Regional variation of multiple sclerosis prevalence in Canada

The Canadian Collaborative Project on Genetic Susceptibility to Multiple Sclerosis cohort population structure and disease etiology

Background

Previous genetic and epidemiological studies have examined subpopulations from the Canadian Collaborative Project on Genetic Susceptibility to Multiple Sclerosis (CCPGSMS) patient cohort, but an encompassing analysis of the study population has not yet been carried out.

Objective

This study examines patterns of multiple sclerosis (MS) prevalence in 13,663 cohort members, including 4,821 patients with MS or suspected MS and 8,842 family members.

Methods

We grouped participants into epidemiologic subgroups based on age of MS onset, clinical stage at diagnosis, symptom type at disease onset, sex, proband status, disability as measured by the EDSS, and ancestry based on reported ethnicity.

Results

We observed a 2.7:1 MS prevalence ratio of women to men, though disease severity was greater for male patients. Variation in the age of disease onset between patients was only slightly associated with sex and strongly associated with disease type. Specific types of clinical symptoms at disease onset were associated with the prognosis. Regional residence did not correlate with disease onset, type, or severity.

Conclusion

Population trends, as presented here, are not explained by environmental factors alone, highlighting the need for a comprehensive genetic analysis to understand disease variance across families.

Task-oriented exercise effects on walking and corticospinal excitability in multiple sclerosis: protocol for a randomized controlled trial

BACKGROUND

Multiple sclerosis (MS) is a degenerative disease of the central nervous system (CNS) that disrupts walking function and results in other debilitating symptoms. This study compares the effects of 'task-oriented exercise' against 'generalized resistance and aerobic exercise' and a 'stretching control' on walking and CNS function in people with MS (PwMS). We hypothesize that task-oriented exercise will enhance walking speed and related neural changes to a greater extent than other exercise approaches.

METHODS

This study is a single-blinded, three-arm randomized controlled trial conducted in Saskatchewan, Canada. Eligible participants are those older than 18 years of age with a diagnosis of MS and an expanded Patient-Determined Disease Steps (PDDS) score between 3 ('gait disability') and 6 ('bilateral support'). Exercise interventions are delivered for 12 weeks (3 × 60-min per week) in-person under the supervision of a qualified exercise professional. Interventions differ in exercise approach, such that task-oriented exercise involves weight-bearing, walking-specific activities, while generalized resistance and aerobic exercise uses seated machine-based resistance training of major upper and lower body muscle groups and recumbent cycling, and the stretching control exercise involves seated flexibility and relaxation activities. Participants are allocated to interventions using blocked randomization that stratifies by PDDS (mild: 3-4; moderate: 5-6). Assessments are conducted at baseline, post-intervention, and at a six-week retention time point. The primary and secondary outcome measures are the Timed 25-Foot Walk Test and corticospinal excitability for the tibialis anterior muscles determined using transcranial magnetic stimulation (TMS), respectively. Tertiary outcomes include assessments of balance, additional TMS measures, blood biomarkers of neural health and inflammation, and measures of cardiorespiratory and musculoskeletal fitness.

DISCUSSION

A paradigm shift in MS healthcare towards the use of "exercise as medicine" was recently proposed to improve outcomes and alleviate the economic burden of MS. Findings will support this shift by informing the development of specialized exercise programming that targets walking and changes in corticospinal excitability in PwMS.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT05496881, Registered August 11, 2022. https://classic.

CLINICALTRIALS

gov/ct2/show/NCT05496881 . Protocol amendment number: 01; Issue date: August 1, 2023; Primary reason for amendment: Expand eligibility to include people with all forms of MS rather than progressive forms of MS only.

FutureMS cohort profile: a Scottish multicentre inception cohort study of relapsing-remitting multiple sclerosis

PURPOSE

Multiple sclerosis (MS) is an immune-mediated, neuroinflammatory disease of the central nervous system and in industrialised countries is the most common cause of progressive neurological disability in working age persons. While treatable, there is substantial interindividual heterogeneity in disease activity and response to treatment. Currently, the ability to predict at diagnosis who will have a benign, intermediate or aggressive disease course is very limited. There is, therefore, a need for integrated predictive tools to inform individualised treatment decision making.

PARTICIPANTS

Established with the aim of addressing this need for individualised predictive tools, FutureMS is a nationally representative, prospective observational cohort study of 440 adults with a new diagnosis of relapsing-remitting MS living in Scotland at the time of diagnosis between May 2016 and March 2019.

FINDINGS TO DATE

The study aims to explore the pathobiology and determinants of disease heterogeneity in MS and combines detailed clinical phenotyping with imaging, genetic and biomarker metrics of disease activity and progression. Recruitment, baseline assessment and follow-up at year 1 is complete. Here, we describe the cohort design and present a profile of the participants at baseline and 1 year of follow-up.

FUTURE PLANS

A third follow-up wave for the cohort has recently begun at 5 years after first visit and a further wave of follow-up is funded for year 10. Longer-term follow-up is anticipated thereafter.

Preliminary testing of a patient decision aid for patients with relapsing-remitting multiple sclerosis

Background

Multiple first-line disease modifying therapies (DMTs) are available for relapsing-remitting multiple sclerosis (RRMS), each with different characteristics. We developed an interactive patient decision aid (PtDA) to promote informed shared decision-making (SDM).

Objective

To test the preliminary effectiveness of the PtDA in participants with RRMS.

Methods

Knowledge, and decisional conflict were measured pre- and post- implementation of the PtDA, SDM after the consultation, and 6-month treatment patterns were observed. Differences in scores were analyzed using descriptive statistics and paired t-tests. Qualitative interviews with patients and neurologists were analyzed using thematic analysis.

Results

52 participants were recruited: most were female (81%), 40 years of age or younger (62%), and had experienced MS for less than 5 years (56%). After participants used the PtDA, there was a significant improvement in decisional conflict (change = 1.00; p < 0.001) and knowledge (change = 2.15, p < 0.001). Nearly all patients wanted SDM, and 25 (56%) reported this occurred in their consult. Qualitative results suggested the PtDA supported both patients and neurologists in making decisions.

Conclusion

This pilot study suggests that PtDA use helps RRMS patients and their clinician select a DMT. Future studies will assess the feasibility of implementation and the impact of the PtDA on timely DMT initiation and longer-term adherence.

Effect of Neuromuscular Exercises on Strength, Proprioceptive Receptors, and Balance in Females with Multiple Sclerosis

Background:

Multiple sclerosis (MS) is the third most common cause of adult neurologic disabilities. The aim of this study was to determine the effect of 8 weeks of neuromuscular exercises on strength, proprioceptive receptors, and balance of women with MS.

Methods:

In this randomized controlled trial study, 20 female volunteers with relapsing-remitting MS were randomly assigned into the experimental group (n = 10) and control group (n = 10). Maximum muscular strength of knee extensor and flexor muscles, knee joint proprioceptive error (Biodex), and balance (Berg Balance Scale) was measured at baseline and after 8 weeks of neuromuscular exercise. The data were analyzed using paired t-test and independent t-test.

