Epilepsy and Multiple Sclerosis in Sicily: A Population-based Study

Common comorbid and secondary conditions leading to hospitalization in multiple sclerosis patients in the United States

OBJECTIVE

To identify the burden of hospitalization and common primary admitting diagnoses among MS patients in the United States (US).

BACKGROUND

The burden of hospitalizations and conditions leading to hospitalizations in MS patients in the US has not been well described.

DESIGN/METHODS

Using the Nationwide Inpatient Sample for 2001-2010, all patients with principal or secondary diagnosis of MS were identified, and the principal admitting diagnoses were compared with that of non-MS patients. Trends in hospitalizations were studied in specific age groups (1-9 yrs, 10-19 yrs, 20-29 yrs, 30-39 yrs, 40-49 yrs, 50-59 yrs, 60-69 yrs,70-79 yrs, 80-84 yrs and ≥85 yrs), and population level rates were obtained and compared with non-MS patients to obtain rate ratios (RR) and odds ratios (OR).

RESULTS

A total of 1,240,410 MS patients were identified representing 4 out of every 1000 US hospital admissions, with an estimated female/male ratio of 2.72/1. The median age for MS hospitalizations was 53 years (Interquartile range=18). The majority of all MS hospitalizations occurred in the 30-69-year age bracket (82.17 %). The average length of in-patient hospital stays for MS patients compared to the non-MS population was 5.8 vs. 4.5 days (p < 0.001), and more MS patients had Medicare insurance (50.36 % vs. 42.24 %, p < 0.001). Overall, conditions such as urinary tract infections (UTI) - (RR11.43, p < 0.001), septicemia (RR8.53, p < 0.001), pneumonia (RR2.84, p < 0.001), chronic skin ulcers (RR20.64, p < 0.001), and lower limb and femoral neck fractures (RR2.86, p < 0.001) were present with increased frequency among MS patients. Patterns of comorbidity varied markedly by age group. The estimated average annual in-hospital charges adjusted to 2010 dollars for all MS inpatient hospitalizations was 3 billion U.S. dollars.

CONCLUSIONS

Patients with MS are admitted into hospital at a younger age, are hospitalized longer and consume more Medicare resources than the similar patients without MS in the general population. Infections account for a large proportion of MS-associated hospitalizations, from young adulthood onward. These findings are particularly significant in light of the increasing availability of disease modifying therapies with more potent immunosuppressive properties, as well as the accumulating data that systemic infection can drive MS relapses.

Multiple Sclerosis and Autoimmune Comorbidities

Multiple sclerosis (MS) is a chronic inflammatory and neurodegenerative disease of the central nervous system characterized by broad inter- and intraindividual heterogeneity and different prognoses. Multisystem comorbidities are frequent features in people with MS (PwMS) and can affect treatment choices, quality of life, disability and mortality. In this scenario, autoimmune comorbidities play a cardinal role for several reasons, such as the implication on MS pathogenesis, diagnostic delay, disease activity, disability progression, brain atrophy, and treatment choice. However, the impact of an autoimmune comorbid condition on MS is not fully elucidated. This review aims to summarize the currently available data on the incidence and prevalence of autoimmune diseases in PwMS, the possible effect of this association on clinical and neuroradiological MS course and its impact on treatment choice.

Multiple sclerosis is associated with higher comorbidity and health care resource use: A population-based, case-control study in a western Mediterranean region

BACKGROUND AND PURPOSE

Comorbidities are common in multiple sclerosis (MS), and have been associated with worse outcomes and increased health care resource usage. We studied the frequency of comorbidities and adverse health behaviors (AHBs) in MS patients in the Mediterranean region of Catalonia.

METHODS

This population-based, case-control study used primary health care information covering 80% of Catalonia's population. Cases were matched by age/sex with randomly chosen controls (ratio = 1:5). Demographic information, comorbidities, AHBs, annual visits, sick leave days, and medication dispensing were studied. The association of comorbidities with MS and the profile of comorbidities according to sex within MS cases were assessed with multivariate logistic regression models, after adjusting for confounding variables. Health care resource usage was analyzed in MS cases compared to controls, and within MS cases in those with compared to those without comorbidities.

