Age-corrected neurofilament light chain ratio decreases but does not predict relapse in highly active multiple sclerosis patients initiating natalizumab treatment

BACKGROUND

Neurofilament light chain (NFL) is a biomarker for monitoring disease activity and treatment response in multiple sclerosis (MS). However, while most agree that NFL levels predict disease activity and worsening, the predictive value of NFL on future relapse risk remains uncertain.

OBJECTIVE

The primary aim was to evaluate the predictive value of age-corrected serum NFL (sNFL) ratio on relapse risk in highly active relapsing-remitting MS patients (RRMS) treated with natalizumab. A secondary aim was to investigate the predictive value of sNFL ratios for MRI activity.

METHODS

From January 1, 2006, to December 31, 2010, 355 patients initiated natalizumab treatment at the Danish Multiple Sclerosis Center. 305 patients were anti-natalizumab antibodies negative and had at least one blood sample available for sNFL analysis using single molecule array analysis at baseline, three, six, or 12 months. The patients were either treatment-naïve (n = 8), switching from interferon-β or glatiramer acetate (n = 253), or switching from mitoxantrone (n = 44). An age-corrected ratio was calculated for sNFL. Time to first relapse was calculated from baseline and after re-baseline at 90 days. Data were collected from baseline until the two-year follow-up or end of treatment and included disease duration, expanded disability status scale, previous treatments, relapses 12 months prior to natalizumab initiation, smoking intensity, body mass index, and body weight. In addition, the patients underwent annual MRI of the brain.

RESULTS

The sNFL ratio was increased in 173 of 287 samples (60.3 %) at baseline, in 119 of 246 samples (48.8 %) at month three, in 109 of 287 samples (38.0 %) at month six, and in 82 of 270 samples (30.4 %) at month 12. The sNFL ratio continuously declined over 12 months with significant decreases for every measuring timepoint: baseline vs. three months p = 3.0 × 10-6; three months vs. six months p = 3.2 × 10-5; six months vs. 12 months p = 0.002. Univariate Cox regression analysis showed that time to first relapse from 1) natalizumab initiation and from 2) re-baseline was associated with the number of relapses in the previous 12 months (hazard ratio 1.31 per relapse, 95 % CI = 1.2-1.5, p = 2.0 × 10-6; and 1.21 per relapse, 95 % CI = 1.1-1.4, p = 0.002, respectively). sNFL ratio at re-baseline was negatively associated with relapse risk (hazard ratio 0.82 per unit; 95 % CI = 0.7-1.0; p = 0.049). A multivariable Cox regression analysis of relapse risk from re-baseline showed that the number of relapses in the 12 months prior to natalizumab treatment (hazard ratio 1.29; 95 % CI = 1.1-1.5; p = 6.0 × 10-4) and smoking (hazard ratio 1.51 per 20 cigarettes per day; 95 % CI = 1.0-2.2; p = 0.030) were associated with increased risk of relapse; sNFL ratio was associated with a lower risk of relapse (hazard ratio = 0.736 per unit; 95 % CI = 0.6-0.9 p = 0.007). In univariate logistic regression analyses, the sNFL ratio at 12 months and values above the 75th and the 90th percentile predicted MRI activity in the following year (odds ratio [OR] = 2.0, 95 % CI = 1.2-3.6, p = 0.012; OR = 2.2, 95 % CI = 1.2-4.1, p = 0.014; and OR = 2.8, 95 % CI = 1.1-6.7, p = 0.026).

CONCLUSION

In this highly active RRMS cohort, high sNFL ratios reflected previous relapse activity and decreased after initiation of treatment but were not associated with increased relapse risk in the following two years. Pre-treatment relapses and smoking on treatment were predictors of relapse risk after re-baselining at 90 days. MRI activity in year two was predicted by sNFL ratios at month 12.

Impact of tobacco smoking on disease-specific outcomes in common neurological disorders: A scoping review

