Smoking rates and smoking cessation among individuals with multiple sclerosis

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.

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.

Barriers and motivators for tobacco smoking cessation in people with multiple sclerosis

INTRODUCTION

Smoking is a key modifiable risk factor for health outcomes of people with multiple sclerosis (MS). Little evidence exists on whether the information and support needs of people with MS who smoke are met. This study aimed to explore knowledge, attitudes and beliefs about smoking and quitting, and quitting support needs in Australian people with MS.

METHODS

Current and recent smokers were recruited for phone interviews through social media and newsletters. Interview data were analysed in NVivo using framework analysis.

RESULTS

We interviewed 25 people with MS (20 current and five recent smokers). Many participants had little knowledge about the risks of smoking on MS progression. Some reported perceived benefits from smoking on MS symptoms, while others perceived smoking worsening their symptoms. Similarly, quitting was believed to have health benefits, but concerns about withdrawal symptoms and the impact on MS symptoms and relapses were common. Participants reported ambivalence discussing smoking with clinicians; some wanting more information and support, while also feeling shame or guilt. Many participants were asked about their smoking status by MS clinicians, however, the provision of evidence-based information, and referrals to quitting support services was very infrequent. General practitioners were often found helpful and supportive, but participants gave more weight to quit advice from MS clinicians.

CONCLUSION

Our results are the first to indicate that smoking cessation needs of Australian people with MS are not met. These findings should be confirmed in a larger sample, but there is potential to investigate whether implementing routine provision of brief advice in MS care, as a coordinated effort between MS researchers, practitioners, consumer advocates and behavioural intervention services, may meet these needs. Further, developing targeted resources and training quit counsellors to provide appropriate information and support specific to people with MS may improve smoking cessation success in people with MS.

Facebook usage, participation patterns, and social support from Facebook activity among smokers with mobility impairments

People with mobility impairments (MIs; use assistive devices to ambulate) have twice the smoking prevalence versus the general population. A Facebook intervention could improve reach to smokers with MIs, but use and patterns of use are unknown. The study examined: (a) Facebook use and relationship with Facebook-based social support and (b) whether Facebook use differs by motivation to quit smoking. Participants (N = 510; 56.3% female, mean age = 42.4 years) were recruited via a recruitment company to complete a one-time online survey assessing motivation to quit within 30 days, Facebook use (Facebook Activities Scale), reasons for use (Facebook Motives Scale), attitudes (Facebook Intensity Scale), and social support (Facebook Measure of Social Support). The vast majority said that Facebook is part of their daily routine (92.9%), 83% checked Facebook >once a day, and 69% spent >30 min/day on Facebook. Facebook was used to connect with similar others (68.4%), participate in groups (72.9%), decrease loneliness (69.2%), and obtain health information (62.5%); 88% said that they would join a Facebook program to help them quit smoking. A greater number of Facebook friends (rs = .18-.22, p < .001) and greater Facebook use (rs = .20 to rs = .59; p < .001) were correlated with greater perceived social and emotional support. Those motivated to quit posted more frequently (odds ratio [OR] = 1.56, 95% confidence interval [CI] = 1.10, 2.22) and were more likely to indicate that they would join a Facebook group for smoking cessation (OR = 4.15, 95% CI = 2.05, 8.38) than those not motivated. Facebook could circumvent disability and environmental barriers to accessing cessation among this health disparity population.

Environmental and Nutritional "Stressors" and Oligodendrocyte Dysfunction: Role of Mitochondrial and Endoplasmatic Reticulum Impairment

Oligodendrocytes are myelinating cells of the central nervous system which are generated by progenitor oligodendrocytes as a result of maturation processes. The main function of mature oligodendrocytes is to produce myelin, a lipid-rich multi-lamellar membrane that wraps tightly around neuronal axons, insulating them and facilitating nerve conduction through saltatory propagation. The myelination process requires the consumption a large amount of energy and a high metabolic turnover. Mitochondria are essential organelles which regulate many cellular functions, including energy production through oxidative phosphorylation. Any mitochondrial dysfunction impacts cellular metabolism and negatively affects the health of the organism. If the functioning of the mitochondria is unbalanced, the myelination process is impaired. When myelination has finished, oligodendrocyte will have synthesized about 40% of the total lipids present in the brain. Since lipid synthesis occurs in the cellular endoplasmic reticulum, the dysfunction of this organelle can lead to partial or deficient myelination, triggering numerous neurodegenerative diseases. In this review, the induced malfunction of oligodendrocytes by harmful exogenous stimuli has been outlined. In particular, the effects of alcohol consumption and heavy metal intake are discussed. Furthermore, the response of the oligodendrocyte to excessive mitochondrial oxidative stress and to the altered regulation of the functioning of the endoplasmic reticulum will be explored.