Results:

The results showed a significant improvement (P < 0.05) in the quadriceps strength, hamstring strength, proprioceptive receptor error, and the balance in the experimental group, but not in the control group. A significant difference was evident between the experimental and control groups in terms of strength, balance, and proprioceptive receptor error (P < 0.05).

Conclusions:

Neuromuscular exercise training is effective in improving balance, strength, and reducing the proprioceptive error in people with MS, and it could be recommended as modalities for these patients.

Multiple Sclerosis Clinic Utilization is Associated with Fewer Emergency Department Visits

OBJECTIVE

Alberta is a Canadian province with a high prevalence of multiple sclerosis (MS). In this ecological study, we examined group differences in health care utilization among persons with MS (pwMS) living within different regions of the province.

METHODS

pwMS were identified from provincial administrative databases spanning 2002-2011. Utilization of health care services was determined for a 2-year period (April 2010-March 2012). Residential postal codes placed patients into their provincial health care zones. As data were provided to the investigators in an aggregated form, tests of statistical significance and confounding were not performed.

RESULTS

In total, 11,721 pwMS were identified. During the 2-year observation period, 96.2% of pwMS accessed a family physician and 57.1% accessed a neurologist. Nearly all (99.0%) pwMS who received neurologist care in Calgary visited an MS clinic, in contrast to Edmonton where a larger proportion (34.8%) received solely community neurologist care. More pwMS living in Edmonton accessed the ED (41.1%) compared to Calgary (35.7%), and the rate of visits per pwMS was higher in Edmonton (1.07/pwMS) than in Calgary (0.81/pwMS). The frequency of inpatient admissions was similar.

CONCLUSIONS

Over 2 years, most pwMS accessed primary care and over half saw a neurologist. Despite a similar frequency of inpatient admissions, the frequency of ED visits by pwMS was higher in Edmonton compared to Calgary, where more patients received MS clinic care. Although this exploratory study is subject to several limitations, our findings suggest that specialized MS clinics may reduce costly ED visits.

Dysregulation of metabolic pathways by carnitine palmitoyl-transferase 1 plays a key role in central nervous system disorders: experimental evidence based on animal models

The etiology of CNS diseases including multiple sclerosis, Parkinson’s disease and amyotrophic lateral sclerosis remains elusive despite decades of research resulting in treatments with only symptomatic effects. In this study, we provide evidence that a metabolic shift from glucose to lipid is a key mechanism in neurodegeneration. We show that, by downregulating the metabolism of lipids through the key molecule carnitine palmitoyl transferase 1 (CPT1), it is possible to reverse or slowdown disease progression in experimental models of autoimmune encephalomyelitis-, SOD1^G93A and rotenone models, mimicking these CNS diseases in humans. The effect was seen both when applying a CPT1 blocker or by using a Cpt1a P479L mutant mouse strain. Furthermore, we show that diet, epigenetics, and microbiota are key elements in this metabolic shift. Finally, we present a systemic model for understanding the complex etiology of neurodegeneration and how different regulatory systems are interconnected through a central metabolic pathway that becomes deregulated under specific conditions.

Multiple sclerosis and related challenges to young women's health: Canadian expert review

Multiple sclerosis (MS) is among the most common chronic neurological diseases, with a highly variable degree of disability during its long-term course. The majority of patients develop significant permanent disability later in life. MS is often diagnosed in women of childbearing age, with a 3:1 ratio of young women to young men with MS. Comorbidities such as depression, anxiety, migraines and reproductive, urological and bowel issues are common and negatively impact patients' quality of life. The objective of this supplement is to review the most common comorbidities occurring in young women with MS, and to propose a multidisciplinary, holistic approach to management.

Neighbourhood environments and the risk of hospital admission for cardiometabolic and mental health comorbidities in multiple sclerosis: A population cohort analysis using linked administrative data

This study exploits administrative data for neuroepidemiological research and examines associations between neighbourhood environments and risk of hospitalization among multiple sclerosis (MS) patients in New Brunswick, Canada. We created a provincial database of MS patients by linking administrative health records with geographic-based characteristics of local communities. Using Cox models, we found the risk of admission for cardiometabolic complications was lower among residents of ethnically homogeneous neighbourhoods (hazards ratio [HR]: 0.75 [95% confidence interval (CI): 0.60-0.95]); that for mental health disorders was higher in socioeconomically deprived (HR: 1.80 [95% CI: 1.06-3.05]) and residentially unstable (HR: 1.61 [95% CI: 1.05-2.46]) neighbourhoods. Results suggest that selected neighbourhood environments may be associated with differential hospital burden among MS patients.

CPT1A plays a key role in the development and treatment of multiple sclerosis and experimental autoimmune encephalomyelitis

Human mutations in carnitine palmitoyl transferase 1A (CPT1A) are correlated with a remarkably low prevalence of multiple sclerosis (MS) in Inuits (P479L) and Hutterites (G710E). To elucidate the role of CPT1A, we established a Cpt1a P479L mouse strain and evaluated its sensitivity to experimental autoimmune encephalomyelitis (EAE) induction. Since CPT1a is a key molecule in lipid metabolism, we compared the effects of a high-fat diet (HFD) and normal diet (ND) on disease progression. The disease severity increased significantly in WT mice compared to that in Cpt1 P479L mice. In addition, WT mice receiving HFD showed markedly exacerbated disease course when compared either with Cpt1a P479L mice receiving HFD or WT control group receiving ND. Induction of EAE caused a significant decrease of myelin basic protein expression in the hindbrain of disease affected WT mice in comparison to Cpt1a P479L mice. Further, WT mice showed increased expression of oxidative stress markers like Nox2 and Ho-1, whereas expression of mitochondrial antioxidants regulator Pgc1α was increased in Cpt1a P479L mice. Our results suggest that, lipids metabolism play an important role in EAE, as shown by the higher severity of disease progression in both WT EAE and WT EAF HFD-fed mice in contrast to their counterpart Cpt1a P479L mutant mice. Interestingly, mice with downregulated lipid metabolism due to the Cpt1a P479L mutation showed resistance to EAE induction. These findings support a key role for CPT1A in the development of EAE and could be a promising target in MS treatment.

Development and usability testing of a patient decision aid for newly diagnosed relapsing multiple sclerosis patients

BACKGROUND

Multiple sclerosis (MS) patients often struggle with treatment decisions, in part due to the increasing number of approved disease modifying therapies, each with different characteristics, and also since physicians can struggle to identify which of these characteristics matter most to each individual patient. Decision uncertainty can contribute to late treatment initiation and treatment non-adherence-causes of 'undertreatment' in MS. An interactive online patient decision aid that informs patients of their options, considers their individual preferences and goals, and facilitates conversations with their physicians, could improve how patients with relapsing forms of MS make evidence-based treatment decisions.

OBJECTIVE

To develop and evaluate a prototype patient decision aid (PtDA) for first-line disease modifying therapies for relapsing-remitting multiple sclerosis.