Although the association of smoking with the risk of incident neurological disorders is well established, less is known about the impact of smoking and smoking cessation on outcomes of these conditions. The objective of this scoping review was to synthesize what is known about the impact of smoking and smoking cessation on disease-specific outcomes for seven common neurological disorders. We included 67 studies on the association of smoking and smoking cessation on disease-specific outcomes. For multiple sclerosis, smoking was associated with greater clinical and radiological disease progression, relapses, risk for disease-related death, cognitive decline, and mood symptoms, in addition to reduced treatment effectiveness. For stroke and transient ischemic attack, smoking was associated with greater rates of stroke recurrence, post-stroke cardiovascular outcomes, post-stroke mortality, post-stroke cognitive impairment, and functional impairment. In patients with cognitive impairment and dementia, smoking was associated with faster cognitive decline, and smoking was also associated with greater cognitive decline in Parkinson's disease, but not motor symptom worsening. Patients with amyotrophic lateral sclerosis who smoked faced increased mortality. Last, in patients with cluster headache, smoking was associated with more frequent and longer cluster attack periods. Conversely, for multiple sclerosis and stroke, smoking cessation was associated with improved disease-specific outcomes. In summary, whereas smoking is detrimentally associated with disease-specific outcomes in common neurological conditions, there is growing evidence that smoking cessation may improve outcomes. Effective smoking cessation interventions should be leveraged in the management of common neurological disorders to improve patient outcomes.

Stroke risk in multiple sclerosis: a critical appraisal of the literature

Observational studies suggest that the occurrence of stroke on multiple sclerosis (MS) patients is higher compared to the general population. MS is a heterogeneous disease that involves an interplay of genetic, environmental and immune factors. The occurrence of stroke is subject to a wide range of both modifiable and non-modifiable, short- and long-term risk factors. Both MS and stroke share common risk factors. The immune mechanisms that underlie stroke are similar to neurodegenerative diseases and are attributed to neuroinflammation. The inflammation in autoimmune diseases may, therefore, predispose to an increased risk for stroke or potentiate the effect of conventional stroke risk factors. There are, however, additional determinants that contribute to a higher risk and incidence of stroke in MS. Due to the challenges that are associated with their differential diagnosis, the objective is to present an overview of the factors that may contribute to increased susceptibility or occurrence of stroke in MSpatients by performing a review of the available to date literature. As both MS and stroke can individually detrimentally affect the quality of life of afflicted patients, the identification of factors that contribute to an increased risk for stroke in MS is crucial for the prompt implementation of preventative therapeutic measures to limit the additive burden that stroke imposes.

Effect of smoking on disease activity in multiple sclerosis patients treated with dimethyl fumarate or fingolimod

BACKGROUND

In relapsing-remitting multiple sclerosis (RRMS), smoking is a known risk factor for disease susceptibility and disability progression. However, its impact on the efficacy of oral disease-modifying drugs (DMDs) is unclear. Therefore, we initiated a single-center, retrospective, observational study to investigate the relationship between smoking and disease activity in RRMS patients under oral DMDs.

METHODS

We retrospectively enrolled RRMS patients who initiated oral DMDs (fingolimod or dimethyl fumarate) at our hospital between January 2012 and December 2019. Clinical data and smoking status at oral DMD initiation were collected up to December 2020. We conducted survival analyses for relapse and any disease activity, defined as relapse or MRI disease activity, among patients with distinct smoking statuses.

RESULTS

We enrolled 103 RRMS patients under oral DMDs including 19 (18.4%) current smokers at baseline. Proportions of relapses and any disease activity during follow-up were higher in current smokers (relapse: p = 0.040, any disease activity: p = 0.004) and time from initiating oral DMDs to relapse was shorter in current smokers (log-rank test: p = 0.011; Cox proportional hazard analysis: hazard ratio (HR) 2.72 [95% confidence interval (CI) 1.22-6.09], p = 0.015) than in non-smokers. Time from initiating oral DMDs to any disease activity was also shorter in current smokers (log-rank test: p = 0.016; Cox proportional hazard analysis: HR 2.18 [95% CI 1.14-4.19], p = 0.019) than in non-smokers. The survival curves for relapse and any disease activity were not different between the former smoker and never-smoker groups. Multivariate survival analysis showed current smoking was an independent risk factor for relapse or any disease activity after adjusting for covariates (relapse: HR 2.54 [95% CI 1.06-6.10], p = 0.037; any disease activity: HR 3.47 [95% CI 1.27-9.50], p = 0.015).

CONCLUSION

Smoking was a risk factor for disease activity in RRMS patients under oral DMD treatment. RRMS patients should be advised to stop smoking even after the initiation of DMDs.