Smoking Cessation and the Reduction of Disability Progression in Multiple Sclerosis: A Cohort Study

Background

Smoking is associated with a more severe disease course in people with multiple sclerosis (MS). The magnitude of effect of smoking cessation on MS progression is unknown. The aim of this study was to quantify the impact of smoking cessation on reaching MS disability milestones.

Aims and Methods

This is a cross-sectional study with retrospective reports. A comprehensive smoking questionnaire was sent to 1270 patients with MS registered between 1994 and 2013 in the Nottingham University Hospital MS Clinics database. Demographic and clinical data were extracted from the clinical database. Cox proportional hazard regression was used to estimate effects of smoke-free years on the time to Expanded Disability Status Scale (EDSS) scores 4.0 and 6.0. MS Impact Scale 29 and Patient Determined Disease Steps were used to assess the physical and psychological impact of smoking.

Results

Each "smoke-free year" was associated with 0.96 (95% confidence interval: 0.95 to 0.97) times decreased risk of reaching EDSS 4.0 and 0.97 (95% confidence interval: 0.95 to 0.98) times decreased risk of reaching EDSS 6.0. Nonsmokers showed a significantly lower level of disability in all the self-reported outcomes compared with current smokers.

Conclusions

The reduction in the risk of disability progression after smoking cessation is significant and time dependent. The earlier the patients quit, the stronger the reduction in the risk of reaching disability milestones. The quantitative estimates of the impact of smoking cessation on reaching disability milestones in MS can be used in interventional trials.

Implications

This study provides for the first time quantitative estimates of the effects of smoking cessation in MS, essential for informing smoking cessation trials. The clear effect of smoking cessation on MS progression suggests the need to consider adjusting for smoking cessation when assessing for treatment effects in clinical trials of treatments for MS. Smoking cessation should be an early intervention in people with MS.

Modifiable risk factors for poor health outcomes in multiple sclerosis: The urgent need for research to maximise smoking cessation success

Tobacco smoking is a well-established risk factor for multiple sclerosis (MS) onset, progression and poor health outcomes in people with MS. Despite smoking being a modifiable risk factor, no research has been undertaken to understand how, or who is best placed, to assess or understand smoking behaviour in people with MS, or how healthcare professionals can best assist people with MS to quit. People with MS may have unique motivators to continue smoking, or unique barriers to smoking cessation, that are not addressed by existing cessation tools. Research is urgently needed in this area if the aim is to maximise health outcomes for all people with MS.

Understanding barriers, enablers, and long-term adherence to a health behavior intervention in people with multiple sclerosis

Background: The optimal management strategy for multiple sclerosis (MS), and many other chronic diseases, likely involves health behavior modification. Multimodal behavioral interventions may be most effective, but little is known about long-term adherence in people with MS.Methods: This qualitative study assessed barriers and enablers to long-term adherence by people with MS who self-selected for a 5-day health behavior intervention 3-5 years prior. Thirteen women and five men participated in semi-structured phone interviews, which were transcribed and thematically analyzed.Results: The experience was described as useful for information gathering, decision making, and practical strategies regarding health behaviors. The majority still followed supplementation and dietary recommendations most of the time, although consuming non-recommended food while eating out was common. Support at home, ability and enjoyment in food preparation, and ability to resist unhealthy foods were both barriers and enablers. Adherence to "time-consuming" exercise and meditation recommendations were less common and episodic. Many reported competing interests on time from work and family; and barriers including injuries and symptoms, weather, financial or geographical barriers, and lack of person-centred support and motivation. Increased fitness and mobility, weight loss, and a sense of accomplishment and control were advantages and motivators. Practical and attitudinal strategies employed included planning, tailoring activities to ability and preference, and self-monitoring.Conclusion: While most people attempted to engage with all components of the intervention initially, only some still engaged with all components, and none to the recommended levels. These data can inform future quantitative studies and health behavior interventions.Implications for rehabilitationA multimodal group lifestyle intervention may be useful to assist people with multiple sclerosis in information gathering, decision making, attitudinal changes, and practical strategies regarding health behaviors; as well as providing a sense of hope for the future and control over wellbeing.While participants are unlikely to engage with all components of a multimodal intervention to the recommended level, they are likely to make improvements to one or more health behaviors.Experiential learning, including going through recipes and ingredient lists, and practicing meditation and physical exercises, is helpful to instigate behavior change.The initiation and maintenance of behavior change was assisted by support from family, friends, and health practitioners; and practical strategies employed by participants, including planning, self-monitoring, and tailoring activities to ability and preference.