RESULTS

Five thousand five hundred forty-eight MS cases and 27,710 controls (70% female, mean age = 48.3 years) were included. Stroke (odds ratio [OR] = 1.54, 95% confidence interval [CI] = 1.17-1.99), epilepsy (OR = 2.46, 95% CI = 1.94-3.10), bipolar disorder (OR = 1.67, 95% CI = 1.17-2.36), and depression (OR = 1.83, 95% CI = 1.70-1.98) were more frequent in MS. Cases were more prone to smoking but less to alcohol intake. Among cases, psychiatric comorbidities were more frequent in women, whereas cardiovascular diseases and AHBs were more frequent in men. MS patients, particularly with comorbidities, had higher health care resource usage than controls.

CONCLUSIONS

Psychiatric comorbidities, stroke, epilepsy, and AHBs are more common in MS patients than in the general population in the western Mediterranean region of Catalonia. The presence of comorbidities increases the health care resource usage in MS patients.

Prevalence of Seizure/Epilepsy in Patients with Multiple Sclerosis: A Systematic Review and Meta-Analysis

Background

Seizure and epilepsy are among the initial symptoms of multiple sclerosis (MS), yet different prevalence rates are reported for them in the previous studies. The goal of this systematic review is to estimate the pooled prevalence of seizure and epilepsy in patients with MS.

Methods

We searched PubMed, Scopus, EMBASE, Web of Science, google scholar, and gray literature including references from identified studies and conference abstracts published up to October 2019. The search strategy included the MeSH terms and text words as ((Epilepsies OR Seizure Disorder OR Seizure Disorders OR Awakening Epilepsy OR Epilepsy, Awakening OR Epilepsy, Cryptogenic OR Cryptogenic Epilepsies OR Cryptogenic Epilepsy OR Epilepsies, Cryptogenic OR epilepsy OR seizure) AND (Multiple Sclerosis OR Sclerosis, Multiple) OR Sclerosis, Disseminated) OR Disseminated Sclerosis) OR MS (Multiple Sclerosis)) OR Multiple Sclerosis, Acute Fulminating).

Results

The literature review resulted in 4860 articles; 2593 articles remained after eliminating the duplicates. For the final analysis, 39 articles were included, 9 of which were conference abstracts. The pooled prevalence of seizure in MS cases was 2%, 95% confidence interval (CI)(1%-3%) (I² = 91.8%, P < 0.001). The pooled prevalence of epilepsy in MS cases was 3%, 95% CI (2%-4%) (I2 = 92.9%, P < 0.001). The pooled prevalence of epilepsy in Asia, Europe, and America was 6%, 3%, and 3%, respectively. The level of heterogeneity decreased after subgroup analysis in Asian and American subgroups. Meta-regression analysis showed continent is not a source of heterogeneity (coefficient = -0.007, P = 0.6).

Conclusions

The result of this systematic review shows that the pooled prevalence of seizure and epilepsy among MS patients is 2% and 3%, respectively.

Patients With Epileptic Seizures and Multiple Sclerosis in a Multiple Sclerosis Center in Southern Germany Between 2003-2015