METHODS

Informed by previous studies and International Patient Decision Aid Standards guidelines, a prototype PtDA was developed for patients with relapsing multiple sclerosis considering first line treatment. Patients with relapsing multiple sclerosis were recruited from the University of British Columbia's Multiple Sclerosis Clinic to participate in either an online survey or a focus group. Online survey participants completed the PtDA, followed by measures of acceptability, usability, and preparedness for decision-making, and provided general feedback. Focus group participants assessed usability of the revised PtDA. The analysis of qualitative and quantitative data led to improvements of the PtDA prototype.

RESULTS

The prototype PtDA received high ratings for acceptability and usability, and after its use, participants reported high-levels of preparedness for decision-making. Analysis of all qualitative data identified three key themes: the need for credible information; the usefulness of the PtDA; and the importance of normalizing and sharing experiences. Nine content areas were identified for revision. Overall, participants found the PtDA to be a valuable tool for facilitating treatment decisions.

CONCLUSIONS

This mixed methods study has led to the development of a PtDA that can support patients with RRMS as they make treatment decisions. Future studies will assess the feasibility of implementation and the impact of the PtDA on both the timely treatment initiation and longer-term adherence.

Cell death and mitochondrial dysfunction induced by the dietary non-proteinogenic amino acid L-azetidine-2-carboxylic acid (Aze)

In addition to the 20 protein amino acids that are vital to human health, hundreds of naturally occurring amino acids, known as non-proteinogenic amino acids (NPAAs), exist and can enter the human food chain. Some NPAAs are toxic through their ability to mimic protein amino acids and this property is utilised by NPAA-containing plants to inhibit the growth of other plants or kill herbivores. The NPAA L-azetidine-2-carboxylic acid (Aze) enters the food chain through the use of sugar beet (Beta vulgaris) by-products as feed in the livestock industry and may also be found in sugar beet by-product fibre supplements. Aze mimics the protein amino acid L-proline and readily misincorporates into proteins. In light of this, we examined the toxicity of Aze to mammalian cells in vitro. We showed decreased viability in Aze-exposed cells with both apoptotic and necrotic cell death. This was accompanied by alterations in endosomal-lysosomal activity, changes to mitochondrial morphology and a significant decline in mitochondrial function. In summary, the results show that Aze exposure can lead to deleterious effects on human neuron-like cells and highlight the importance of monitoring human Aze consumption via the food chain.

The Beneficial and Debilitating Effects of Environmental and Microbial Toxins, Drugs, Organic Solvents and Heavy Metals on the Onset and Progression of Multiple Sclerosis

Multiple sclerosis (MS), a chronic inflammatory disease of the central nervous system is common amongst young adults, leading to major personal and socioeconomic burdens. However, it is still considered complex and challenging to understand and treat, in spite of the efforts made to explain its etiopathology. Despite the discovery of many genetic and environmental factors that might be related to its etiology, no clear answer was found about the causes of the illness and neither about the detailed mechanism of these environmental triggers that make individuals susceptible to MS. In this review, we will attempt to explore the major contributors to MS autoimmunity including genetic, epigenetic and ecological factors with a particular focus on toxins, chemicals or drugs that may trigger, modify or prevent MS disease.

Comparison Between Common Performance-Based Tests and Self-Reports of Physical Function in People With Multiple Sclerosis: Does Sex or Gender Matter?

OBJECTIVE

To estimate the extent to which sex or gender differences affect the relations between tests of physical performance and self-reports about function in everyday life activities. Ecological validity is an important psychometric property when choosing tests of physical function, because they need to relate to everyday function. In multiple sclerosis (MS), the EQUI scale, modified Canadian Aerobic Fitness Test, grip strength, vertical jump, push-up, partial curl-up, gait speed (comfortable or fast), 6-minute walk test, and 9-hole peg test are commonly used but the extent to which they relate to everyday function is understudied and the extent to which ecological validity of these tests differ between women and men is unknown.

DESIGN

A cross-sectional analysis was conducted on a random sample of men and women recruited for a study on the life effect of MS. Correlations between pairs of performance outcome (PerfO) and self-reported outcome (SRO) items pairs of variables with theoretical coherence were calculated and gender effects identified using linear regression.

SETTING

Participants were recruited from MS clinic at Montreal Neurological Hospital.

PARTICIPANTS

The sample (N=188) consisted of 140 women and 48 men with MS.

INTERVENTIONS

Not applicable.

RESULTS

The mean age ± SD of the participants was 43±10. Sixty PerfO and SRO items yielded 165 theoretically linked pairs separately for women and men. Of these 330 possible pairs, 77 pairs (23%) had correlations ≥0.8, showing strong support for the link between performance tests and everyday function; 203 pairs provided moderate support (r≥0.5). Thirty-one pairs had a statistically significant interaction with gender with men having higher correlations than women (n=27/31).

CONCLUSION

The results support the ecological validity for physical performance tests, particularly balance tests and particularly for men. The observation that many indicators of everyday function derived from SROs were related to physical performance supports the routine use of SROs in clinical practice to guide therapy to meet the needs of clients with MS.

A Systematic Assessment of Prevalence, Incidence and Regional Distribution of Multiple Sclerosis in Bavaria From 2006 to 2015

Introduction: Worldwide, incidence and prevalence of multiple sclerosis (MS) have increased over the last decades. We present a systematic epidemiological study with recent prevalence and incidence rates of MS in Bavaria. Methods: Incidence and prevalence of MS stratified by gender, age groups and region were analyzed by data records from 2006 to 2015 of more than 10 million people insured by the Bavarian Association of Statutory Health Insurance Physicians. Official statistics of the German Federal Ministry of Health provided the size of the general population. Future prevalence was estimated with a predictive model. Results: From 2006 to 2015 prevalence of MS in Bavaria increased from 171 per 100,000 to 277 per 100,000, while incidence rates remained relatively stable (range 16-18 per 100,000 inhabitants with a female to male ratio between 2.4:1 and 2:1). Incidence and prevalence were higher in urban than urbanized and rural areas. The prevalence is expected to increase to 374 per 100,000 in 2040 with the highest prevalence rates between 50 and 65 years. Conclusion: The prevalence of MS in Bavaria is among the highest worldwide and will further rise over the next two decades. This demonstrates a need to strengthen healthcare provision systems due to the increasing numbers of particularly older patients with MS in the future.

Establishing the Incidence and Prevalence of Multiple Sclerosis in Saskatchewan

OBJECTIVE

To validate a case definition of multiple sclerosis (MS) using health administrative data and to provide the first province-wide estimates of MS incidence and prevalence for Saskatchewan, Canada.

METHODS

We used population-based health administrative data between January 1, 1996 and December 31, 2015 to identify individuals with MS using two potential case definitions: (1) ≥3 hospital, physician, or prescription claims (Marrie definition); (2) ≥1 hospitalization or ≥5 physician claims within 2 years (Canadian Chronic Disease Surveillance System [CCDSS] definition). We validated the case definitions using diagnoses from medical records (n=400) as the gold standard.