Smokers with MS have greater decrements in quality of life and disability than non-smokers

BACKGROUND

Tobacco smoke plays a pathogenic role in multiple sclerosis (MS) and may accelerate disease progression, yet, some people with MS continue to smoke after disease onset. The average smoker reports diminished health-related quality of life (HRQOL) across many populations.

OBJECTIVES

To describe the relationships between smoking status and HRQOL, disease activity, and global disability in a US population with MS.

METHODS

We compared smokers to non-smokers in 950 responders to the Spring 2014 update survey completed by North American Research Committee on Multiple Sclerosis (NARCOMS) registry participants. HRQOL was assessed using Short Form-12 version 2 (SF-12v2), disease activity was investigated using eight Performance Scales (PS) and three Functionality Scales (FS). Global disability was evaluated using Patient Determined Disease Steps (PDDS) and an item response theory (IRT) summed score based on the PS and FS.

RESULTS

Smokers had lower HRQOL ( p < 0.0001), reported more disease activity ( p < 0.05) and greater deficits in all PS and FS ( p = 6 × 10^-7 to 0.05), except mobility. Smokers and non-smokers did not differ by PDDS but had substantially greater IRT global disability ( p = 2 × 10^-7).

CONCLUSION

Active smoking is meaningfully associated with deficits across multiple domains in people with MS and adds to the growing literature of the need for MS-tailored smoking cessation programs.

Individual and Co-occurring SNAP Risk Factors: Smoking, Nutrition, Alcohol Consumption, and Physical Activity in People with Multiple Sclerosis

Background: Smoking, poor nutrition, excess alcohol consumption, and insufficient physical activity underlie most preventable causes of morbidity in the general population and may be associated with comorbidities and health outcomes in multiple sclerosis (MS). However, the frequency of co-occurrence of these risk factors in people with MS remains unclear. Methods: Sixty-nine individuals with MS completed self-report measures of smoking status, nutrition, alcohol use, physical activity levels, and sociodemographic and clinical characteristics. The data were analyzed using t tests and χ² analyses. Results: Poor diet was the most common risk factor, with 85.5% of the sample not meeting dietary guidelines. Of participants with two risk factors, 90.3% were not meeting dietary and physical activity guidelines. Seventy-three percent of women were not meeting physical activity guidelines, compared with 38% of men (χ² = 7.5, P < .01). There were also differential rates by sex of the most commonly co-occurring risk factors: 65% of women reported the co-occurrence of insufficient physical activity and poor diet, compared with 38% of men (χ² = 4.2, P = .05). Conclusions: These results indicate that 85.5% of the sample was not meeting nutrition guidelines, 90.3% of participants with two risk factors reported the co-occurrence of poor diet and insufficient levels of physical activity, and physical activity levels and the total number of risk factors varied across sex.

What role does tobacco smoking play in multiple sclerosis disability and mortality? A review of the evidence

There is increasing evidence of tobacco smoking as an associative factor in multiple sclerosis (MS). Numerous studies have been conducted investigating the effects of smoking before the onset of MS as well as its impact on disease course. This special report reviews the available evidence and summarizes the contribution of smoking to increased mortality in patients with MS. It also explores some putative mechanisms for the involvement of tobacco constituents in the pathology of MS and the effects of smoking on disease-modifying treatments.