Paradigm shifts in multiple sclerosis management: Implications for daily clinical practice

Multiple sclerosis (MS) is the most common chronic inflammatory neurological disease. The emergence of disease-modifying therapies (DMTs) has greatly improved disease activity control and progression of disability in MS patients. DMTs differ in their mode of action, route of administration, efficacy, and safety profiles, offering multiple options for clinicians. Personalized medicine aims at tailoring the therapeutic strategy to patients' characteristics and disease activity but also patients' needs and preferences. New therapeutic options have already changed treatment paradigms for patients with active relapsing MS (RMS). The traditional approach consists in initiating treatment with moderate-efficacy DMTs and subsequently, escalating to higher-efficacy DMTs when there is evidence of clinical and/or radiological breakthrough activity. Recent real-world studies suggest that initiation of high-efficacy DMTs from disease onset can improve long-term outcomes for RMS patients. In this article, we review different treatment strategies and discuss challenges associated with personalized therapy.

The Effect of Smoking on Long-term Gray Matter Atrophy and Clinical Disability in Patients with Relapsing-Remitting Multiple Sclerosis

Background and Objectives

The relationship between smoking, long-term brain atrophy, and clinical disability in patients with multiple sclerosis (MS) is unclear. Here, we assessed long-term effects of smoking by evaluating MRI and clinical outcome measures after 10 years in smoking and nonsmoking patients with relapsing-remitting MS (RRMS).

Methods

We included 85 treatment-naive patients with RRMS with recent inflammatory disease activity who participated in a 10-year follow-up visit after a multicenter clinical trial of 24 months. Smoking status was decided for each patient by 2 separate definitions: by serum cotinine levels measured regularly for the first 2 years of the follow-up (during the clinical trial) and by retrospective patient self-reporting. At the 10-year follow-up visit, clinical tests were repeated, and brain atrophy measures were obtained from MRI using FreeSurfer. Differences in clinical and MRI measurements at the 10-year follow-up between smokers and nonsmokers were investigated by 2-sample t tests or Mann-Whitney tests and linear mixed-effect regression models. All analyses were conducted separately for each definition of smoking status.

Results

After 10 years, smoking (defined by serum cotinine levels) was associated with lower total white matter volume (β = −21.74, p = 0.039) and higher logT2 lesion volume (β = 0.22, p = 0.011). When defining smoking status by patient self-reporting, the repeated analyses found an additional association with lower deep gray matter volume (β = −2.35, p = 0.049), and smoking was also associated with a higher score (higher walking impairment) on the log timed 25-foot walk test (β = 0.050, p = 0.039) after 10 years and a larger decrease in paced auditory serial addition test (attention) scores (β = −3.58, p = 0.029).

Discussion

Smoking was associated with brain atrophy and disability progression 10 years later in patients with RRMS. The findings imply that patients should be advised and offered aid in smoking cessation shortly after diagnosis, to prevent long-term disability progression.

Epidemiology and Pathophysiology of Multiple Sclerosis

PURPOSE OF REVIEW

This article provides an overview of genetic, environmental, and lifestyle risk factors affecting the disease course of multiple sclerosis (MS) and reviews the pathophysiologic characteristics of both relapsing and progressive MS.

RECENT FINDINGS

The prevalence of MS has increased in recent decades, and costs of care for patients with MS have risen dramatically. Black, Asian, and Hispanic individuals may be at risk for more severe MS-related disability. Multiple genetic MS risk factors have been identified. Factors such as low vitamin D levels and a history of Epstein-Barr virus, smoking, and obesity, especially during childhood, also influence MS risk. Traditionally thought to be a T-cell-mediated disease, recent research has highlighted the additional roles of B cells and microglia in both relapsing and progressive MS.

SUMMARY

Complex interactions between genetic, environmental, and lifestyle factors affect the risk for MS as well as the disease course. People of color have historically been underrepresented in both MS clinical trials and literature, but current research is attempting to better clarify unique considerations in these groups. MS pathology consists of the focal inflammatory lesions that have been well characterized in relapsing MS, as well as a more widespread neurodegenerative component that is posited to drive progressive disease. Recent advances in characterization of both the inflammatory and neurodegenerative aspects of MS pathophysiology have yielded potential targets for future therapeutic options.

Smoking habits, awareness and support needs for cessation among people with multiple sclerosis in Australia: findings from an online survey

OBJECTIVES

To assess smoking habits, nicotine use, exposure to passive smoking, awareness of associated harms, and experiences with and preferences for smoking cessation support among people with multiple sclerosis (MS).

DESIGN

Online survey, convenience sampling.

SETTING

Community setting, Australia.

PARTICIPANTS

Adults living in Australia with probable or diagnosed MS were recruited via social media and newsletters to participate in 2020.