Background: So far, many studies have shown that the risk of developing seizures and epilepsy is higher among patients with multiple sclerosis (MS) than in the general population. However, the causal link between these two diseases is still unclear. In addition, it is not clearly understood whether and to what extent the manifestation of seizures and epilepsy in patients with MS affects the clinical course and the long-term prognosis of the disease. We aimed to retrospectively identify and describe patients with MS and with seizures and epilepsy which were seen at the Department of Neurology of the University of Regensburg in Germany between the years 2003-2015. Methods: With the help of the electronic documentation system of hospital admitted patients followed by scrutinizing medical records of patients with MS for evidence of seizures and epilepsy, we identified patients with MS and seizures or epilepsy. Results: We identified 22 individuals (1.74%) out of 1,267 patients with MS with seizures or epilepsy. 18 of these 22 individuals met criteria for epilepsy (1.42%). Nine MS patients (40.9%) suffered from relapsing-remitting MS (RRMS) whereas 11 MS patients (50.0%) showed a secondary progressive disease course (SPMS). Five of those (45.5%) converted from RRMS to SPMS before they acquired epilepsy. None of the identified patients with MS and seizures or epilepsy suffered from primary progressive MS (PPMS). Moreover, two MS patients (9.1%) had a history of seizures before MS onset. Seizures were of focal onset in 17 patients with MS (77.3%). Fourteen out of these 17 MS patients presented with focal to bilateral tonic-clonic seizures (82.4%). Five MS patients (22.7%) showed tonic clonic seizures of unknown onset. Status epilepticus was reported in three patients with MS (13%), for one patient the data was inconclusive. Conclusion: The occurrence of seizures and epilepsy was higher than in the general population, suggesting a causal relationship between both diseases. In most cases, seizures occurred after the first manifestation of MS. The high frequency of focal seizures supports the concept of cerebral lesions in patients with MS playing an important role in precipitation of seizures and epilepsy.

Epilepsy and associated mortality in patients with multiple sclerosis

BACKGROUND AND PURPOSE

We aimed to determine the prevalence of epilepsy in patients with multiple sclerosis (MS) at diagnosis, the risk of developing epilepsy after the diagnosis of MS and the relative risk of mortality associated with epilepsy.

METHODS

We used the UK Clinical Practice Research Data-link to identify 2526 patients with incident MS and 9980 age-, sex- and index year-matched non-MS controls from 1997 to 2006. Logistic regression was used to estimate odds ratios [95% confidence interval (CI)] for epilepsy and Cox regression was used to estimate hazard ratios (HRs) (95% CI) for epilepsy and mortality.

RESULTS

Patients with incident MS were on average 45 years old and 70.9% were female. At diagnosis, the prevalence of epilepsy in patients with MS was 1.30% compared with 0.57% in non-MS controls. At diagnosis, MS was associated with an adjusted odds ratio (95% CI) of 2.11 (1.36-3.27) for pre-existing epilepsy. Among epilepsy-free patients, the cumulative probabilities of developing epilepsy, first recorded within 10 years of the index date, were 2.77% for patients with MS and 0.90% for controls. MS was associated with an adjusted HR (95% CI) of 6.01 (2.94-12.29) for epilepsy. Among patients with MS, epilepsy was associated with an HR (95% CI) of 2.23 (1.02-4.84) for all-cause mortality.

CONCLUSIONS

This population-based study found an increased prevalence of epilepsy in patients with MS at diagnosis when compared with non-MS controls and the risk of developing epilepsy was also higher following the MS diagnosis. Patients with MS with epilepsy had a higher risk of mortality compared with those without.

Status Epilepticus and Multiple Sclerosis: A Case Presentation and Literature Review

PURPOSE

To search the literature for the frequency, pathogenesis, prognosis, and treatment of seizures and status epilepticus (SE) in patients with multiple sclerosis (MS).

METHODS

We report 2 patients with MS who presented with SE and review the literature.

RESULTS

Seizures and SE episodes worsened during MS relapses in the first patient. SE episodes and MS relapses significantly decreased after initiation of natalizumab treatment but she still had seizures and was taking 4 antiepileptic drugs (AEDs). The second patient had super refractory SE and was treated with AEDs and coma induction; SE was controlled in 1 week. Antibodies against glycine receptors were reported in her serum after her death.

CONCLUSION

SE has been reported to remain refractory to conventional AEDs, and improve with treatment of MS relapse. Seizures often occur during MS relapses, and might be the presenting symptom of MS or the only symptom of a relapse. Patients with MS and epilepsy have been reported to have more severe MS disease courses. Seizures are refractory to treatment in patients with MS with chronic epilepsy; however, prognosis is quite good in patients experiencing provoked seizures during an MS relapse. Since some EEG findings may have prognostic value, their evaluation is invaluable for the determination of outcome. No treatment guidelines have been specified for patients with MS and SE. However, treatment with AEDs, ideally new-generation AEDs, and an MS treatment review with a new protocol will ensure a fast response to the improvement of SE.