Acute systemic accumulation of acrolein in mice by inhalation at a concentration similar to that in cigarette smoke

Cigarette smoke is an important environmental factor associated with a wide array of public health concerns. Acrolein, a component of tobacco smoke and a known toxin to various cell types, may be a key pathological factor mediating the adverse effects linked with tobacco smoke. Although acrolein is known to accumulate in the respiratory system after acute nasal exposure, it is not clear if it accumulates systemically, and less is known in the nervous system. The aim of this study was to assess the degree of acrolein accumulation in the circulation and in the spinal cord following acute acrolein inhalation in mice. Using a laboratory-fabricated inhalation chamber, we found elevated urinary 3-HPMA, an acrolein metabolite, and increased acrolein adducts in the spinal cord after weeks of nasal exposure to acrolein at a concentration similar to that in tobacco smoke. The data indicated that acrolein is absorbed into the circulatory system and some enters the nervous system. It is expected that these findings may facilitate further studies to probe the pathological role of acrolein in the nervous system resulting from smoke and other external sources.

Association between smoking and cognitive impairment in multiple sclerosis

PURPOSE

Although smoking is known to cause various symptoms in multiple sclerosis (MS) patients, there have been no reports regarding the relationship between smoking and cognitive impairment in MS. Studying the effects of cigarette smoking in MS patients is imperative as there is a high prevalence of cognitive impairment in MS patients. In this study we examined the potentially deleterious effects of heavy smoking on mentation of patients with MS.

PATIENTS AND METHODS

MS patients receiving care at the Neurology Clinic at Bezmialem Vakıf University, between the ages of 18-65 years who have at least graduated elementary school were included in the study. The Brief Repeatable Battery of Neuropsychological Tests (BRB-N) is a commonly used method to assess cognitive function in MS patients and was utilized in our study. Patients that smoked for at least 10 pack-years were considered heavy smokers.

RESULTS

ALL THE PATIENTS WERE STRATIFIED INTO TWO GROUPS: heavy smokers (n=20) and nonsmokers (n=24). For heavy smokers, their cognitive functioning was more impaired than that of nonsmokers (P=0.04, χ (2)=4.227). For patients with cognitive impairment, 78.9% of the Paced Auditory Serial Addition Test and 63.2% of the Symbol Digit Modalities Test scores were found to be lower.

CONCLUSION

Previous reports have suggested that smoking increases the frequency of relapse among individuals with relapsing-remitting MS and accelerates disease progression in patients with progressive MS. According to the results of our study, heavy smokers had increased cognitive impairment when compared to nonsmokers. Extensive studies are necessary to further elucidate the relationship between smoking and cognitive impairment in MS patients.

Methods used to quit smoking by people with physical disabilities

PURPOSE/OBJECTIVE

People with mobility impairments (MIs) have higher smoking rates than the general population. We evaluated the use of psychosocial and pharmacological methods to quit smoking and readiness to quit smoking in this population in a cross-sectional study.

RESEARCH METHOD/DESIGN

Current and former smokers with MIs who needed equipment to ambulate (e.g., cane, wheelchair; n = 152, 53.3% female, 86.2% current smokers) were recruited from the community and interviewed by telephone regarding their lifetime use of various quit methods and readiness to quit smoking.

RESULTS

Results indicated that 57.3% reported a quit attempt in the past year, and 62% and 88.4% were planning on quitting in the next 30 days and six months, respectively. A minority of smokers with MIs reported using any type of counseling (5.3%; 3.3% in-person counseling and 2.6% phone counseling) or tablet medication (8.6%); 75% had made a "cold turkey" quit attempt (e.g., without any assistance). 36.8% and 19.7% reported using the nicotine patch and gum, respectively. Regression analyses indicated that greater nicotine dependence was associated with lower use of psychosocial treatments (p < .05), greater education was associated with greater tablet medication use (p = .051), and higher income was associated with both greater nicotine replacement therapy (NRT) and tablet medication use (p < .05). Minorities with MIs were significantly less likely to use NRT than non-Hispanic Whites (p < .05).

CONCLUSIONS

Individuals with MIs are motivated to quit smoking but underuse some empirically validated cessation treatment options.

Environmental risk factors for multiple sclerosis: a review with a focus on molecular mechanisms

Multiple sclerosis (MS) is a chronic disabling disease of the central nervous system commonly affecting young adults. Pathologically, there are patches of inflammation (plaques) with demyelination of axons and oligodendrocyte loss. There is a global latitude gradient in MS prevalence, and incidence of MS is increasing (particularly in females). These changes suggest a major role for environmental factors in causation of disease. We have reviewed the evidence and potential mechanisms of action for three exposures: vitamin D, Epstein Barr virus and cigarette smoking. Recent advances supporting gene-environment interactions are reviewed. Further research is needed to establish mechanisms of causality in humans and to explore preventative strategies.