RESULTS

Of the 284 participants in our convenience sample, 25.7% were current smokers (n=73) and 38.0% were former smokers (n=108). Awareness of the harms of smoking on MS onset (n=68, 24.3%) and progression (n=116, 41.6%) was low. Almost a quarter (n=67, 23.8%) of participants were regularly exposed to passive smoke, and awareness of associated harm was also low (n=47, 16.8%). Among current smokers, 76.1% (n=54) had tried quitting and 73.2% considered quitting within 6 months (n=52). Many participants reported perceived short-term benefits of smoking, and long-term benefits of quitting, on MS symptoms and general well-being (short-term n=28, 40.0%; long-term n=28, 82.4%). While most participants reported that their neurologist (n=126, 75.4%) or other healthcare providers (n=125, 74.9%) had assessed smoking status, very few neurologists (n=3, 1.8%) or other healthcare providers (n=14, 8.4%) had provided help with quitting. Most current smokers preferred speaking about smoking to a neurologist (n=36, 52.2%) or general practitioner (n=41, 59.4%). Almost 60% of the current smokers wanted additional cessation information specific to MS (n=41, 59.4%), and 45.5% said this information would motivate them to quit smoking (n=30).

CONCLUSIONS

Our convenience sample, which may not be representative, indicated an urgent need for regular evidence-based smoking cessation supports for people with MS. Most participants felt they would benefit from smoking cessation advice. MS clinicians, in collaboration with patient organisations, smoking cessation services and general practitioners, should make smoking cessation promotion with people with MS a priority.

Associations between smoking and walking, fatigue, depression, and health-related quality of life in persons with multiple sclerosis

Smoking is associated with increased multiple sclerosis (MS) risk. In addition, some studies have reported that smoking is associated with anxiety and depression. However, the associations between smoking, walking, and fatigue are needed to be investigated. The objective was to investigate the associations between cigarette smoking and walking, fatigue, depression symptom severity, and health-related quality of life in persons with MS. Two hundred seventy-nine persons with MS were evaluated in this cross-sectional study. Study outcomes were neurological disability level, walking speed, walking endurance, perceived walking impact of MS, fatigue, depression symptom severity, and health-related quality of life. There were 95 (34.1%) current smokers who had significantly higher fatigue (p = 0.003, pη² = 0.031) and depression (p = 0.044, pη² = 0.015), and lower health-related quality of life (p = 0.003, pη² = 0.031) after adjusting for age, gender, neurological disability level, and disease duration compared to non-smokers (n = 184). There was no significant difference between smokers and non-smokers in walking measures (p > 0.05). Smoking intensity was significantly correlated with age (r = 0.487), neurological disability level (r = 0.227), disease duration (r = 0.30), walking speed (r = 0.574), walking endurance (r =  - 0.461), perceived walking impact of MS (r = 0.684), fatigue (r = 0.370), health-related quality of life (r =  - 0.259), and depression (r = 0.269) in current smokers. Cigarette smokers with MS had significantly more fatigue and depression symptom severity and less health-related quality of life compared to non-smokers. Increased pack-years of cigarette smoking was associated with worse walking ability and health-related quality of life, and greater depression symptom severity and fatigue.

Prediction in treatment outcomes in multiple sclerosis: challenges and recent advances

INTRODUCTION

Multiple Sclerosis (MS) is a chronic autoimmune and neurodegenerative disease of the central nervous system with a course dependent on early treatment response. Increasing evidence also suggests that despite eliminating disease activity (relapses and lesions), many patients continue to accrue disability, highlighting the need for a more comprehensive definition of treatment success. Optimizing disability outcome measures, as well as continuously improving our understanding of neuroinflammatory and neurodegenerative biomarkers is required.

AREAS COVERED

This review describes the challenges inherent in classifying and monitoring disease phenotype in MS. The review also provides an assessment of clinical, radiological, and blood biomarker tools for current and future practice.

EXPERT OPINION

Emerging MRI techniques and standardized patient outcome assessments will increase the accuracy of initial diagnosis and understanding of disease progression.

Role of environmental factors in multiple sclerosis

INTRODUCTION

Environmental factors play a significant role in the pathogenesis and progression of multiple sclerosis (MS), either acting alone or by interacting with other environmental or genetic factors. This cumulative exposure to external risk factors is highly complex and highly variable between individuals.

AREAS COVERED

We narratively review the current evidence on the role of environment-specific risk factors in MS onset and progression, as well as the effect of gene-environment interactions and the timing of exposure We have reviewed the latest literature, by Ovid Medline, retrieving the most recently published systematic reviews and/or meta-analyses and more recent studies not previously included in meta-analyses or systematic reviews.

