. Fourth, migraine symptom burden seems to increase in a setting of stress, partially driven by psychiatric comorbidity. Fifth, stress may induce sensitization and altered cortical excitability, partially explaining attack triggering, development of chronic migraine, and increased symptom burden including interictal symptom burden such as allodynia, photophobia or anxiety. Finally, behavioral interventions and forecasting models including stress variables seem to be useful in managing migraine. CONCLUSION: The exact causal relationships in which stress causes incidence, chronification, migraine attacks, or increased burden of migraine remains unclear. Several individuals benefit from stress-oriented therapies, and such therapies should be offered as an adjuvant to conventional treatment and to those with a preference. Further understanding the relationship between stress, migraine and effective therapeutic options is likely to be improved by characterizing individual patterns of stress and migraine, and may in turn improve therapeutics.

The management and clinical knowledge of headache disorders among general practitioners in Norway: a questionnaire survey.

BACKGROUND: General practitioners (GPs) diagnose and manage a majority of headache patients seeking health care. With the aim to understand the potential for clinical improvement and educational needs, we performed a study to investigate Norwegian GPs knowledge about headache and its clinical management. METHODS: We invited GPs from a random sample of 130 Norwegian continuous medical education (CME) groups to respond to an anonymous questionnaire survey. RESULTS: 367 GPs responded to the survey (73% of invited CME groups, 7.6% of all GPs in Norway). Mean age was 46 (SD 11) years, with an average of 18 (SD 10) years of clinical experience. In general the national treatment recommendations were followed, while the International Classification of Headache Disorders and other international guidelines were rarely used. Overall, 80% (n = 292) of the GPs suggested adequate prophylactic medication for frequent episodic migraine, while 28% (n = 101) suggested adequate prophylactic medication for chronic tension-type headache (CTTH). Half (52%, n = 191)) of the respondents were aware that different types of acute headache medication can lead to medication-overuse headache (MOH), and 59% (n = 217) knew that prophylactic headache medication does not lead to MOH. GPs often used MRI in the diagnostic work-up. GPs reported that lack of good treatment options was a main barrier to more optimized treatment of headache patients. CONCLUSION: The knowledge of management of CTTH and MOH was moderate compared to migraine among Norwegian GPs.

Delayed headache after COVID-19 vaccination: a red flag for vaccine induced cerebral venous thrombosis.

BACKGROUND: Headache is a frequent symptom following COVID-19 immunization with a typical onset within days post-vaccination. Cases of cerebral venous thrombosis (CVT) have been reported in adenovirus vector-based COVID-19 vaccine recipients. FINDINGS: We reviewed all vaccine related CVT published cases by April 30, 2021. We assessed demographic, clinical variables and the interval between the vaccination and onset of headache. We assessed whether the presence of headache was associated with higher probability of death or intracranial hemorrhage. We identified 77 cases of CVT after COVID-19 vaccination. Patients' age was below 60 years in 74/77 (95.8%) cases and 61/68 (89.7%) were women. Headache was described in 38/77 (49.4%) cases, and in 35/38 (92.1%) was associated with other symptoms. Multiple organ thrombosis was reported in 19/77 (24.7%) cases, intracranial hemorrhage in 33/77 (42.9%) cases and 19/77 (24.7%) patients died. The median time between vaccination and CVT-related headache onset was 8 (interquartile range 7.0-9.7) days. The presence of headache was associated with a higher odd of intracranial hemorrhage (OR 7.4; 95% CI: 2.7-20.8, p < 0.001), but not with death (OR: 0.51, 95% CI: 0.18-1.47, p = 0.213). CONCLUSION: Delayed onset of headache following an adenovirus vector-based COVID-19 vaccine is associated with development of CVT. Patients with new-onset headache, 1 week after vaccination with an adenovirus vector-based vaccine, should receive a thorough clinical evaluation and CVT must be ruled out.

Incidence and Mortality of Cerebral Venous Thrombosis in a Norwegian Population.

