Functional characterization of a novel PRRT2 variant found in a Portuguese patient with hemiplegic migraine.

Familial hemiplegic migraine (FHM) is a rare autosomal-dominant form of migraine with aura. Three disease-causing genes have been identified for FHM: CACNA1A, ATP1A2 and SCN1A. However, not all families are linked to one of these three genes.PRRT2 variants were also commonly associated with HM symptoms; therefore, PRRT2 is hypothesized as the fourth gene causing FHM. PRRT2 plays an important role in neuronal migration, spinogenesis, and synapse mechanisms during development and calcium-dependent neurotransmitter release. We performed exome sequencing to unravel the genetic cause of migraine in one family, and a novel PRRT2 variant (c.938C > T;p.Ala313Val) was identified with further functional studies to confirm its pathogenicity. PRRT2-A313V reduced protein stability, led to protein premature degradation by the proteasome and altered the subcellular localization of PRRT2 from the plasma membrane (PM) to the cytoplasm. We identified and characterized for the first time in a Portuguese patient, a novel heterozygous missense variant in PRRT2 associated with HM symptoms. We suggest that PRRT2 should be included in the diagnosis of HM.

The epidemiology of multiple sclerosis in the entre Douro e Vouga region of northern Portugal: a multisource population-based study.

BACKGROUND: The prevalence of Multiple Sclerosis (MS) has been increasing worldwide and the north-south gradient of prevalence may be disappearing in the Northern hemisphere. The few previous prevalence studies performed in Portugal have reported a lower prevalence than the average for Western Europe. The aim of this study is to estimate the prevalence of MS in the Entre Douro e Vouga region, in Northern Portugal. METHODS: Multiple overlapping sources were used to ascertain all cases from the reference population: records from hospitals in the region and neighbouring regions; diagnostic databases of primary care physicians; and applications for disability benefits. The prevalence date was set at 1 January 2014. The reference population was 274,859 inhabitants. Patients' neurologists were contacted to retrieve clinical information and confirm the diagnosis based. RESULTS: A total of 177 patients were identified after eliminating duplicates from different sources. The female to male ratio was 1.9 and the mean age at disease onset was 33.5 (standard deviation: 10.3). Clinically isolated syndrome accounted for 9.0% of patients, relapsing remitting for 58.8%, secondary progressive for 20.3% and primary progressive for 11.8%. The prevalence was estimated in 64.4 patients per 100,000 (95% confidence interval: 54.9;73.9). CONCLUSIONS: In this study we report a higher point prevalence of MS than had been previously described in Portugal, but still far from the higher values recently reported in other Southern European countries.

Web-based cognitive training: patient adherence and intensity of treatment in an outpatient memory clinic.

BACKGROUND: Cognitive training has been playing an increasing role in the treatment of patients with cognitive deficits. This type of intervention, namely its intensity, can be optimized by incorporating information technology-based systems. OBJECTIVE: The intent of the study was to determine the treatment intensity and patient adherence to home-based cognitive training strategies (Web-based cognitive training). METHODS: A cohort of 45 patients with neurologic and psychiatric diseases attending an outpatient memory clinic (average age 50.7 years, SD 17.0; average education 7.8 years, SD 4.9) was followed over 18 months. Participants were challenged to use a Web-based cognitive training system, "COGWEB", on a daily basis, and fulfilled at least four weeks of training supervised remotely. Additionally, 11 patients attended face-to-face sessions. RESULTS: The average duration of continuous cognitive training was 18.8 weeks (SD 18.9). Each patient performed on average 363.5 minutes/week (SD 136.6). At 6-month follow-up, 82.8% complied with their treatment plan. The average proportion of complete weeks was 0.75 (SD 0.22). Patients with dementia trained more intensively (444.6 minutes/week), followed by patients with static brain lesion (414.5 minutes/week; P=.01). The group that held face-to-face sessions performed more training overall (481.4 vs 366.9 minutes/week), achieving a stronger expression and statistical significance in the last week of training (652.6 versus 354.9 minutes/week, P=.027). CONCLUSIONS: Overall, the weekly training intensity was high. Patients with dementia and static lesions performed more cognitive training. Face-to-face sessions were associated with higher intensities. The combination of classical methods with information technology systems seems to ensure greater training intensity.