EXPERT OPINION

There is some good evidence supporting the impact of some environmental risk factors in increasing the risk of developing MS. Tobacco smoking, low vitamin D levels and/or low sun exposure, Epstein Barr Virus (EBV) seropositivity and a history of infectious mononucleosis may increase the risk of developing MS. Additionally, there is some evidence that gene-smoking, gene-EBV, and smoking-EBV interactions additively affect the risk of MS onset. However, the evidence for a role of other environmental factors in MS progression is limited. Finally, there is some evidence that tobacco smoking, insufficient vitamin D levels and/or sun exposure have impacts on MS phenotypes and various markers of disease activity including relapse, disability progression and MRI findings. Clearly the effect of environmental factors on MS disease course is an area that requires significantly more research.

Exploring polypharmacy phenomenon in newly diagnosed relapsing-remitting multiple sclerosis: a cohort ambispective single-centre study

Aims:

We aimed to examine the frequency of polypharmacy in a large cohort of patients at the time of diagnosis of relapsing–remitting multiple sclerosis (RRMS) and to explore its effects on discontinuation of first disease-modifying treatment (DMT) using survival analysis.

Methods:

This was a cohort ambispective single-centre study. We enrolled RRMS patients starting their first DMT between 1st January 2013 and 31st December 2015. According to the number of medicines prescribed (except DMTs), we divided the patients into three groups: no-poly RRMS, minor-poly RRMS (from one to three medications), and major-poly RRMS (more than three medications).

Results:

A total of 392 RRMS patients were enrolled (mean age 41.1). The minor-poly RRMS group included 61 patients (15.6%) and the major-poly RRMS group included 112 (28.6%). Individuals in these groups were older and had higher median body mass index (BMI) than patients in the no-poly RRMS group (p < 0.05). Upon multinomial regression analysis, older age at onset was associated with minor and major polypharmacy (OR 1.050, CI 1.010–1.093, p = 0.015 and OR 1.063, CI 1.026–1.101, p = 0.001, respectively) and higher BMI was associated with major polypharmacy (OR 1.186, CI 1.18–1.29, p = 0.001). The rates of discontinuation of first DMT were similar among the three groups (50.7% for no-Poly RRMS, 50.8% for minor-Poly RRMS, and 53.3% for major-Poly RRMS, p = 0.264). At log-Rank test, there were no differences among the three groups (p = 0.834).

Conclusion:

Polypharmacy was more common in older RRMS patients with high BMI.

Considering patient age when treating multiple sclerosis across the adult lifespan

Introduction: The successful development of anti-inflammatory disease-modifying treatments (DMT) significantly improved disease outcomes and longevity of persons with multiple sclerosis (pwMS). However, the shift toward an elderly MS population has resulted with new concerns regarding DMT efficacy and safety.Areas covered: This review summarizes the evidence of an age-based decrease in the efficacy of MS DMTs and increase in pharmacovigilance concerns. The age effects on pathophysiological MS processes, immunosenescence and its relevance to DMT selection or discontinuation are also reviewed. Lastly, the authors discuss the influence of age-associated comorbidities on DMT initiation and drug-induced events.Expert opinion: There is an age discrepancy between pwMS included in regulatory drug trials and an aging real-world MS population. Most trials demonstrate significantly diminished anti-inflammatory efficacy in patients older than 40 years old. Older age is associated with a greater risk for adverse events including serious infections. Age-associated comorbidities influence the risk-benefit analysis and sometimes cause patients to discontinue DMTs. Instead of chronological age cutoffs, therefore, studies should aim at promoting biologically-based age biomarkers.

The influence of smoking on the pattern of disability and relapse risk in AQP4-positive Neuromyelitis Optica Spectrum Disorder, MOG-Ab Disease and Multiple Sclerosis

BACKGROUND

the role of smoking on clinical outcomes of central nervous system (CNS) inflammatory disorders is unclear. To assess the effect of smoking on relapses and disability in neuromyelitis optica with aquaporin-4-antibodies (NMOSD-AQP4-Ab), Myelin Oligodendrocyte Glycoprotein-antibodies associated disease (MOGAD) and relapsing remitting Multiple Sclerosis (MS) patients.

METHODS

in a UK cohort of 101 NMOSD-AQP4-Ab, 70 MOGAD and 159 MS, and a Korean cohort of 97 NMOSD-AQ4-Ab, time to first relapse, annualised relapse rate, onset relapse severity and recovery, time to Expanded Disability Status Score(EDSS)/secondary progressive MS (SPMS) were compared between never-smokers and ever-smokers. All clinical data were collected under the local ethics between January 2017 and January 2019.