RESULTS

The Marrie definition had a sensitivity of 99.5% (95% confidence interval [CI] 92.3-99.2), specificity of 98.5% (95% CI 97.3-100.0), positive predictive value (PPV) of 99.5% (95% CI 97.2-100.0), and negative predictive value (NPV) of 97.5% (95% CI 94.4-99.2). The CCDSS definition had a sensitivity of 91.0% (95% CI 81.2-94.6), specificity of 99.0% (95% CI 96.4-99.9), PPV of 98.9% (95% CI 96.1-99.9), and NPV of 91.7% (95% CI 87.2-95.0). Using the more sensitive Marrie definition, the average annual adjusted incidence per 100,000 between 2001 and 2013 was 16.5 (95% CI 15.8-17.2), and the age- and sex-standardized prevalence of MS in Saskatchewan in 2013 was 313.6 per 100,000 (95% CI 303.0-324.3). Over the study period, incidence remained stable while prevalence increased slightly.

CONCLUSION

We confirm Saskatchewan has one of the highest rates of MS in the world. Similar to other regions in Canada, incidence has remained stable while prevalence has gradually increased.

Lower prevalence of multiple sclerosis in First Nations Canadians

Background

We compared the incidence and prevalence of multiple sclerosis (MS) between First Nations (FN) and non-FN populations in Manitoba.

Methods

We applied previously validated algorithms to population-based administrative (health claims) data from Manitoba, Canada, to identify all persons with MS from 1984 to 2011. We identified FN individuals using the Municipality of Registration field held at Manitoba Health. We compared the incidence and prevalence of MS between the FN and non-FN populations using negative binomial models.

Results

From 1984 to 2011, 5,738 persons had MS, of whom 64 (1.1%) were of FN ethnicity. The average annual incidence rate per 100,000 population was 8.15 (95% confidence interval [CI] 5.98–11.1) in the FN population and 15.7 (95% CI 15.1–16.3) in the non-FN population (incidence rate ratio 0.52; 95% CI 0.38–0.71). In 1984, the crude prevalence of MS per 100,000 population was 35.8 (95% CI 14.9–86.1) in the FN population and 113.3 (95% CI 106.3–120.8) in the non-FN population. Between 1984 and 2011, the age-standardized prevalence of MS increased by 351% to 188.5 (95% CI 146.6–230.4) in the FN population. In contrast, the prevalence of MS per 100,000 general population increased by 225%–418.4% (95% CI 405.8–431.0).

Conclusions

The incidence and prevalence of MS are twofold lower in the FN population than the non-FN population. Nonetheless, the prevalence of MS in FN Manitobans is higher than in other indigenous populations outside Canada. Given reports of more rapid disability progression among FN Canadians with MS, and the rising prevalence of MS in this population, attention should be directed to the needs of this population.

Clinical Profile of Persons with Multiple Sclerosis Across the Continuum of Care

Background:This study is part of the Innovations in Data, Evidence and Applications for Persons with Neurological Conditions project to understand the strengths, preferences, and needs of persons with neurological conditions living in Canada.Objective:To estimate the prevalence and describe the sociodemographic and clinical characteristics of persons with multiple sclerosis in Canadian home care, nursing home, Complex Continuing Care hospitals, and inpatient mental health care settings.Methods:Cross-sectional study of adults aged 18 years and older with multiple sclerosis (MS; n=11,250) across Canada from 1996 through 2011 using interRAI Resident Assessment Instrument (RAI) comprehensive health assessments (RAI Minimum Data Set 2.0, RAI-Home Care, RAI-Mental Health). Comparisons were made to adults with Alzheimer’s disease and related dementias (n=260,910), other neurological conditions (n=163,578) and non-neurological conditions (n=571,567).Results:The prevalence of MS was highest in Complex Continuing Care hospitals (4125 cases per 100,000 patients), followed by home care (2020 cases per 100,000 patients), nursing homes (1424 cases per 100,000 patients), and mental health settings (138 cases per 100,000 patients). Persons with MS experienced greater impairment in the completion of activities of daily living, pain, pressure ulcers, swallowing difficulty, depression, and anxiety compared with peers within care settings. There were also significant differences between settings, particularly the degree of physical and cognitive impairment experienced by persons with MS.Conclusions:Except for mental health care settings, the prevalence of MS in community, institutional and hospital-based care settings exceeded that of the general population. These data describing the sociodemographic and clinical characteristics of persons with MS may be used to inform clinical practice and policy decisions for persons with MS across the continuum of care.

A Social History of Disease: Contextualizing the Rise and Fall of Social Inequalities in Cause-Specific Mortality

Fundamental cause theory posits that social inequalities in health arise because of unequal access to flexible resources, including knowledge, money, power, prestige, and beneficial social connections, which allow people to avoid risk factors and adopt protective factors relevant in a particular place. In this study, we posit that diseases should also be put into temporal context. We characterize diseases as transitioning through four stages at a given time: (1) natural mortality, characterized by no knowledge about risk factors, preventions, or treatments for a disease in a population; (2) producing inequalities, characterized by unequal diffusion of innovations; (3) reducing inequalities, characterized by increased access to health knowledge; and (4) reduced mortality/disease elimination, characterized by widely available prevention and effective treatment. For illustration, we pair an ideal-types analysis with mortality data to explore hypothesized incidence rates of diseases. Although social inequalities exist in incidence rates of many diseases, the cause, extent, and direction of inequalities change systematically in relation to human intervention. This article highlights opportunities for further development, specifically highlighting the role of stage duration in maintaining social inequalities in cause-specific mortality.

Dialectical Behavior Group Therapy is Feasible and Reduces Emotional Dysfunction in Multiple Sclerosis

We examined whether dialectical behavior therapy (DBT) was feasible and effective in multiple sclerosis (MS). A convenience sample of 20 patients with anxiety or depression symptoms received either DBT (n = 10) or standard medical care (n = 10). The DBT protocol was found to be feasible in the MS population studied (e.g., good retention and acceptability). For the DBT group, significant improvements were demonstrated in self-rated and clinician-rated depressive symptoms, clinician-rated anxiety symptoms, self-rated general psychopathology symptoms, and quality of life. In contrast, the standard medical care group retained for exploratory purposes showed no significant improvements. This pilot work provides preliminary support for the utility of DBT in MS, but further work is needed to clarify this benefit using a large, randomized controlled approach.

Multiple sclerosis in pregnancy: prevalence, sociodemographic features, and obstetrical outcomes

OBJECTIVE

We sought to describe the prevalence, sociodemographic features, and antenatal/peripartum outcomes of multiple sclerosis (MS) in pregnancy.

STUDY DESIGN

A retrospective cohort study was performed using deliveries in California from 2001 to 2009. Cases of MS as well as other morbidities were identified via ICD-9-CM code. Logistic regression was performed to adjust for potential confounders.