Prognostic factors associated with disability in a cohort of neuromyelitis optica spectrum disorder and MOG-associated disease from a nationwide Portuguese registry.

INTRODUCTION: Neuromyelitis optica spectrum disorders (NMOSD) and MOG-associated disease (MOGAD) are an increasingly recognized group of demyelinating disorders of the central nervous system. Previous studies suggest that prognosis is predicted by older age at onset, number of relapses, the severity of the first attack and autoantibody status. OBJECTIVE: To study prognostic factors associated with disability progression and additional relapses in the 3-year follow-up of a national NMOSD/MOGAD cohort. RESULTS: Out of 180 of the initial Portuguese cohort, data on 82 patients was available at the end of the follow-up period (2019-2022). Two patients died. Twenty (24.4%) patients had one or more attack in this period (25 attacks in total), mostly transverse myelitis (TM) (56.0%) or optic neuritis (32.0%). MOGAD was significantly associated with a monophasic disease course (p = 0.03), with milder attacks (p = 0.01), while AQP4 + NMOSD was associated with relapses (p = 0.03). The most common treatment modalities were azathioprine (38.8%) and rituximab (18.8%). AQP4 + NMOSD more frequently required chronic immunosuppressive treatment, particularly rituximab (p = 0.01). Eighteen (22.5%) had an EDSS ≥6 at the end of the follow-up. AQP4 + NMOSD (p < 0.01) and the occurrence of transverse myelitis (TM) during disease (p = 0.04) correlated with an EDSS≥6 at the end of the follow-up period. MOGAD was significantly associated with an EDSS<6 (p < 0.01), and MOG+ cases that reached an EDSS>6 were significantly older (64.0 ± 2.8 versus 31.0 ± 17.1, p = 0.017). A bivariate logistic regression model including the serostatus and TM attacks during disease history successfully predicted 72.2% of patients that progressed to an EDSS≥6. CONCLUSION: This study highlights that myelitis predict increased disability (EDSS≥6) in NMOSD/MOGAG and AQP4 positivity is associated with increased disability.

Freeze the stroke: public awareness program for immediate detection of first symptoms.

BACKGROUND AND PURPOSE: The capacity of the general population to identify stroke signs is a major determinant for success of prehospital emergency pathways. Previous educational strategies using the media were usually short-lived and expensive. Tailoring information programs for special subgroups like acute stroke relatives may improve this situation. METHODS: A poster was assembled that included a list of stroke signs and instructions to call 911. Consecutive admissions to the stroke unit were randomized. Intervention consisted of an educational session with relatives, in which a nurse delivered 5 posters and asked for their placement on the freezer door at the kitchen of the patient's house and each of 4 neighboring houses. One month later, a questionnaire was administered to both groups. RESULTS: Sixty admissions were randomized (30 interventions), and 150 posters were distributed. One month after discharge, response rates were 81% for intervention group and 48% for control group. In the intervention arm, 64.5% had all the 4 answers correct, and 74.2% identified all first signs of stroke. For the control group, these values were 8% and 20%, respectively (P<0.001). CONCLUSIONS: This stroke unit-based information strategy improved awareness of relatives and neighbors when compared with the usual discharge plan. The program avoids the media and explores regional health care structure and family and social organizations, and it targets a subgroup keen to receive and spread information. The low cost, ease of use, and duration of the stimulus facilitate further testing and evaluation of impact on hospital presentation and thrombolytic treatment rates.