RESULTS

Smoking did not affect the risk of relapse in any of the diseases. The risk of reaching EDSS 6.0 in the UK NMOSD-AQP4-Ab cohort was higher in ever smokers but this did not achieve significance (HR 2.12, p=0.068). When combining the UK and Korea NMOSD-AQP4-Ab cohorts, poorer recovery from the onset attack was significantly more frequent in the ever-smokers versus the never smokers (55% vs 38%, p=0.04). In the MS cohort the risk of reaching EDSS 6 and SPMS was significantly higher in the ever-smokers (HR=2.67, p=0.01 and HR=3.18, p=0.001). In MOGAD similar patterns were seen without reaching significance.

CONCLUSIONS

In NMOSD-AQP4-Ab smoking associates with worse disability not through an increased risk of relapses but through poor relapse recovery. As in MS, smoking cessation should be encouraged in NMOSD-AQP4-Ab.

Effect of tobacco use on disease activity and DMT discontinuation in multiple sclerosis patients treated with dimethyl fumarate or fingolimod

Background

Tobacco exposure is a modifiable risk factor for multiple sclerosis (MS). Studies evaluating the relationship between tobacco, disease activity, and disease modifying therapy (DMT) persistence yielded conflicting results. We sought to address this issue with data from clinical practice.

Objective

To compare 24-month disease outcomes in tobacco versus non-tobacco users treated with dimethyl fumarate (DMF) or fingolimod (FTY) in clinical practice.

Methods

We retrospectively identified 659 MS patients treated with DMF or FTY, stratified by patient-reported tobacco use. DMT discontinuation and measures of disease activity at 24 months were assessed using propensity score (PS) weighting. Outcome estimates were calculated as tobacco vs non-tobacco use.

Results

164 tobacco users (DMF n = 101; FTY n = 63) and 495 non-tobacco users (DMF n = 294; FTY n = 201) were identified. Tobacco (39.4%) and non-tobacco (34.4%) users were equally likely to discontinue DMT (OR = 1.17, 95% CI 0.79, 1.75), but tobacco users discontinued therapy earlier (HR = 1.53, 95% CI 1.06, 2.43). There were no differences in ARR (rate ratio = 1.39, 95% CI 0.97, 1.96). However, tobacco users had decreased odds of NEDA-2 (OR = 0.61, 95% CI 0.44, 0.83).

Conclusion

Our findings suggest that tobacco is a negative risk factor for inflammatory disease activity and earlier DMF and FTY discontinuation.

The impact of tobacco smoking on treatment choice and efficacy in inflammatory bowel disease

Smoking significantly increases the risk of developing and worsens Crohn's disease (CD), yet protects against the development and reduces the severity of ulcerative colitis. It is less clear whether smoking impacts the efficacy of therapeutics in inflammatory bowel disease (IBD). We review the literature regarding the relationship between smoking and the efficacy of medical and surgical therapy in IBD. Smoking is associated with alterations in thiopurine metabolism and may affect time to disease relapse. The outcomes of anti-tumor necrosis factor therapy in active smokers appear neutral with data lacking for newer biologics. Smoking increases the risk of postoperative recurrence in those requiring resection for CD, likely attributable to perturbations of the gut microbiota although further implications of these for disease onset/progression and treatment efficacy remain unclear. Multiple lifestyle and psychosocial confounders are likely under-recognized cofactors in the association between smoking and IBD. Despite the widely promulgated risks associated with cigarette smoking in CD, more incisive data are required to further elucidate the actual relationship between smoking and disease pathways, while accounting for the several negative cofactors prevalent in smokers which cast uncertainty on the magnitude of the direct effect of smoking on disease pathophysiology and the efficacy of therapy.