RESULTS

About 1185 out of 4,424,049 deliveries were complicated by MS. MS prevalence increased with maternal age, with Caucasians comprising a higher proportion of MS subjects. MS subjects were older and more likely to have private insurance. Women with MS were more likely to have preexisting medical conditions such as asthma, chronic hypertension, thyroid disease, or cardiac disease. However, no significant antepartum and peripartum morbidities were found to be increased in patients with MS. Urinary tract infection, cesarean delivery, and induction of labor were slightly increased in MS patients.

CONCLUSIONS

MS is a rare condition which is more likely to affect older Caucasian women of higher socioeconomic status and is associated with several preexisting medical conditions. MS, however, does not appear to pose significant increases in adverse pregnancy outcome. This suggests that pregnant patients with MS may likely experience an uneventful pregnancy.

Adherence to disease-modifying therapies for multiple sclerosis and subsequent hospitalizations

PURPOSE

The aim of this study was to examine the association between optimal adherence to first-line disease-modifying therapies (DMT) for multiple sclerosis (MS) and hospitalizations.

METHODS

We used population-based administrative data from three Canadian provinces. All individuals receiving DMT (interferon-B-1b, interferon-B-1a, or glatiramer acetate) between January 1, 1996, and December 31, 2011 (British Columbia); March 31, 2012 (Manitoba); or March 31, 2014, (Saskatchewan) were included. Adherence was estimated for the first year of DMT (year 0), using the medication possession ratio (MPR). The association between optimal adherence (MPR ≥ 80%) and all-cause and MS-specific hospitalizations in the subsequent 1, 2, and 5 years was assessed using Hurdle Poisson and logistic regression. Rate and odds ratios were adjusted (aRR and aOR) for sociodemographic factors and prior health-care utilization.

RESULTS

Overall, 4746 subjects were followed for a mean 7.8 (SD 4.0) years; 3598 (76%) were women. Optimal DMT adherence was achieved in 3564/4746 (75.1%) subjects. Subsequent all-cause and MS-specific hospitalizations were lower for subjects with optimal versus suboptimal adherence, but none reached statistical significance (1-year period, aRR = 0.77, 95%CI: 0.47-1.26; aOR = 0.80, 95%CI: 0.52-1.25). Similar findings were observed in the 2-year and 5-year periods. Prior health-care utilization (hospitalizations and medications) was associated with future hospitalizations; for every additional medication class, the 5-year all-cause hospitalization rate and likelihood of an MS-specific hospitalization increased by 5% and 11%, respectively (aRR = 1.05, 95%CI: 1.02-1.07; and aOR = 1.11, 95%CI: 1.07-1.14).

CONCLUSIONS

Hospitalization rates were lower in subjects with optimal DMT adherence, but findings were not statistically significant. Prior hospitalization and polypharmacy were associated with increased risk for future hospitalizations in MS. Copyright © 2017 John Wiley & Sons, Ltd.

High prevalence and increasing incidence of multiple sclerosis in the Norwegian county of Buskerud

OBJECTIVES

The objective was to investigate the incidence of multiple sclerosis (MS) as well as estimate the prevalence as of 1 January 2014 in the southeastern Norwegian county of Buskerud.

MATERIALS AND METHODS

All patients with MS living in Buskerud county in Norway between 01 January 2003 and 01 January 2014 were identified. Point prevalence of MS was identified on 01 January 2014.

RESULTS

We found a prevalence of 213.8 (95% CI 196.4-231.1) per 100 000. The sex ratio was 2.2:1 with a female prevalence of 293.4 (95% CI 264.7-322.2) per 100 000 and a male prevalence of 134.7 (95% CI 115.3-154.2) per 100 000. About 82% of our MS population had a confirmed relapsing-remitting MS at disease onset, while 16.8% had primary progressive MS. The mean annual incidence between 2003 and 2013 was 11.8 (95% CI 10.6-13.1) per 100 000.

CONCLUSION

This study shows a high incidence of MS in Buskerud county in southeastern Norway, and the incidence may still be on the rise. We found a relatively high prevalence of MS in our population, although this does correspond with the recently published national data. Further studies investigating both changes in incidence and possible factors causing the increasing incidence are warranted.

Public Funding and Open Access to Research: A Review of Canadian Multiple Sclerosis Research

Background

Multiple sclerosis (MS), a progressive demyelinating disease of the brain and spinal cord, is the leading cause of nontraumatic neurological damage in young adults. Canada has one of the highest reported incidents of MS, with estimates between 55 and 240 per 100,000 individuals. Between 2009 and 2014, the MS Society of Canada provided over Can $90 million to researchers and, since 2013, has encouraged researchers to make both current and previous research products openly available.

Objective

The goal of the study was to determine the open access (OA) cost implications and repository policies of journals frequently used by a sample of MS researchers. This study benchmarked current publishing preferences by MS Society of Canada researchers by examining the OA full-text availability of journal articles written by researchers funded between 2009 and 2014.

Methods

Researchers were identified from the 2009 to 2014 annual MS Society of Canada Research Summaries. Articles were identified through searches in Web of Science, Scopus, Medline and Embase (both via OVID). Journal level analysis included comparison of OA policies, including article processing charges (APCs) and repository policies. Data were analyzed using descriptive statistics.

Results

There were 758 articles analyzed in this study, of which 288 (38.0%) were OA articles. The majority of authors were still relying on journal policies for deposit in PubMed Central or availability on publisher websites for OA. Gold OA journals accounted for 10.2% of the journals in this study and were associated with significantly lower APCs (US $1900) than in hybrid journals (US $3000). Review of the journal self-archiving options highlighted the complexity of stipulations that authors would have to navigate to legally deposit a version of their article.

Conclusions

This study found that there are currently researcher- and publisher-imposed barriers to both the gold and green roads to OA. These results provide a current benchmark against which efforts to enhance openness can be measured and can serve as a reference point in future assessments of the impact of OA policies within this field. With funding agencies worldwide releasing OA mandates, future success in compliance will require changes to how researchers and publishers approach production and dissemination of research.

Correlation of geographic distributions of haptoglobin alleles with prevalence of multiple sclerosis (MS) - a narrative literature review

We have proposed that the myelin damage observed in multiple sclerosis (MS) may be partly mediated through the long-term release and degradation of extracellular hemoglobin (Hb) and the products of its oxidative degradation [Cellular and Molecular Life Sciences, 71, 1789-1798, 2014]. The protein haptoglobin (Hpt) binds extracellular Hb as a first line of defense, and can serve as a vascular antioxidant. Humans have two different Hpt alleles: Hpt1 and Hpt2, giving either homozygous Hpt1-1 or Hpt2-2 phenotypes, or a heterozygous Hpt1-2 phenotype. We questioned whether those geographic regions with higher frequency of the Hpt2 allele (conversely, lower frequency of Hpt1 allele) would correlate with an increased incidence of MS, because different Hpt phenotypes will have variable anti-oxidative potentials in protecting myelin from damage inflicted by extracellular Hb and its degradation products. To test this hypothesis, we undertook a systematic analysis of the literature on reported geographic distributions of Hpt alleles to compare them with data reported in the World Health Organization Atlas of worldwide MS prevalence. We found the frequency of the Hpt1 allele to be low in European and North American countries with a high prevalence of MS, consistent with our hypothesis. However, this correlation was not observed in China and India, countries with the lowest Hpt1 frequencies, yet low reported prevalence of MS. Nevertheless, this work shows the need for continued refinement of geographic patterns of MS prevalence, including data on ethnic or racial origin, and for new clinical studies to probe the observed correlation and evaluate Hpt phenotype as a predictor of disease variability and progression, severity, and/or comorbidity with cardiovascular disorders.