Temporal lobe cortical pathology and inhibitory GABA interneuron cell loss are associated with seizures in multiple sclerosis

BACKGROUND

Seizures are recognised in multiple sclerosis (MS), but their true incidence and the mechanism by which they are associated with MS is unclear.

OBJECTIVE

The objective of this paper is to determine the lifetime frequency of seizures in the United Kingdom MS Tissue Bank (UKMSTB) population and any pathological features associated with seizures.

METHODS

We evaluated 255 individuals from the UKMSTB. A subset underwent analysis of cortical thickness, grey matter lesion (GML) (type and number) and cortical neuronal numbers (total and GABAergic).

RESULTS

A total of 37/255 patients had seizures (14.5% lifetime incidence); in 47% they were associated with concurrent infection. In those with seizures, death and wheelchair use occurred earlier and in 59% seizures developed after 15 years of disease. Seizures were associated with Type 1 GMLs and reduced cortical thickness in the middle temporal gyrus. Localised selective GABAergic interneuron loss in layers IV and VI was related to GMLs but was not explained by the presence of inflammation or by mitochondrial dysfunction within Type I GMLs.

CONCLUSION

We confirm that seizure frequency rises in MS. Type I GMLs in the temporal lobe underlie a loss of inhibitory interneurons in cortical layers IV and VI and these changes could together with concurrent infection enhance susceptibility to seizures.

Safety profile of dalfampridine extended release in multiple sclerosis: 5-year postmarketing experience in the United States

BACKGROUND

Dalfampridine extended release tablets (dalfampridine-ER; prolonged-, modified, or sustained-release fampridine outside the US), 10 mg twice daily, was approved by the US Food and Drug Administration (FDA) in January 2010 to improve walking in people with multiple sclerosis, as determined by an increase in walking speed.

OBJECTIVE

To provide a descriptive analysis of reported adverse events (AEs) for commercially available dalfampridine-ER from March 2010 through March 31, 2015.

METHODS

Five-year postmarketing data for dalfampridine-ER were available from the exposure of approximately 107,000 patients in the US (103,700 patient-years). Commonly reported AEs (≥2% of all reported AEs) and serious AEs were determined. The incidence of reported seizures was determined and the events were further investigated.

RESULTS

Among the 107,000 patients exposed to dalfampridine-ER (70% female; mean age 52.1), the most common AEs were dizziness (3.7%), insomnia (3.2%), balance disorder (3%), fall (2.4%), headache (2.4%), nausea (2.1%), and urinary tract infection (2%). Other common AEs were drug ineffectiveness (5.8%), gait disturbance (4.6%), and inappropriate dosing (3.1%). Serious AEs included rare anaphylactic reactions (five cases) and drug hypersensitivity reactions (eight cases). A total of 657 seizure cases were reported (6.3/1,000 patient-years); of these, 324 were medically confirmed (3.1/1,000 patient-years). Incidence of reported seizures was stable over time. Duration of treatment prior to a seizure ranged from a single dose to >4 years; 12% of the seizures occurred within a week of starting treatment.

CONCLUSION

The 5-year US postmarketing safety data of dalfampridine-ER is consistent with the safety profile observed in clinical trials. Incidence of reported seizures remained stable over time. Since commercial availability in March 2010, a warning regarding the risk of anaphylaxis and severe allergic reactions was added to the US prescribing information.

A systematic review of the incidence and prevalence of comorbidity in multiple sclerosis: overview

Background:

Comorbidity is an area of increasing interest in multiple sclerosis (MS).

Objective:

The objective of this review is to estimate the incidence and prevalence of comorbidity in people with MS and assess the quality of included studies.

Methods:

We searched the PubMed, SCOPUS, EMBASE and Web of Knowledge databases, conference proceedings, and reference lists of retrieved articles. Two reviewers independently screened abstracts. One reviewer abstracted data using a standardized form and the abstraction was verified by a second reviewer. We assessed study quality using a standardized approach. We quantitatively assessed population-based studies using the I² statistic, and conducted random-effects meta-analyses.