Ischemic vagus nuclei lesions and hyperglycemia: a study in 26 patients with lateral medullary infarction and matched controls.

BACKGROUND: Hyperglycemia is common after stroke in diabetic and nondiabetic patients. Furthermore, it has been associated with infarct expansion, worse functional outcomes and higher mortality. In a previous study, infarction of the insular region was related to higher poststroke glucose levels than infarcts in other cortical areas. Experimental studies in animal models suggested that the lower brainstem nuclei of the vagus nerve modulate insulin secretion. These nuclei are usually affected in lateral medullary infarction (LMI). We evaluated whether patients with lateral medullary stroke have worse poststroke glycemic control than other stroke patients. METHODS: A hospital-based stroke registry was used to identify 26 patients from the years 2000 to 2010 who fulfilled the following inclusion criteria: (1) a first-ever stroke; (2) neurological deficits compatible with LMI; (3) MRI confirmation of an ischemic lesion of the lateral medulla involving the vagus nerve nuclei, and (4) no simultaneous infarcts. Patients were excluded if they were admitted to the hospital more than 24 h after stroke onset or died in the first 24 h after hospital admission. A control group of other stroke patients was randomly selected from the same stroke registry and over the same time period, matching for the age and gender of the LMI group. The average glycemia was compared between the two groups using a linear regression model adjusted for confounders. Glycated hemoglobin at admission was used to estimate prestroke glycemic control. Prestroke glycemic averages were then compared with poststroke glycemia for the two groups using the Wilcoxon signed test for related samples. RESULTS: The average glycemia of the LMI patients in the first 24 h after stroke was 9.4 mmol/l (SD 3.2), and from 24 to 72 h it was 7.6 mmol/l (SD 2.8). In the comparison group, these values were 7.7 (SD 2.8) and 7.1 mmol/l (SD 2.7), respectively. As expected, diabetic patients had a significantly higher glycemia than nondiabetic patients (p < 0.0001). The adjusted linear regression model showed the average glycemia differences to be significant for the first 24 h (p = 0.001; R(2) = 55.6%) but not for the 24- 72 h period. The frequency of previous diabetes mellitus was similar in both groups. As compared to prestroke glycemic estimates, glycemia in lateral medullary stroke patients increased significantly more than in controls during the first 24 h after stroke (p = 0.01), but again there were no significant differences for the 24-72 h period. CONCLUSIONS: This study suggests that ischemic lesions of the vagus nerve nuclei are associated with worse early poststroke glycemic control than stroke in other locations. Confirmation of this hypothesis and the long-term implications of glucose control impairment warrant further prospective studies.

Late onset neuromyelitis optica spectrum disorders (LONMOSD) from a nationwide Portuguese study: Anti-AQP4 positive, anti-MOG positive and seronegative subgroups.

INTRODUCTION: Several neuroimmunological disorders have distinct phenotypes according to the age of onset, as in multiple sclerosis or myasthenia gravis. It is also described that late onset NMOSD (LONMOSD) has a different phenotype. OBJECTIVE: To describe the clinical/demographic characteristics of the LONMOSD and distinguish them from those with early onset (EONMOSD). METHODS: From a nationwide Portuguese NMOSD study we analyzed the clinical/demographic characteristics of the LONMOSD. RESULTS: From the 180 Portuguese patients 45 had disease onset after 50 years old, 80% were female. 23 had anti-AQP4 antibodies (51.1%), 13 anti-MOG antibodies (28.9%) and 9 were double seronegative (20.0%). The most common presenting phenotypes in LONMOSD were transverse myelitis (53.3%) and optic neuritis (26.7%), without difference from EONMOSD (p = 0.074). The mean EDSS for LONMOSD was 6.0 (SD=2.8), after a mean follow-up time of 4.58 (SD=4.47) years, which was significantly greater than the mean EDSS of EONMOSD (3.25, SD=1.80)(p = 0.022). Anti-AQP4 antibodies positive LONMOSD patients had increased disability compared to anti-MOG antibodies positive LONMOSD (p = 0.022). The survival analysis showed a reduced time to use a cane for LONMOSD, irrespective of serostatus (p<0.001). CONCLUSIONS: LONMOSD has increased disability and faster progression, despite no differences in the presenting clinical phenotype were seen in our cohort.