Epidemiology of Multiple Sclerosis

The epidemiology of multiple sclerosis (MS) includes a consideration of genetic and environmental factors. Comparative studies of different populations have revealed prevalence and incidence rates that vary with geography and ethnicity. With a prevalence ranging from 2 per 100,000 in Japan to greater than 100 per 100,000 in Northern Europe and North America, the burden of MS is similarly unevenly influenced by longevity and comorbid disorders. Well-powered genome-wide association studies have investigated the genetic substrate of MS, providing insight into autoimmune mechanisms involved in the etiopathogenesis of MS and elucidating possible avenues of biological treatment.

The Standards of Reporting of Neurological Disorders (STROND) checklist: Application to multiple sclerosis

Background:

Descriptive epidemiological studies documenting the incidence and prevalence of multiple sclerosis (MS) and studies that report morbidity, mortality, and economic burden provide essential information for patients, healthcare providers, and policymakers. However, the quality of reporting of observational studies is often poor, limiting the ability to evaluate the validity of the findings. The Standards of Reporting of Neurological Disorders (STROND) reporting guideline comprises recommendations and a 15-item checklist of reporting items to aid high-quality reporting of incidence and prevalence studies of neurological disorders.

Methods:

We explain the basic reporting items of the STROND checklist for the methods, results, and discussion sections in the context of the MS literature and searched for examples of good reporting of those items.

Results:

We identified examples of good reporting of the basic reporting items from previous systematic reviews of the descriptive epidemiologic literature in MS.

Conclusion:

The adoption of the STROND reporting guidelines should improve the quality of reporting of descriptive epidemiological studies in MS. Along with efforts to improve methodological aspects of epidemiological studies and harmonization of data collection efforts, improved reporting could contribute to furthering our understanding of the epidemiology of MS.

Adherence to interferon β-1a therapy using an electronic self-injector in multiple sclerosis: a multicentre, single-arm, observational, phase IV study

BACKGROUND

In a multicentre, single-arm, observational, phase IV study, we evaluated 24-week treatment adherence of relapsing multiple sclerosis (RMS) patients using an electronic auto-injection device (RebiSmart(®)) for subcutaneous injection of interferon (IFN) β-1a.

METHODS

A total of 162 adult participants with RMS were enrolled into the study to use RebiSmart(®) to self-administer IFN β-1a 44 μg three times weekly for a maximum of 96 weeks. The number of administered injections was recorded in the electronic device log. Adherence to treatment was defined as the administration of ≥80% of expected injections. Cognitive impairment and injection anxiety were assessed via questionnaires.

RESULTS

Overall, 91.8 and 82.9% of participants were adherent to treatment at weeks 12 and 24, respectively. By weeks 12 and 24, 8.2 and 13.9% of participants had discontinued treatment. There were no statistically significant differences in adherence rates at weeks 12 and 24 according to cognitive impairment status or injection anxiety. By week 24, 69.9% of participants were less fearful of injection than when they started the study. According to participant evaluations, the absence of a visible needle, comfort settings, and the calendar for tracking the injection schedule were all important features of the RebiSmart(®) injection system. At week 24, 99.3% of participants reported that they would like to continue using RebiSmart(®) as their injector.

CONCLUSIONS

RebiSmart(®) use is associated with high treatment adherence, as objectively assessed using electronic injection logs. Future research should examine if RebiSmart(®) use improves long-term treatment outcomes in RMS. This study was registered with ClinicalTrials.gov as NCT01128075, on May 20, 2010.

Fatigue in Multiple Sclerosis: Assessing Pontine Involvement Using Proton MR Spectroscopic Imaging

Background/Objective

The underlying mechanism of fatigue in multiple sclerosis (MS) remains poorly understood. Our study investigates the involvement of the ascending reticular activating system (ARAS), originating in the pontine brainstem, in MS patients with symptoms of fatigue.

Methods

Female relapsing-remitting MS patients (n = 17) and controls (n = 15) underwent a magnetic resonance spectroscopic imaging protocol at 1.5T. Fatigue was assessed in every subject using the Fatigue Severity Scale (FSS). Using an FSS cut-off of 36, patients were categorized into a low (n = 9, 22 ± 10) or high (n = 10, 52 ± 6) fatigue group. The brain metabolites N-acetylaspartate (NAA) and total creatine (tCr) were measured from sixteen 5x5x10 mm³ spectroscopic imaging voxels in the rostral pons.

Results

MS patients with high fatigue had lower NAA/tCr concentration in the tegmental pons compared to control subjects. By using NAA and Cr values in the cerebellum for comparison, these NAA/tCr changes in the pons were driven by higher tCr concentration, and that these changes were focused in the WM regions.

Discussion/Conclusion

Since there were no changes in NAA concentration, the increase in tCr may be suggestive of gliosis, or an imbalanced equilibrium of the creatine and phosphocreatine ratio in the pons of relapsing-remitting MS patients with fatigue.

Depression and hypomania symptoms are associated with high dose corticosteroids treatment for MS relapses

BACKGROUND

Psychiatric side effects are known to occur with low dose corticosteroids. Standard of care for Multiple Sclerosis (MS) relapses is high dose corticosteroids (HDC), at least 1g/day for 3-5 days, and yet the relationship between this treatment and mood is not known. We sought to determine the frequency and potential predictors of (hypo)manic and depressive symptoms with HDC treatment for MS relapses.

METHODS

Consecutive MS subjects requiring HDC treatment were identified. The Mood Disorders Questionnaire (MDQ) and the Beck Depression Inventory-Fast Screen (BDIFS) were administered for (hypo)manic and depressive symptoms, respectively, prior to HDC, 3 days and one month post-HDC.

RESULTS

Eighty eight subjects completed the study. At relapse diagnosis, the mean BDIFS score was 4.2 (SD 3.1); the mean number of (hypo)manic symptoms endorsed on the MDQ was 4.3 (SD 3.5). Three days after completing HDC, 22.5% had an increase on the BDIFS and 38.2% endorsed more symptoms on the MDQ. A history of depression (p=0.006) and low reported quality of life (p=0.029) predicted an increase on the MDQ; the odds of an increase in (hypo)manic symptoms was 5.6 times higher with a history of any psychiatric disease/substance abuse (p=0.005). No predictors for worsening on the BDIFS were found.

LIMITATIONS

Self-reported measures were used, anxiety was not evaluated and 17 subjects were lost to follow up.