Results:

We included 249 articles. Study designs were variable with respect to source populations, case definitions, methods of ascertainment and approaches to reporting findings. Prevalence was reported more frequently than incidence; estimates for prevalence and incidence varied substantially for all conditions. Heterogeneity was high.

Conclusion:

This review highlights substantial gaps in the epidemiological knowledge of comorbidity in MS worldwide. Little is known about comorbidity in Central or South America, Asia or Africa. Findings in North America and Europe are inconsistent. Future studies should report age-, sex- and ethnicity-specific estimates of incidence and prevalence, and standardize findings to a common population.

A systematic review of the incidence and prevalence of sleep disorders and seizure disorders in multiple sclerosis

Background:

Several studies have suggested that comorbid neurologic disorders are more common than expected in multiple sclerosis (MS).

Objective:

To estimate the incidence and prevalence of comorbid seizure disorders and sleep disorders in persons with MS and to evaluate the quality of studies included.

Methods:

The PUBMED, EMBASE, Web of Knowledge, and SCOPUS databases, conference proceedings, and reference lists of retrieved articles were searched. Two reviewers independently screened abstracts to identify relevant articles, followed by full-text review of selected articles. We assessed included studies qualitatively and quantitatively (I² statistic), and conducted meta-analyses among population-based studies.

Results:

We reviewed 32 studies regarding seizure disorders. Among population-based studies the incidence of seizure disorders was 2.28% (95% CI: 1.11–3.44%), while the prevalence was 3.09% (95% CI: 2.01–4.16%). For sleep disorders we evaluated 18 studies; none were population-based. The prevalence ranged from 0–1.6% for narcolepsy, 14.4–57.5% for restless legs syndrome, 2.22–3.2% for REM behavior disorder, and 7.14–58.1% for obstructive sleep apnea.

Conclusion:

This review suggests that seizure disorders and sleep disorders are common in MS, but highlights gaps in the epidemiological knowledge of these conditions in MS worldwide. Other than central-western Europe and North America, most regions are understudied.

Multiple sclerosis and seizures: incidence and prevalence over 40 years

OBJECTIVES

The prevalence of multiple sclerosis (MS) is increasing worldwide. Epileptic seizures are more common in MS patients than in the general population. The aim of this study was to investigate changes in the prevalence and incidence of MS in a well-defined population over several decades and estimate the occurrence of epilepsy in the same cohort.

MATERIALS AND METHODS

Patients diagnosed with MS in the County of Vestfold, Norway in the period of 1983-2003 were identified. Point prevalence for MS and epilepsy was calculated for January 1, 2003. The average annual incidence rates were calculated in five-year periods from 1983 to 2002. These numbers were compared to previously published figures of prevalence from 1963 and incidence from 1953.

RESULTS

On prevalence day, we identified 364 patients diagnosed with MS living in Vestfold. Thus, the prevalence increased from 61.6/100,000 in 1963 to 166.8/100,000 in 2003. In the period 1983-2002, the annual incidence fluctuated between 4.2 and 7.3/100,000/year (mean 4.5, 95% CI 3.6 - 5.5). In 2003, the portion of MS patients with epileptic seizures was 7.4%, compared to 2.9% in 1963.

CONCLUSIONS

During the 40 years follow-up of this population, the incidence of MS was stable, while the prevalence of MS and the share of MS patients with epileptic seizures increased. Compared to the general population, the risk of having active epilepsy was increased fourfold. We assume that this is a consequence of an increased survival in MS patients.

Association between multiple sclerosis and epilepsy: large population-based record-linkage studies

BACKGROUND

Multiple sclerosis (MS) and epilepsy are both fairly common and it follows that they may sometimes occur together in the same people by chance. We sought to determine whether hospitalisation for MS and hospitalisation for epilepsy occur together more often than expected by chance alone.