Multiple sclerosis and risk of venous thromboembolism: a population-based cohort study

BACKGROUND

Multiple sclerosis (MS) patients may be at increased risk of venous thromboembolism (VTE), but evidence is limited.

OBJECTIVES

To examine long-term risk of VTE among MS patients.

PATIENTS AND METHODS

We conducted a population-based cohort study among 17,418 Danish MS patients and 87,090 comparison cohort members from the general population. Data on MS, VTE and comorbidities were obtained from the Danish National Registry of Patients including all admissions to Danish hospitals since 1977. We computed cumulative risks for VTE and adjusted incidence rate ratios (IRRs).

RESULTS

A total of 34 (0.2%) MS patients and 36 (0.04%) comparison cohort members had a deep venous thrombosis (DVT) within 1 year following the date of initial MS diagnosis/index date [adjusted IRR = 3.02 (95% CI: 2.14-4.27)]. During this period, 16 (0.09%) MS patients and 26 (0.03%) comparison cohort members had a documented pulmonary embolism (PE) [adjusted IRR = 2.85 (95% CI: 1.72-4.70)]. During the subsequent up to 29 years, 315 (1.9% of MS patients alive at year 1) MS patients had a record of a DVT [adjusted IRR = 2.28 (95% CI: 2.01-2.59)] and 129 (0.8%) had PE [IRR = 1.58 (95% CI: 1.31-1.92].

CONCLUSION

MS is a risk factor for VTE, but the absolute risk is low.

Smoking among pregnant women with disabilities

PURPOSE

The purpose of this study was to examine the prevalence of smoking before, during, and after pregnancy among a representative sample of Massachusetts women with and without disabilities.

METHODS

Data from the 2007 to 2009 Massachusetts Pregnancy Risk Assessment Monitoring System survey were used to estimate the prevalence of smoking by disability status.

MAIN FINDINGS

Disability prevalence was 4.8% (n = 204) among Massachusetts women giving birth during 2007 through 2009. The prevalence of smoking during the 3 months before pregnancy among women with disabilities was 37.3% (95% CI, 28.3-47.2%) compared with 18.3% (95% CI, 16.6-20.1%) among women without disabilities. Similarly, 25.2% (95% CI, 17.3-35.2%) of women with disabilities, compared with 9.4% of women without disabilities (95% CI, 8.1-10.8%), smoked during the last trimester of their pregnancy, and 32.1% of women with disabilities (95% CI, 23.5-42.1%) compared with 12.5% of women without disabilities (95% CI, 11.1-14.1%), smoked after pregnancy. In the multivariate logistic regression models, women with disabilities had significantly higher risks of smoking before, during and after pregnancy than women without disabilities (adjusted relative risk [aRR], 1.7 [95% CI, 1.2-2.2]; aRR, 1.9 [95% CI, 1.3-2.8]; aRR, 1.8 [95% CI, 1.3-2.5], respectively) while adjusting for race/Hispanic ethnicity, marital status, education, age, household poverty status, and infant's birth year.

IMPLICATIONS

Women with disabilities are more likely to smoke before, during, and after their pregnancy and less likely to quit smoking during pregnancy. Efforts to integrate and target pregnant women with disabilities in smoking-cessation programs are vital.

Multiple sclerosis and lung cancer: an unexpected inverse association

Multiple sclerosis is associated with a decreased risk of cancer. Smoking is a risk factor both for multiple sclerosis and lung cancer. We performed a meta-analysis on studies of cancer frequency in multiple sclerosis. Surprisingly, we found that the risk of lung cancer is reduced in multiple sclerosis [odds ratio 0.67 (95% confidence interval 0.59-0.76) P < 0.00001]. Since this does not appear to be secondary to altered smoking behaviour, we hypothesise that this may be secondary to altered immune surveillance.

Multiple sclerosis with predominant, severe cognitive impairment

OBJECTIVE

To describe the characteristics of multiple sclerosis (MS) presenting with severe cognitive impairment as its primary disabling manifestation.

DESIGN

Retrospective case series.