CONCLUSION

Depressive and hypo(manic) symptoms are commonly associated with HDC for MS relapses. It is important for clinicians and MS patients to be aware of this risk.

Rehabilitation of multiple sclerosis patients in India

Multiple sclerosis (MS) is a chronic progressive disease which is one of the leading causes of handicap in young subjects. The large range of symptoms associated with MS lead to continuing decline in neurologic status and quality of life. The coexistence of physical and cognitive impairments, together with the imprevisible evolution of the disease makes MS rehabilitation very challenging. The main objective of rehabilitation is, therefore, to ease the burden of symptoms by improving self-performance and independence. Inpatient, outpatient and Home rehabilitation with multidisciplinary team has been shown to be beneficial in improving disability. Individualized programs elaborated by a multidisciplinary team of experts are the key to success of rehabilitation. Family plays a big role and Family Based Rehabilitation will be important in long term rehab program in MS.

High incidence and increasing prevalence of multiple sclerosis in British Columbia, Canada: findings from over two decades (1991-2010)

Province-wide population-based administrative health data from British Columbia (BC), Canada (population: approximately 4.5 million) were used to estimate the incidence and prevalence of multiple sclerosis (MS) and examine potential trends over time. All BC residents meeting validated health administrative case definitions for MS were identified using hospital, physician, death, and health registration files. Estimates of annual prevalence (1991–2008), and incidence (1996–2008; allowing a 5-year disease-free run-in period) were age and sex standardized to the 2001 Canadian population. Changes over time in incidence, prevalence and sex ratios were examined using Poisson and log-binomial regression. The incidence rate was stable [average: 7.8/100,000 (95 % CI 7.6, 8.1)], while the female: male ratio decreased (p = 0.045) but remained at or above 2 for all years (average 2.8:1). From 1991–2008, MS prevalence increased by 4.7 % on average per year (p < 0.001) from 78.8/100,000 (95 % CI 75.7, 82.0) to 179.9/100,000 (95 % CI 176.0, 183.8), the sex prevalence ratio increased from 2.27 to 2.78 (p < 0.001) and the peak prevalence age range increased from 45–49 to 55–59 years. MS incidence and prevalence in BC are among the highest in the world. Neither the incidence nor the incidence sex ratio increased over time. However, the prevalence and prevalence sex ratio increased significantly during the 18-year period, which may be explained by the increased peak prevalence age of MS, longer survival with MS and the greater life expectancy of women compared to men.

Effect of comorbidity on mortality in multiple sclerosis

Objective:

We aimed to compare survival in the multiple sclerosis (MS) population with a matched cohort from the general population, and to evaluate the association of comorbidity with survival in both populations.

Methods:

Using population-based administrative data, we identified 5,797 persons with MS and 28,807 controls matched on sex, year of birth, and region. We estimated annual mortality rates. Using Cox proportional hazards regression, we evaluated the association between comorbidity status and mortality, stratifying by birth cohort, and adjusting for sex, socioeconomic status, and region. We compared causes of death between populations.

Results:

Median survival from birth in the MS population was 75.9 years vs 83.4 years in the matched population. MS was associated with a 2-fold increased risk of death (adjusted hazard ratio 2.40; 95% confidence interval: 2.24–2.58). Several comorbidities were associated with increased hazard of death in both populations, including diabetes, ischemic heart disease, depression, anxiety, and chronic lung disease. The magnitude of the associations of mortality with chronic lung disease, diabetes, hypertension, and ischemic heart disease was lower in the MS population than the matched population. The most common causes of death in the MS population were diseases of the nervous system and diseases of the circulatory system. Mortality rates due to infectious diseases and diseases of the respiratory system were higher in the MS population.

Conclusion:

In the MS population, survival remained shorter than expected. Within the MS population, comorbidity was associated with increased mortality risk. However, comorbidity did not preferentially increase mortality risk in the MS population as compared with controls.

Interferon-β suppresses murine Th1 cell function in the absence of antigen-presenting cells

Interferon (IFN)-β is a front-line therapy for the treatment of the relapsing-remitting form of multiple sclerosis. However, its immunosuppressive mechanism of function remains incompletely understood. While it has been proposed that IFN-β suppresses the function of inflammatory myelin antigen-reactive T cells by promoting the release of immunomodulatory cytokines such as IL-27 from antigen-presenting cells (APCs), its direct effects on inflammatory CD4⁺ Th1 cells are less clear. Here, we establish that IFN-β inhibits mouse IFN-γ⁺ Th1 cell function in the absence of APCs. CD4⁺ T cells express the type I interferon receptor, and IFN-β can suppress Th1 cell proliferation under APC-free stimulation conditions. IFN-β-treated myelin antigen-specific Th1 cells are impaired in their ability to induce severe experimental autoimmune encephalomyelitis (EAE) upon transfer to lymphocyte-deficient Rag1^-/- mice. Polarized Th1 cells downregulate IFN-γ and IL-2, and upregulate the negative regulatory receptor Tim-3, when treated with IFN-β in the absence of APCs. Further, IFN-β treatment of Th1 cells upregulates phosphorylation of Stat1, and downregulates phosphorylation of Stat4. Our data indicate that IFN-γ-producing Th1 cells are directly responsive to IFN-β and point to a novel mechanism of IFN-β-mediated T cell suppression that is independent of APC-derived signals.

The budget impact of introducing delayed-release dimethyl fumarate for treatment of relapse-remitting multiple sclerosis in Canada

OBJECTIVE

Multiple sclerosis (MS) causes significant disability globally and is especially prevalent in Canada. Delayed-release dimethyl fumarate (DMF; also known as gastro-resistant DMF) is an orally administered disease-modifying treatment (DMT) for patients with relapsing-remitting MS (RRMS) that is currently on the market in the US, Australia, Canada, and Europe. A budget impact model (BIM) was developed to assess the financial consequences of introducing DMF for treatment of RRMS in Canada.

METHODS

A BIM calculated the financial consequences of introducing DMF in Canada over 3 years based on RRMS prevalence, treatment market share, and clinical effects. RRMS prevalence in Canada was derived from published literature and natural relapse rates, and disease state distribution from clinical trial data. It was conservatively assumed that 100% of RRMS patients were treated with a DMT. DMF was assumed to absorb market share proportionally from the following current treatments: interferon beta-1a-IM, interferon beta-1a-SC, interferon beta-1b, and glatiramer acetate. Treatment efficacy, in terms of relapse rate reductions and treatment discontinuation rates, was determined from mixed treatment comparison. Treatment costs (including costs of acquisition, monitoring, and administration) and cost of relapse were considered. Deterministic one-way sensitivity analyses were conducted to assess the most sensitive input parameters.

RESULTS

Over 3 years, the introduction of DMF resulted in an average annual increase of CAD417 per treated patient per year, with reductions in costs associated with relapses (CAD192/patient/year) partially offsetting increased drug acquisition costs (CAD602/patient/year). On a population level, the average annual cost increase was CAD24,654,237, a CAD 0.68 increase per population covered by the Canadian healthcare system. The main drivers of budget impact were drop-out rates, proportion of RRMS patients treated, and market share assumptions.