Comorbidity in Multiple Sclerosis

Comorbidities in patients with multiple sclerosis (MS) has become an area of increasing interest in the recent years. A comorbidity is defined as any additional disease that coexists in an individual with a given index disease and that is not an obvious complication of the index disease. The aim of this review is to describe the current evidence regarding the range of comorbidities in the population with MS reported in different countries and the current knowledge about the influence of comorbidities on the clinical features and therapeutic challenges in MS. Certain comorbidities are more prevalent in people with MS such as depression, anxiety, cerebro- and cardiovascular diseases, and certain autoimmune disorders such as diabetes, thyroid disease, and inflammatory bowel disease. A previous perception of a trend toward a lower overall risk of cancer in patients with MS appears to be challenged, but there is no evidence on any higher occurrence of malignancies in the population with MS. Comorbidities may modify the clinical presentation of MS, and have implications for treatment choice, adherence, and outcome. Several comorbid conditions are associated with increased disability progression, including diabetes, hypertension, and chronic obstructive pulmonary disease. Comorbidities are common in MS from the time of diagnosis and may account for some of the heterogeneity observed in MS, including diagnostic delay, clinical presentation, degree of disability progression, rate of health care utilization, working ability, employment status, and quality of life. Coexisting diseases and polypharmacy increase the complexity of patient management and poses major challenges, particularly with the increasing number of immunosuppressive disease-modifying therapies.

Long-term drug treatment in multiple sclerosis: safety success and concerns

INTRODUCTION

The portfolio of multiple sclerosis (MS) disease modifying treatments (DMTs) has significantly expanded over the past two decades. Given the lifelong use of MS pharmacotherapy, understanding their long-term safety profiles is essential in determining suitable and personalized treatment.

AREAS COVERED

In this narrative review, we summarize the short-, mid-, and long-term safety profile of currently available MS DMTs categories. In addition to the initial trial findings, safety outcomes derived from long-term extension studies (≥5-20 years) and safety-based prescription programs have been reviewed. In order to better understand the risk-benefit ratio for each particular DMT group, a short description of the DMT-based efficacy outcomes has been included.

EXPERT OPINION

Long-term extension trials, large observational studies and real-world databases allow detection of rare and potentially serious adverse events. Two-year-long trials are unable to fully capture the positive and negative effects of immune system modulation and reconstitution. DMT-based monitoring programs can provide greater insights regarding safe use of MS medications in different patient populations and clinical settings. During the process of shared DMT decision, both MS care providers and their patients should be aware of an ever-expanding number of drug-based adverse events and their influence on the risk-benefit analysis.

The apparently milder course of multiple sclerosis: changes in the diagnostic criteria, therapy and natural history

In the past decade, changes have occurred in the spectrum of multiple sclerosis courses. The natural history of multiple sclerosis appears milder from the first sign of demyelinating disease to the progressive course, probably as a result of an interplay between several factors including changes in the diagnostic criteria, changes in the epidemiology of multiple sclerosis, impact of early and appropriate disease-modifying treatment and improvement of the general state of health in the population. It has been suggested to regard incidental findings of demyelinating lesions in MRI in individuals without any history of clinical symptoms consistent with neurological dysfunction, so-called radiological isolated syndrome, as the initial course of multiple sclerosis. New diagnostic criteria have enabled the multiple sclerosis diagnosis in many patients at the first clinical demyelinating event, clinically isolated syndrome. The remaining patients with clinically isolated syndrome have a more benign prognosis, and for relapsing-remitting multiple sclerosis, the prognosis has become more favourable. Reduced disease activity in patients with relapsing-remitting multiple sclerosis can partly be ascribed to more efficacious new disease-modifying therapies but decrease in disease activity has also be seen in placebo-treated patients in clinical trials. This may be explained by several factors: change in the diagnostic criteria, more explicit inclusion criteria, exclusion of high-risk patients e.g. patients with co-morbidities, and more rigorous definitions of relapses and disease worsening. However, these factors also make the disease course in patients treated with disease-modifying therapies seem more favourable. In addition, change in the therapeutic target to stable disease (no evidence of disease activity = no relapses, no disease worsening and no MRI activity) could by itself change the course in relapsing-remitting multiple sclerosis. The effectiveness of disease-modifying drugs has reduced the transition from relapsing-remitting to secondary progressive multiple sclerosis. The concept of progressive multiple sclerosis has also evolved from two very distinct categories (primary progressive and secondary progressive multiple sclerosis) to a unified category of progressive multiple sclerosis, which can then be split into the categories of active or inactive. Also, an increasing tendency to treat progressive multiple sclerosis with disease-modifying therapies may have contributed to change the course in progressive multiple sclerosis. In conclusion, during the past decade the entire course of multiple sclerosis from the first sign of a demyelinating disorder through the progressive course appears to be milder due to a complex interplay of several factors.

Comorbidity is associated with disease activity in MS: Findings from the CombiRx trial

OBJECTIVE

To determine whether comorbidity is associated with clinical (relapses, disability worsening) and MRI outcomes in multiple sclerosis (MS) by conducting a secondary analysis of the CombiRx clinical trial.

