The epidemiology of alcohol consumption and multiple sclerosis: a review

Causal effects of dietary composition on multiple sclerosis risk and severity: a Mendelian randomization study

Objectives

Observational studies have found potential associations between dietary intake and multiple sclerosis (MS). However, these associations are inconsistent, and the causal relationship remains unclear. In this study, we aim to examine the causal relationship between genetically predicted dietary composition and the risk and severity of MS using two-sample Mendelian randomization.

Method

Genetic instruments for 30 different dietary compositions were extracted from large-scale genome-wide association studies (GWAS), mainly from the UK Biobank dataset. The GWAS data for MS risk and severity were obtained from the International Multiple Sclerosis Genetics Consortium. The primary analysis employed either the inverse variance weighted method or the Wald ratio method to evaluate the causal association. Several sensitivity analyses were also performed.

Results

Genetically predicted higher pork intake was causally associated with an increased risk of MS (odds ratio [OR] = 6.76; p = 0.005), while genetically driven higher cereal intake (OR = 0.43, p = 0.016), vitamin C supplement (OR < 0.01; p = 4.34 × 10-5), folic acid supplement (OR < 0.01; p = 4.91 × 10-71), and fish oil supplement (OR = 0.04; p = 0.017) were causally linked to a decreased risk of MS. In addition, genetically predicted higher alcoholic intake (OR = 1.17; p = 0.041) was causally associated with an increase in MS severity, while folic acid supplement (OR < 0.01; p = 0.015) was causally linked to a decrease in MS severity.

Interpretation

This study found that increased consumption of cereal, vitamin C, folic acid, and fish oil, coupled with reduced pork and alcohol intake, may potentially decrease the risk and severity of MS. These findings inform the development of dietary-based strategies for MS prevention and treatment.

Potentially modifiable associates of anxiety in people with multiple sclerosis: a systematic review

PURPOSE

A high percentage of people with multiple sclerosis (PwMS) experience anxiety, which can negatively impact quality of life. Despite this, anxiety in PwMS remains under researched. This review aims to identify associates with anxiety in PwMS that are amenable to change, with a view to informing the development of interventions in the area.

MATERIALS AND METHODS

The following databases were searched for studies investigating anxiety in PwMS from 2015 to 2021: PsycINFO, PubMed, EMBASE, Web of Science. The search consisted of keywords relating to MS and fear, anxiety or worry. Once screening was completed by two reviewers, a narrative synthesis was used to analyze the data, with the MMAT used for quality appraisal.

RESULTS

Of the 3117 unique abstracts screened, 39 studies met the criteria for inclusion. Evidence was found linking anxiety in PwMS to several modifiable factors broadly categorized as either psychological, social or lifestyle factors. Perceptions of self and one's ability to cope/adjust to MS emerged as important psychological factors. Physical activity and social support from friends were also linked with improved anxiety outcomes.

CONCLUSIONS

Anxiety in PwMS is linked to a number of modifiable factors. Findings may help inform the development of rehabilitation interventions to decrease anxiety in MS.Implications for rehabilitationThis review highlights interventions which have successfully lowered anxiety in people with MS (PwMS); however, there is a clear need for the development of further interventions which target the pathologically specific concerns surrounding anxiety in this population.We show how a number of factors amenable to change associate with anxiety, suggesting that these factors may be appropriate targets for anxiety interventions in PwMS.Enhancing physical activity and self-efficacy are important means in which healthcare professionals can reduce anxiety in MS.Identifying ways of encouraging positive coping and increasing social support are further targets for improving comorbid anxiety in PwMS.Focusing on the modifiable factors highlighted here offers considerable potential for enhancing psychological wellbeing in this group.

Effect of Seasonal Variation on Relapse Rate in Patients With Relapsing-Remitting Multiple Sclerosis in Saudi Arabia

Multiple sclerosis (MS) is becoming a global subject of study in which some demographic variations are thought to be correlated with its activity. Relapsing-remitting multiple sclerosis (RRMS) is the most common demyelinating disorder, characterized by periods of exacerbating attacks, followed by partial or complete remission. Several factors might play a role in disease progression and relapse frequency, such as vitamin D, ultraviolet B radiation, estrogen levels, smoking, obesity, and unhealthy lifestyles. In this study, we identified the relationship between seasonal variation and relapse rate and correlated the latter with sex, age, and vitamin D levels in patients with RRMS in Jeddah, Saudi Arabia. We retrospectively collected data from 182 RRMS patients between 2016 and 2021. A total of 219 relapses were documented in 106 patients (58.2 %). The relapse per patient ratio showed a sinusoidal pattern, peaking in January at a rate of 0.49 and troughed in June at a rate of 0.18. There was no difference in relapse rates between men and women (p =0.280). There was a significant negative correlation between vitamin D levels and relapse rate (r = −0.312, p =0.024). Therefore, the relapse rate was higher during the winter and was correlated with low vitamin D levels. However, relapses are likely multifactorial, and more population-based studies are needed to understand the role of environmental variables in MS exacerbation. A better understanding of this relationship will allow for improved treatment and possibly better prevention of relapse.