CONCLUSIONS

The acquisition costs of DMF for treatment of RRMS are predicted to be partially offset by reduced costs of relapses in the Canadian healthcare system.

Assessment of Outcome Predictors after First Attack of Optic Neuritis

Background:

Optic Neuritis (ON) is one of the most common clinically isolated syndromes which develops into clinically diagnosed Multiple Sclerosis (CDMS) over time.

Objective:

To assess the conversion rate of Iranian patients presenting with idiopathic ON to CDMS as well as monitoring potential demographic and clinical risk factors.

Methods:

Atotal of 219 patients' medical records of idiopathic ON from March 2001 to May 2009 were reviewed. Demographic findings, ophthalmologic characteristics on admission and discharge, diagnostic approaches, type and dosage of therapy were retrospectively reviewed. A structured telephone interview was then conducted to identify patients who had subsequently been diagnosed with MS. Survival analysis was used to evaluate the cumulative probability of MS conversion and contributory risk factors.

Results:

From the 219 ON patients, 109 [age 11-51, female: 81%] were followed up. Among the male gender the mean age of patients developing MS was significantly lower (P=0.01). In cox regression model, female sex (p=0.07), bilateral ON (p=0.003), MRI abnormalities (p <0.001) and high dose (5g) corticosteroid therapy (p<0.001) were identified as risk factors for the development of MS. The two and five year cumulative probability of developing MS were 27% and 45%, respectively.

Conclusions:

Idiopathic ON in Iranian patients carries higher risk of progression to MS compared to other Asian countries. MRI lesions are the strongest independent risk factor of developing CDMS. Bilateral ON, female gender and high dose corticosteroid therapy are also important factors in predicting CDMS development.

Prevalence of Multiple Sclerosis in Canada: A Systematic Review

Background:

Studies of the prevalence of multiple sclerosis (MS) in Canada have generally been isolated to specific regions. Given the importance of multiple sclerosis as a cause of disability in adults, a comprehensive review of Canadian MS prevalence examining current data, interregional variation, deficiencies in knowledge and frontiers for research is timely.

Methods:

A systematic review of all studies addressing the prevalence of MS in Canada or regions within Canada, published in English or French since 1985, was conducted. Studies were identified using MEDLINE, EMBASE and bibliographic review. Ten studies were evaluated for methodological rigour and a test of heterogeneity across studies was performed and a measure of consistency (I2) estimated.

Results:

Studies were generally of high quality. Nine were restricted to regions within Canada and one provided an estimated national prevalence based on self-reported cases. All reported a high prevalence (>50 per 100 000). Latitude and longitude gradients were not striking while assessment of heterogeneity confirmed that regional differences were unlikely to be the result of sampling variability.

Conclusions:

This review confirms Canada as a country of very high MS prevalence and it is the first study to demonstrate that variation in regional estimates represents true differences in prevalence within Canada. Avenues for future MS prevalence research, including adoption of a national MS registry, are proposed.

Parkinson's Disease, Multiple Sclerosis and Changes of Residence in Alberta

Background:

Our objective is to examine how persons diagnosed with Multiple Sclerosis (MS) and Parkinson's disease (PD) change residence following disease onset. We hypothesize that persons choose to change residence (locally or regionally) in different ways depending on whether or not they have been diagnosed with MS/PD. We also estimate the effects of residence change on measures of disease prevalence made at several different levels of geography.

Methods:

Using fee-for service and hospitalization data, we identify cases of MS and PD between 1994 and 2004. Both of these case groups are matched to controls based on age, sex, socioeconomic status and municipality of residence. We tabulate and compare the changes of residence among persons in the case and control groups. We also use these data to estimate the effects that changes in residence have on disease prevalence at three different levels of geography.

Results:

Both MS and PD patients were more likely to change residence following disease onset compared to groups of matched controls (p<=0.001). Most changes of residence occur within the same municipality. The total magnitude of these changes is small, however, and is unlikely to affect estimates of disease prevalence; over our study period, the largest change in geographical prevalence estimates due to individual changes in residence was about 1%.

Conclusions:

Persons diagnosed with MS and PD both have mobility characteristics that differ from those of their respective control groups, and in general, are more likely to move to or between Edmonton and Calgary, and less likely to move out of province. However, the balance of mobility characteristics of persons with PD and MS appear unlikely to greatly affect the patterns observed on maps of disease prevalence.

Increasing Use of Disease Modifying Drugs for MS in Canada

Background/Objectives:

The course of multiple sclerosis may be slowed by use of the disease modifying drugs (DMDs): subcutaneous or intramuscular interferon beta-1a, interferon beta-1b, glatiramer acetate, and natalizumab. We set out to compare utilization of these drugs in the Canadian provinces from 2002-2007.

Methods:

Using a retrospective cohort analysis, we reviewed population data from International Medical Statistics (IMS) Health between November 2001 and October 2007.

Results:

The total annual number of DMD prescriptions increased from 3.9, in 2002, to 5.1, in 2007, per 1,000 Canadians. The total annual cost of prescriptions rose from $187 million to $287 million. Of the four provinces responsible for the majority of prescriptions - Alberta, BC, Ontario, and Quebec - Quebec had the highest average annual prescription rate (7 per 1,000 population) and BC had the lowest rate (3.3 per 1,000 population). Subcutaneous interferon beta-1a was the most commonly used drug whereas glatiramer acetate showed the greatest growth in use from 2002 to 2007.

Conclusions:

Disease modifying drugs prescription rates and costs increased by more than 30% between 2002 and 2007. There was wide variation in DMD prescription rates and relative drug preferences across the provinces.

Development and validation of an administrative data algorithm to estimate the disease burden and epidemiology of multiple sclerosis in Ontario, Canada

Background:

Few studies have assessed the accuracy of administrative data for identifying multiple sclerosis (MS) patients.

Objectives:

To validate administrative data algorithms for MS, and describe the burden and epidemiology over time in Ontario, Canada.

Methods:

We employed a validated search strategy to identify all MS patients within electronic medical records, to identify patients with and without MS (reference standard). We then developed and validated different combinations of administrative data for algorithms. The most accurate algorithm was used to estimate the burden and epidemiology of MS over time.

Results:

The accuracy of the algorithm of one hospitalisation or five physician billings over 2 years provided both high sensitivity (84%) and positive predictive value (86%). Application of this algorithm to provincial data demonstrated an increasing cumulative burden of MS, from 13,326 patients (0.14%) in 2000 to 24,647 patients in 2010 (0.22%). Age-and-sex standardised prevalence increased from 133.9 to 207.3 MS patients per 100,000 persons in the population, from 2000 – 2010. During this same period, age-and-sex-standardised incidence varied from 17.9 to 19.4 patients per 100,000 persons.

Conclusions:

MS patients can be accurately identified from administrative data. Our findings illustrated a rising prevalence of MS over time. MS incidence rates also appear to be rising since 2009.