METHODS

We analysed two datasets of linked statistical hospital admission records covering the Oxford Record Linkage Study area (ORLS, 1963-1998) and all England (1999-2011). In each, we calculated the rate of occurrence of hospital admission for epilepsy in people after admission for MS, compared with equivalent rates in a control cohort, and expressed the results as a relative risk (RR).

RESULTS

The RR for hospital admission for epilepsy following an admission for MS was significantly high at 4.1 (95% confidence interval 3.1-5.3) in the ORLS and 3.3 (95% CI 3.1-3.4) in the all-England cohort. The RR for a first recorded admission for epilepsy 10 years and more after first recorded admission for MS was 4.7 (2.8-7.3) in ORLS and 3.9 (3.1-4.9) in the national cohort. The RR for the converse-MS following hospitalisation for epilepsy-was 2.5 (95% CI 1.7-3.5) in the ORLS and 1.9 (95% CI 1.8-2.1) in the English dataset.

CONCLUSIONS

MS and epilepsy occur together more commonly than by chance. One possible explanation is that an MS lesion acts as a focus of an epileptic seizure; but other possibilities are discussed. Clinicians should be aware of the risk of epilepsy in people with MS. The findings may also suggest clues for researchers in developing hypotheses about underlying mechanisms for the two conditions.

Dalfampridine extended release tablets: 1 year of postmarketing safety experience in the US

BACKGROUND

Dalfampridine extended release tablets (dalfampridine-ER; prolonged-, modified, or sustained-release fampridine in some countries) were approved in the US to improve walking in patients with multiple sclerosis, as demonstrated by improvement in walking speed. Postmarketing safety experience is available from exposure of approximately 46,000 patients in the US from product approval through March 2011.

OBJECTIVE

To provide a descriptive analysis of all spontaneously reported postmarketing adverse events (AEs) for dalfampridine-ER since product launch.

METHODS

AE data were extracted from the safety database from product launch through March 31, 2011; AEs were classified using the Medical Dictionary for Regulatory Activities. Seizure cases were reviewed for patient demographics, time to event from treatment onset, and presence of additional risk factors.

RESULTS

THE MOST FREQUENTLY REPORTED POSTMARKETING AES WERE SIMILAR TO THOSE REPORTED DURING CLINICAL DEVELOPMENT: dizziness, insomnia, balance disorder, headache, nausea, urinary tract infection, asthenia, and back pain (all included in US product labeling). New clinically significant findings are related to lack of efficacy and inappropriate dosing. Of the approximately 46,000 patients exposed, 85 seizures were reported (∼5.4/1000 patient-years), of which 82 were reported or confirmed by a health care practitioner (∼5.2/1000 patient-years). Beyond the intrinsic multiple sclerosis-related seizure risk, more than half of the 85 cases (62%) had an additional potential risk factor for seizure including a previous history of convulsions, renal impairment, incorrect dosing, or use of concurrent medications with a labeled seizure risk. Duration of treatment prior to the seizure ranged from one dose to 365 days; 26/85 (31%) patients suffered a seizure within a week of starting treatment.

CONCLUSION

Spontaneous safety data from the US postmarketing experience were consistent with the safety profile seen during clinical development. Although first-year seizure incidence was not substantially different from that observed in dalfampridine-ER clinical trials, patients should be monitored for concomitant use of drugs that lower seizure threshold.

Epileptic seizures in Japanese patients with multiple sclerosis and neuromyelitis optica

PURPOSE

To examine the incidence and clinical features of epileptic seizures in Japanese patients with multiple sclerosis (MS) and neuromyelitis optica (NMO).

METHODS

We reviewed medical records of all patients who visited the Neurology Clinic in Utano National Hospital between January and December, 2009, and enrolled 63 MS patients who fulfilled the McDonald criteria (2005) (mean age, 41.1 years) and 31 NMO patients who fulfilled the Wingerchuk criteria (2006) (mean age, 44.6 years). Patients with a history of epileptic seizures were selected and their clinical features were obtained.