SETTING

Tertiary referral center. Patients Patients were identified through the Mayo Clinic data retrieval system (1996-2008) with definite MS (McDonald criteria) and severe cognitive impairment as their primary neurological symptom without accompanying significant MS-related impairment or alternative diagnosis for cognitive dysfunction. Twenty-three patients meeting inclusion criteria were compared regarding demographics, clinical course, and radiological features.

MAIN OUTCOME MEASURES

Demographic, clinical, and radiological characteristics of the disease.

RESULTS

Twelve patients were men. The median age of the first clinical symptom suggestive of central nervous system demyelination was 33 years, and severe MS-related cognitive impairment developed at a median age of 39 years. Cognitive impairment could be dichotomized as subacute fulminant (n = 9) or chronic progressive (n = 14) in presentation, which corresponded to subsequent relapsing or progressive MS courses. Study patients commonly exhibited psychiatric (65%), mild cerebellar (57%), and cortical symptoms and signs (eg, seizure, aphasia, apraxia) (39%). Fourteen of 21 (67%), where documented, smoked cigarettes. Brain magnetic resonance imaging demonstrated diffuse cerebral atrophy in 16 and gadolinium-enhancing lesions in 11. Asymptomatic spinal cord magnetic resonance imaging lesions were present in 12 of 16 patients (75%). Immunomodulatory therapies were generally ineffective in improving these patients.

CONCLUSIONS

We describe patients with MS whose clinical phenotype is characterized by severe cognitive dysfunction and prominent cortical and psychiatric signs presenting as a subacute fulminant or chronic progressive clinical course. Cigarette smokers may be overrepresented in this phenotype.

Nicotine and inflammatory neurological disorders

Cigarette smoke is a major health risk factor which significantly increases the incidence of diseases including lung cancer and respiratory infections. However, there is increasing evidence that smokers have a lower incidence of some inflammatory and neurodegenerative diseases. Nicotine is the main immunosuppressive constituent of cigarette smoke, which inhibits both the innate and adaptive immune responses. Unlike cigarette smoke, nicotine is not yet considered to be a carcinogen and may, in fact, have therapeutic potential as a neuroprotective and anti-inflammatory agent. This review provides a synopsis summarizing the effects of nicotine on the immune system and its (nicotine) influences on various neurological diseases.

Nicotinic attenuation of central nervous system inflammation and autoimmunity

The expression of nicotinic acetylcholine receptors by neurons, microglia, and astrocytes suggests possibly diverse mechanisms by which natural nicotinic cholinergic signaling and exposure to nicotine could modulate immune responses within the CNS. In this study, we show that nicotine exposure significantly delays and attenuates inflammatory and autoimmune responses to myelin Ags in the mouse experimental autoimmune encephalomyelitis model. In the periphery, nicotine exposure inhibits the proliferation of autoreactive T cells and alters the cytokine profile of helper T cells. In the CNS, nicotine exposure selectively reduces numbers of CD11c(+) dendritic and CD11b(+) infiltrating monocytes and resident microglial cells and down-regulates the expression of MHC class II, CD80, and CD86 molecules on these cells. The results underscore roles of nicotinic acetylcholine receptors and nicotinic cholinergic signaling in inflammatory and immune responses and suggest novel therapeutic options for the treatment of inflammatory and autoimmune disorders, including those that affect the CNS.

Is smoking an extra hazard in pregnant MS women? Findings from a population-based registry in Norway

Multiple sclerosis (MS) in women leads to increased risk of operative delivery and reduced birth weight, which are presumably related to the neurological dysfunction in this patient group. Lifestyle factors may also contribute, and we therefore investigated smoking habits and relevant social factors in pregnant MS women. In total, 372,128 births were registered in the compulsory Medical Birth Registry of Norway from December 1, 1998 to October 6, 2005, and of them 250 by MS mothers. The MS births were compared with all the non-MS births. Smoking during pregnancy was not increased in the MS group compared with the non-MS references. From 1998 to 2005 the MS group had a larger reduction in smoking rate during pregnancy than the reference group. The differences in pregnancy and birth outcome between smokers and non-smokers were similar in the MS and the reference group. Those in the smoking MS group had no increase in birth complications, operative interventions or negative birth outcome compared with those in the smoking reference group. Smoking during pregnancy did not explain the birth weight reduction found for newborns of MS mothers.