Fourier-Transform Infrared Spectroscopy as a Discriminatory Tool for Myotonic Dystrophy Type 1 Metabolism: A Pilot Study.

Myotonic dystrophy type 1 (DM1) is a hereditary disease characterized by progressive distal muscle weakness and myotonia. Patients with DM1 have abnormal lipid metabolism and a high propensity to develop a metabolic syndrome in comparison to the general population. It follows that metabolome evaluation in these patients is crucial and may contribute to a better characterization and discrimination between DM1 disease phenotypes and severities. Several experimental approaches are possible to carry out such an analysis; among them is Fourier-transform infrared spectroscopy (FTIR) which evaluates metabolic profiles by categorizing samples through their biochemical composition. In this study, FTIR spectra were acquired and analyzed using multivariate analysis (Principal Component Analysis) using skin DM1 patient-derived fibroblasts and controls. The results obtained showed a clear discrimination between both DM1-derived fibroblasts with different CTG repeat length and with the age of disease onset; this was evident given the distinct metabolic profiles obtained for the two groups. Discrimination could be attributed mainly to the altered lipid metabolism and proteins in the 1800-1500 cm-1 region. These results suggest that FTIR spectroscopy is a valuable tool to discriminate both DM1-derived fibroblasts with different CTG length and age of onset and to study the metabolomic profile of patients with DM1.

Neuromyelitis optica spectrum disorders: A nationwide Portuguese clinical epidemiological study.

INTRODUCTION: Neuromyelitis optica spectrum disorder (NMOSD) is a rare disorder in which astrocyte damage and/or demyelination often cause severe neurological deficits. OBJECTIVE: To identify Portuguese patients with NMOSD and assess their epidemiological/clinical characteristics. METHODS: This was a nationwide multicenter study. Twenty-four Portuguese adult and 3 neuropediatric centers following NMOSD patients were included. RESULTS: A total of 180 patients met the 2015 Wingerchuk NMOSD criteria, 77 were AQP4-antibody positive (Abs+), 67 MOG-Abs+, and 36 seronegative. Point prevalence on December 31, 2018 was 1.71/100,000 for NMOSD, 0.71/100,000 for AQP4-Abs+, 0.65/100,000 for MOG-Abs+, and 0.35/100,000 for seronegative NMOSD. A total of 44 new NMOSD cases were identified during the two-year study period (11 AQP4-Abs+, 27 MOG-Abs+, and 6 seronegative). The annual incidence rate in that period was 0.21/100,000 person-years for NMOSD, 0.05/100,000 for AQP4-Abs+, 0.13/100,000 for MOG-Abs+, and 0.03/100,000 for seronegative NMOSD. AQP4-Abs+ predominated in females and was associated with autoimmune disorders. Frequently presented with myelitis. Area postrema syndrome was exclusive of this subtype, and associated with higher morbidity/mortality than other forms of NMOSD. MOG-Ab+ more often presented with optic neuritis, required less immunosuppression, and had better outcome. CONCLUSION: Epidemiological/clinical NMOSD profiles in the Portuguese population are similar to other European countries.

Development of a self-administered web-based test for longitudinal cognitive assessment.