RESULTS

Four MS patients (6.3%; 2 men and 2 women; mean age, 32.5 years) and 4 NMO patients (12.9%; 4 women; mean age, 36.0 years) had epileptic seizures. Disease onset age of MS patients with seizures was significantly younger than those without seizures by 13.1 years, and Expanded Disability Status Scale of NMO patient with seizures was significantly higher than those without seizures by 2.2. All 8 patients showed brain lesions on magnetic resonance imaging and 2 MS patients had tumefactive demyelinating lesions. Electroencephalography showed interictal epileptiform discharges in 5 patients. Seizure types of 6 patients were recognized as partial seizures based on clinical semiology. All patients responded to antiepileptic therapy well. In both MS and NMO, there were both seizures with and without concurrent relapse.

CONCLUSIONS

Similar to MS, NMO patients possibly have higher risk to develop epileptic seizures than general population.

Walking impairment in patients with multiple sclerosis - a new therapeutic approach and clinical potential of dalfampridine extended release tablets

Walking impairment is a clinical hallmark of multiple sclerosis (MS) that has been under-recognized as a therapeutic target for pharmacologic intervention. The development and approval of dalfampridine extended release tablets (dalfampridine-ER; known as prolonged-, modified, or sustained-release fampridine outside the USA), 10 mg taken twice daily, to improve walking in patients with MS, fills a previously unmet need. In three randomized, double-blind, placebo-controlled trials, dalfampridine-ER improved walking speed in approximately one-third (37%) of treated patients, and average walking speed on therapy among these responders improved by approximately 25% relative to baseline. Walking-speed improvement among responders was clinically significant, as determined by a statistically significant improvement in the patient-reported 12-item Multiple Sclerosis Walking Scale. Long-term extension studies indicate that responders were able to maintain benefits, compared with nonresponders over prolonged periods of treatment. Dalfampridine-ER was generally well tolerated. Dizziness, insomnia, balance disorder, headache, nausea, urinary tract infection, and asthenia were the most common adverse events. Although the incidence of seizures appeared to be dose related, among patients treated with dalfampridine-ER in the three trials, the rate of seizures was 0.25%. These efficacy and safety data suggest that dalfampridine-ER can be a useful and clinically relevant addition to the pharmacologic armamentarium for the management of MS symptoms and disabilities. Because of its narrow therapeutic index and potential for seizures, it is especially important in the clinical setting to adhere to the dosing recommended in the approved labels.

Symptomatic therapy in multiple sclerosis: a review for a multimodal approach in clinical practice

As more investigations into factors affecting the quality of life of patients with multiple sclerosis (MS) are undertaken, it is becoming increasingly apparent that certain comorbidities and associated symptoms commonly found in these patients differ in incidence, pathophysiology and other factors compared with the general population. Many of these MS-related symptoms are frequently ignored in assessments of disease status and are often not considered to be associated with the disease. Research into how such comorbidities and symptoms can be diagnosed and treated within the MS population is lacking. This information gap adds further complexity to disease management and represents an unmet need in MS, particularly as early recognition and treatment of these conditions can improve patient outcomes. In this manuscript, we sought to review the literature on the comorbidities and symptoms of MS and to summarize the evidence for treatments that have been or may be used to alleviate them.

Prevalence of epilepsy in a case series of multiple sclerosis patients

OBJECTIVE

The prevalence of epilepsy in multiple sclerosis (MS) patients has been a subject of interest for some years. The objectives of this study were to describe the clinical, radiological and electroencephalographic characteristics of epileptic seizures and to calculate the prevalence of epilepsy in a case series of MS patients.

METHOD

Medical charts of MS patients were reviewed and patients who had suffered epileptic seizures were identified.

RESULTS

Of 160 cases analyzed, 5 had suffered epileptic seizures and one had comorbid mesial hippocampal sclerosis, confirmed by magnetic resonance imaging in a patient with complex partial seizures that began fifteen years prior to her diagnosis of MS. In the other four patients, seizures occurred both during the acute phase of the disease and in the chronic phase.

CONCLUSION

The prevalence of epileptic seizures in MS patients in this study was 2.5%, similar to that found in other studies.