METHODS

CombiRx compared interferon beta-1a, glatiramer acetate, and the combination of these agents. For participants eligible for evaluation of 6-month confirmed disability worsening, we used medical history, concomitant medications, and adverse events to ascertain comorbidity status. Comorbid conditions evaluated included hypertension, dyslipidemia, diabetes mellitus, depression, anxiety disorders, and migraine. Clinical outcomes included disease activity consisting of protocol-defined relapses, disability worsening, and MRI activity. We summarized the prevalence of these comorbid conditions and their association with disease activity and its components using multivariable Cox regression.

RESULTS

Of the 1,008 participants randomized, 959 (95.1%) were eligible for assessment of 6-month disability worsening; for this subgroup, the median length of follow-up was 3.4 years (range 0.5-6.9 years). Overall, 55.1% of participants had ≥1 comorbidity at enrollment. After adjustment, anxiety (hazard ratio [HR] 1.25, 95% confidence interval [CI] 1.01-1.55) and dyslipidemia (HR 1.32, 95% CI 1.01-1.72) were associated with an increased hazard of any disease activity, while migraine (HR 0.80, 95% CI 0.67-0.97) was associated with a decreased hazard.

CONCLUSIONS

In this large trial population with rigorously obtained outcomes, comorbid conditions were common among participants and influenced disease outcomes, including relapses. The comorbidity burden of clinical trial participants with MS may be an important factor in the outcome of clinical trials. Additional investigations of the impact of comorbidity on clinical trial outcomes and response to disease-modifying therapies are warranted.

Duration of natalizumab therapy and reasons for discontinuation in a multiple sclerosis population

Objective

To determine multiple sclerosis patient characteristics that predict a shorter duration of natalizumab treatment.

Methods

The Tysabri Outreach: Unified Commitment to Health database was reviewed to identify patients treated with natalizumab at our centers. Cox proportional hazards models were used to evaluate patient characteristics associated with shorter treatment durations on natalizumab. Associations were also assessed with respect to specific reasons for stopping natalizumab.

Results

We identified 554 patients who began and stopped natalizumab treatment during the observation period. The average disease duration at natalizumab initiation was 7.6 years, and the average number of infusions was 30. The multivariable Cox proportional hazards model identified greater age (P = 0.035), longer disease duration (P < 0.001), progressive relapsing multiple sclerosis phenotype (P = 0.003), current smoking (P = 0.031), and greater depression (P = 0.026) as significant predictors for natalizumab discontinuation. Greater disability levels (P = 0.022) and gadolinium-enhancing lesions on baseline magnetic resonance imaging (P < 0.001) were significantly associated with longer natalizumab treatment. Individuals with progressive relapsing multiple sclerosis had a 14-fold increased hazard of discontinuing natalizumab due to inflammatory events (P < 0.001) than those with relapsing–remitting multiple sclerosis. Smokers had an 80% increased hazard of discontinuation due to intolerance (P = 0.008).

Conclusions

Our results suggest that smoking, depression, and a progressive relapsing multiple sclerosis phenotype are associated with shorter natalizumab treatment durations.

Vascular aspects of multiple sclerosis: emphasis on perfusion and cardiovascular comorbidities

INTRODUCTION

Multiple sclerosis (MS) is a chronic inflammatory, demyelinating, and neurodegenerative disease of the central nervous system. Over the last two decades, more favorable MS long-term outcomes have contributed toward increase in prevalence of the aged MS population. Emergence of age-associated pathology, such as cardiovascular diseases, may interact with the MS pathophysiology and further contribute to disease progression. Areas covered: This review summarizes the cardiovascular involvement in MS pathology, its disease activity, and progression. The cardiovascular health, the presence of various cardiovascular diseases, and their effect on MS cognitive performance are further explored. In similar fashion, the emerging evidence of a higher incidence of extracranial arterial pathology and its association with brain MS pathology are discussed. Finally, the authors outline the methodologies behind specific perfusion magnetic resonance imaging (MRI) and ultrasound Doppler techniques, which allow measurement of disease-specific and age-specific vascular changes in the aging population and MS patients. Expert opinion: Cardiovascular pathology significantly contributes to worse clinical and MRI-derived disease outcomes in MS. Global and regional cerebral hypoperfusion may be associated with poorer physical and cognitive performance. Prevention, improved detection, and treatment of the cardiovascular-based pathology may improve the overall long-term health of MS patients.