Sequential testing with brief cognitive tools has been recommended to improve cognitive screening and monitoring, however the few available tools still depend on an external evaluator and periodic visits. We developed a self-administered computerized test intended for longitudinal cognitive testing (Brain on Track). The test can be performed from a home computer and is composed of several subtests, expected to evaluate different cognitive domains, all including random elements to minimize learning effects. An initial (A) and a refined version of the test (B) were applied to patients with mild cognitive impairment or early dementia (n = 88) and age and education-matched controls. A subsample of a population-based cohort (n = 113) performed the test at home every three months to evaluate test-retest reliability. The test's final version Cronbach's alpha was 0.90, test scores were significantly different between patients and controls (p = 0.001), the area under the receiver operating characteristic curve was 0.75 and the smallest real difference (43.04) was lower than the clinical relevant difference (56.82). In the test-retest reliability analysis 9/10 subtests showed two-way mixed single intraclass consistency correlation coefficient >0.70. These results imply good internal consistency, discriminative ability and reliability when performed at home, encouraging further longitudinal clinical and population-based studies.

Implementation and Outcomes of a Collaborative Multi-Center Network Aimed at Web-Based Cognitive Training - COGWEB Network.

BACKGROUND: Cognitive care for the most prevalent neurologic and psychiatric conditions will only improve through the implementation of new sustainable approaches. Innovative cognitive training methodologies and collaborative professional networks are necessary evolutions in the mental health sector. OBJECTIVE: The objective of the study was to describe the implementation process and early outcomes of a nationwide multi-organizational network supported on a Web-based cognitive training system (COGWEB). METHODS: The setting for network implementation was the Portuguese mental health system and the hospital-, academic-, community-based institutions and professionals providing cognitive training. The network started in August 2012, with 16 centers, and was monitored until September 2013 (inclusions were open). After onsite training, all were allowed to use COGWEB in their clinical or research activities. For supervision and maintenance were implemented newsletters, questionnaires, visits and webinars. The following outcomes were prospectively measured: (1) number, (2) type, (3) time to start, and (4) activity state of centers; age, gender, level of education, and medical diagnosis of patients enrolled. RESULTS: The network included 68 professionals from 41 centers, (33/41) 80% clinical, (8/41) 19% nonclinical. A total of 298 patients received cognitive training; 45.3% (n=135) female, mean age 54.4 years (SD 18.7), mean educational level 9.8 years (SD 4.8). The number enrolled each month increased significantly (r=0.6; P=.031). At 12 months, 205 remained on treatment. The major causes of cognitive impairment were: (1) neurodegenerative (115/298, 38.6%), (2) structural brain lesions (63/298, 21.1%), (3) autoimmune (40/298, 13.4%), (4) schizophrenia (30/298, 10.1%), and (5) others (50/298, 16.8%). The comparison of the patient profiles, promoter versus all other clinical centers, showed significant increases in the diversity of causes and spectrums of ages and education. CONCLUSIONS: Over its first year, there was a major increase in the number of new centers and professionals, as well as of the clinical diversity of patients treated. The consolidation of such a national collaborative network represents an innovative step in mental health care evolution. Furthermore, it may contribute to translational processes in the field of cognitive training and reduce disease burden.

Spasticity as the first manifestation of ischaemic lesions involving the cingulum.

Background and Purpose. Spasticity is a positive sign of upper motor neuron syndrome that usually develops weeks after a stroke. The mechanisms that lead to its appearance are not completely understood, namely, the cortical regions whose lesion may induce spasticity. Summary of Cases. We report two patients with an ischaemic stroke entailing the anterior cingulate gyrus (pericallosal artery territory), who presented with acute hemiplegia and spasticity since symptom onset. Spasticity resolved within days after onset. Conclusions. The acute destruction of the anterior cingulate region, interrupting inhibitory projections towards lower motor centres, probably explains the acute onset of spasticity that occurred in these two patients. Further studies addressing the role of this region in acute and chronic disturbances of muscular tone are necessary.

A rehabilitation tool designed for intensive web-based cognitive training: description and usability study.