A quantitative analysis of suspected environmental causes of MS

BACKGROUND

Multiple sclerosis (MS) is a disease with purported environmental causes. Consistent correlations have been found in various settings for latitude, smoking exposure, sunlight, and vitamin D deficiency. We analysed the contribution of various environmental factors to the risk of developing MS from a population perspective.

METHODS

We collated global data of MS prevalence from 54 studies over the previous ten years and calculated the degree of risk contributed by latitude, longitude, ultraviolet radiation (from NASA satellite data and formulae for available sunlight hours), population smoking rates (from WHO data), gender, study date, study demographics, and several socioeconomic factors. We report a very significant negative correlation between MS prevalence and available ultraviolet (UV) radiation.

RESULTS

The lack of available UV radiation outweighs other factors by at least 20 fold (p < 10⁻⁸) from single variate regression analysis. Multiple regression analysis revealed that latitude and longitude are also significant factors; smoking may also provide a very minimal role. The eight prevalence studies from Scandinavia produced prevalences that were lower than expected, given their global geospatial positioning.

CONCLUSIONS

The available ultraviolet radiation is a significant environmental factor, more so than all the other factors examined.

Multiple sclerosis and epileptic seizures

Background: The association between epilepsy and multiple sclerosis (MS) is not a coincidence.

Objective: Our objective was to compare MS patients with or without history of seizures.

Methods: In a population of 5041 MS patients, we identified 102 (2%) patients with epileptic seizures. In 67 patients (1.3%), epileptic seizure could not be explained by any cause other than MS.

Results: In these 67 patients, the median age at occurrence of the first epileptic seizure was 33 years. Epilepsy was the initial clinical manifestation of MS in seven patients. In total, 62 patients (92.5%) presented only one or a few seizures, and 18 patients (27%) presented at least one episode of status epilepticus, fatal in two. Compared with MS patients without epilepsy, there was no difference in gender, type of MS course and time from onset of MS to the progressive phase. Conversely, the median age at MS onset was earlier (25.0 years vs. 30, p < 0.0001) and there was a trend for a shorter time from MS onset to non-reversible disability.

Conclusions: Our study confirms an increased risk of epileptic seizures in MS patients. It underlines that seizures may be the first observable symptom in MS and the frequency and seriousness of status epilepticus.

Neurological comorbidity and epilepsy: implications for treatment

Epilepsy is a chronic condition that may be associated with several other diseases. In these cases, we should consider the following points: (1) antiepileptic drug (AED) treatment may positively or negatively affect comorbid disease, (2) drugs used for treatment of co-morbid disease may influence seizure threshold, (3) AED toxicity can be affected by a comorbid condition and (4) co-administration of AEDs with drugs used for treatment of comorbid conditions can be associated with clinically relevant drug-drug interactions. In this article, we discuss problems that are usually encountered when an appropriate AED treatment has to be selected in newly diagnosed epileptic patients who also have (an)other neurological disease(s). Comorbidity of epilepsy with cerebrovascular diseases, dementias, mental retardation, attention deficit and hyperactivity disorder, brain tumours, infections of the CNS, migraine, sleep disturbances (obstructive sleep apnoea syndrome), substance abuse and multiple sclerosis is discussed.

Seizures in patients with multiple sclerosis: epidemiology, pathophysiology and management

Seizures have been recognized to occur in multiple sclerosis (MS) since early descriptions of the disease. Various studies have attempted to determine the incidence and prevalence of seizures in MS; although they differ in the reported prevalence, seizures do appear to be more common in MS cohorts than in the general population. The pathological underpinning of seizures in MS remains indeterminate. Cortical and subcortical demyelination and inflammation may explain the increased frequency of seizures in MS, although this hypothetical correlation remains to be proven. Management of seizures in MS is similar to the management of seizures in other patients. Consideration of the underlying neurological deficits related to MS may be necessary, and dosages of antiepileptic drugs should be adjusted if increased sensitivity to the adverse effects of these agents or interaction with other centrally acting medications is suspected. The prognosis of epilepsy in patients with MS remains uncertain, with some studies suggesting a more favourable prognosis than others.