BACKGROUND AND PURPOSE: There are conflicting figures of the incidence of cerebral venous thrombosis (CVT). The incidence was previously estimated to around 0.5/100 000/y, but more recent studies have suggested 1 to 1.5/100 000/y. The purpose of this study was to explore the incidence and mortality of CVT in a Norwegian population. METHODS: A retrospective cross-sectional hospital population-based study conducted at Akershus University Hospital serving roughly 10% of the total Norwegian population. Patients were identified through chart reviews based on the relevant International Classification of Diseases(Tenth Revision) codes for new CVT cases in a 7-year period between January 1, 2011, and December 31, 2017. Only inhabitants living in the hospital's catchment area were included. RESULTS: Sixty-two patients aged 0 to 80 years were identified and included. The median age was 46 years and 53% were females. The overall incidence of CVT was 1.75 (95% CI, 1.36-2.23) per 100 000/y with no significant sex differences. The incidence for children and adolescents (<18 years, n=9) was lower than for adults (≥18 years, n=53); 1.08 (0.52-1.97) versus 1.96 (1.49-2.55) per 100 000/y per year, with the highest incidence for those >50 years with 2.10 (1.38-3.07)/100 000/y. Headache was the most prevalent symptom, reported in 83%, followed by nausea, motor deficits, and seizures observed in 45%, 32%, and 32% of the patients. Transverse sinuses and the jugular vein were the most frequent sites of thrombosis. In most patients (61%), thrombosis occurred in multiple sinuses/veins. Risk factors were found in 73% of the patients, and most of the patients had a combination of 2 or more risk factors. The 30-day and 1-year mortality rates were 3% and 6%. CONCLUSIONS: The incidence of CVT in this population was higher than previously reported. The mortality rate was similar to previous studies.

Mitochondrial genome-wide association study of migraine - the HUNT Study.

BACKGROUND: Variation in mitochondrial DNA (mtDNA) has been indicated in migraine pathogenesis, but genetic studies to date have focused on candidate variants, with sparse findings. We aimed to perform the first mitochondrial genome-wide association study of migraine, examining both single variants and mitochondrial haplogroups. METHODS: In total, 71,860 participants from the population-based Nord-Trøndelag Health Study were genotyped. We excluded samples not passing quality control for nuclear genotypes, in addition to samples with low call rate and closely maternally related. We analysed 775 mitochondrial DNA variants in 4021 migraine cases and 14,288 headache-free controls, using logistic regression. In addition, we analysed 3831 cases and 13,584 controls who could be reliably assigned to a mitochondrial haplogroup. Lastly, we attempted to replicate previously reported mitochondrial DNA candidate variants. RESULTS: Neither of the mitochondrial variants or haplogroups were associated with migraine. In addition, none of the previously reported mtDNA candidate variants replicated in our data. CONCLUSIONS: Our findings do not support a major role of mitochondrial genetic variation in migraine pathophysiology, but a larger sample is needed to detect rare variants and future studies should also examine heteroplasmic variation, epigenetic changes and copy-number variation.

Effect of COVID-19 pandemic on stroke admission rates in a Norwegian population.

OBJECTIVES: There are concerns that public anxiety around COVID-19 discourages patients from seeking medical help. The aim of this study was to see how lockdown due to the pandemic affected the number of admissions of acute stroke. METHODS: All patients discharged from Akershus University Hospital with a diagnosis of transient ischemic attack (TIA) or acute stroke were identified by hospital chart review. January 3 to March 12 was defined as before, and March 13 to April 30 as during lockdown. RESULTS: There were 21.8 admissions/week before and 15.0 admissions/week during the lockdown (P < .01). Patients had on average higher NIHSS during the lockdown than before (5.9 vs. 4.2, P = .041). In the multivariable logistic regression model for ischemic stroke (adjusted for sex, age, living alone and NIHSS ≤ 5), there was an increased OR of 2.05 (95% CI 1.10-3.83, P = .024) for not reaching hospital within 4.5 hours during the lockdown as compared to the period before the lockdown. CONCLUSION: There was a significant reduction in number of admissions for stroke and TIAs during the lockdown due to the COVID-19 pandemic in Norway.