BACKGROUND: Cognitive deficits are among the most disabling of neurological diseases and have a serious impact on the quality of life of patients and families. Cognitive training has been proven successful in improving or compensating for neuropsychological deficits after acute brain injury, but its efficacy highly depends on the intensity of treatment over an extended period of time. Therefore, cognitive training indicates expensive human resources and renders the rehabilitation process vulnerable to physical and economic barriers for the majority of patients. OBJECTIVE: The aim of this study was to develop and test a new Web-based rehabilitation tool that provides intensive cognitive training at home under clinical prescription and monitoring, at affordable costs. METHODS: From a pool of 60 original exercises, designed and used over the past 10 years for cognitive training at our center, we developed 27 exercises on a computer game format, with automatic increase or decrease of difficulty levels. These exercises were assembled in a clean, user-friendly design and covered various cognitive domains such as attention (n=4), memory (n=11), language (n=3), calculus (n=3), praxis (n=2), and executive functions (n=3). A Web 2.0 platform was also designed to provide medical prescription of cognitive training sessions, performed at the patient's home. These sessions included continuous monitoring of compliance, performance, and evolution; algorithms for automatic adjustment and long-term learning through use, and database recording of all activities. The end-user interaction test included 80 patients from our memory clinic from several groups including subjective memory complaints (n=20), traumatic brain injury (n=20), stroke and other static brain lesions (n=20), and mild Alzheimer's disease (n=20). During a 1-hour session, patients and their relatives were taught to use the system and allowed to practice using it. At the end of the session, they were asked to complete a questionnaire. RESULTS: A total of 48/80 patients (60%) attended the training session. The mean age of the patients was 60 years (SD 13.3, range 41-78), and the mean level of formal education was 6 years (range 4-16). Of all the participants, 32/48 patients (66%) have previously used a computer. All patients and their relatives made a positive evaluation of the cognitive training tool. Only 2/48 patients (4%) were not interested in performing the exercises at home; 19/48 patients (39%) mentioned the need for further coaching from a relative or health care professional. The patients who mentioned difficulties in performing the exercises have not used the computer earlier. CONCLUSIONS: This new Web-based system was very well accepted by patients and their relatives, who showed high levels of motivation to use it on a daily basis at home. The simplicity of its use and comfort were especially outlined. This tool will have an important effect on human resource management, in increasing the patient access to specialized health care and improving the quality and national health system costs of rehabilitation programs.

Cerebellar ataxia, hemiplegic migraine, and related phenotypes due to a CACNA1A missense mutation: 12-year follow-up of a large Portuguese family.

OBJECTIVE: To document and discuss the broad phenotypic variability in a Portuguese family with cerebellar ataxia, hemiplegic migraine, and related syndromes caused by missense mutation c.1748 (p.R583Q) in the CACNA1A gene. DESIGN: Observational 12-year follow-up study. SETTING: Community and hospital care. PATIENTS: Sixteen patients in a 4-generation family were identified in 1998 in a population-based survey. The follow-up revealed 28 patients (25 of whom were observed) and 32 unaffected relatives with an a priori risk of 50%. RESULTS: Four major phenotypes (migraine with multiple auras, transient focal neurological deficits without headache, coma triggered by minor head trauma, and slowly progressive cerebellar ataxia) were present in various combinations. The initial manifestation was ataxia in 16 patients and a transient episode in 12 patients. Eighteen patients did not have migraine, and 11 showed only ataxia. The c.1748 (p.R583Q) mutation in CACNA1A was confirmed in all 23 of the patients who were tested but was not found in any of the 27 adult relatives. The CACNA1A CAG repeat expansion was excluded. CONCLUSIONS: A unique missense mutation in the CACNA1A gene, which exhibits a very high penetrance and expressivity, may present a phenotypic spectrum that is broader than current descriptions. Single-gene disorders can behave as complex traits, which reinforces the importance of genetic modifiers in the tightly regulated function of P/Q-type calcium channels. The clinical spectrum of missense mutation CACNA1A -related disorders is much broader than strictly familial hemiplegic migraine.