Cladribine as a Potential Object of Nucleoside Transporter-Based Drug Interactions

Cladribine is a nucleoside analog that is phosphorylated in its target cells (B and T-lymphocytes) to its active triphosphate form (2-chlorodeoxyadenosine triphosphate). Cladribine tablets 10 mg (Mavenclad^®), administered for up to 10 days per year in 2 consecutive years (3.5-mg/kg cumulative dose over 2 years), are used to treat patients with relapsing multiple sclerosis. Cladribine has been shown to be a substrate of various nucleoside transporters (NTs). Intestinal absorption and distribution of cladribine throughout the body appear to be essentially mediated by equilibrative NTs (ENTs) and concentrative NTs (CNTs), specifically by ENT1, ENT2, ENT4, CNT2 (low affinity), and CNT3. Other efficient transporters of cladribine are the ABC efflux transporters, specifically breast cancer resistance protein, which likely modulates the oral absorption and renal excretion of cladribine. A key transporter for the intracellular uptake of cladribine into B and T-lymphocytes is ENT1 with ancillary contributions of ENT2 and CNT2. Transporter-based drug interactions affecting absorption and target cellular uptake of a prodrug such as cladribine are likely to reduce systemic bioavailability and target cell exposure, thereby possibly hampering clinical efficacy. In order to manage optimized therapy, i.e., to ensure uncompromised target cell uptake to preserve the full therapeutic potential of cladribine, it is important that clinicians are aware of the existence of NT-inhibiting medicinal products, various lifestyle drugs, and food components. This article reviews the existing knowledge on inhibitors of NT, which may alter cladribine absorption, distribution, and uptake into target cells, thereby summarizing the existing knowledge on optimized methods of administration and concomitant drugs that should be avoided during cladribine treatment.

Alcohol Consumption and Risk of Common Autoimmune Inflammatory Diseases-Evidence From a Large-Scale Genetic Analysis Totaling 1 Million Individuals

Purpose: Observational studies have suggested a protective effect of alcohol intake with autoimmune disorders, which was not supported by Mendelian randomization (MR) analyses that used only a few (<20) instrumental variables.

Methods: We systemically interrogated a putative causal relationship between alcohol consumption and four common autoimmune disorders, using summary-level data from the largest genome-wide association study (GWAS) conducted on inflammatory bowel disease (IBD), rheumatoid arthritis (RA), multiple sclerosis (MS), and systemic lupus erythematosus (SLE). We quantified the genetic correlation to examine a shared genetic similarity. We constructed a strong instrument using 99 genetic variants associated with drinks per week and applied several two-sample MR methods. We additionally incorporated excessive drinking as reflected by alcohol use disorder identification test score.

Results: We observed a negatively shared genetic basis between alcohol intake and autoimmune disorders, although none was significant (r_g = −0.07 to −0.02). For most disorders, genetically predicted alcohol consumption was associated with a slightly (10–25%) decreased risk of onset, yet these associations were not significant. Meta-analyzing across RA, MS, and IBD, the three Th1-related disorders yielded to a marginally significantly reduced effect [OR = 0.70 (0.51–0.95), P = 0.02]. Excessive drinking did not appear to reduce the risk of autoimmune disorders.

Conclusions: With its greatly augmented sample size and substantially improved statistical power, our MR study does not convincingly support a beneficial role of alcohol consumption in each individual autoimmune disorder. Future studies may be designed to replicate our findings and to understand a causal effect on disease prognosis.

Perspectives on urological care in multiple sclerosis patients

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system. Lower urinary tract dysfunction due to MS includes a dysfunction of the storage phase or dysfunction of the voiding phase or a detrusor-sphincter dyssynergia. Baseline evaluation includes a voiding chart, an ultrasound scan of the urinary tract, urine culture, and an urodynamic study. For storage symptoms, antimuscarinics are the first-line treatment, and clean intermittent catheterization (CIC) is indicated if there is concomitant incomplete bladder emptying. Intradetrusor injections with botulinum toxin A (BTX-A), are recommended for refractory cases. Urinary diversion is rarely indicated. For patients with voiding symptoms, CIC and alpha-blockers are usually offered. Sexual dysfunction in patients with MS is multifactorial. Phosphodiesterase type 5 inhibitors are first-line therapies for MS-associated erectile dysfunction in both male and female patients. This review summarizes the epidemiology, pathogenesis, risk factors, genetic, clinical manifestations, diagnostic tests, and management of MS. Lastly, the urologic outcomes and therapies are reviewed.

Lung cancer risk in patients with multiple sclerosis: a Mendelian randomization analysis

BACKGROUND

The relationship of multiple sclerosis (MS) with lung cancer is under debate. Conventional observational studies have reported conflicting findings, but such studies are susceptible to confounding and reverse causation. With a Mendelian Randomization approach, we were able to evaluate the causality between MS and lung cancer.

METHODS

According to published genome-wide association studies (GWASs), we obtained 35 MS-related single-nucleotide polymorphisms, which were used as instrumental variables in our study. Summary data of individual-level genetic information were obtained from the International Lung Cancer Consortium (ILCCO), with a total of 15,861 controls and 11,348 cases; the latter is composed of patients with lung adenocarcinoma and squamous cell lung cancer. The inverse variance-weighted method was applied to estimate the causation between MS and lung cancer. To further evaluate the pleiotropy, the MR-Egger and Weighted median methods were implemented.

RESULTS

The results of MR analysis suggested a causal effect of MS on lung cancer incidence, with evidence of an increased risk for overall lung cancer [odds ratio (OR): 1.0648; 95% confidence interval (CI): 1.0163-1.1156; p = 0.0082]. However, subgroup analyses showed no significant causal relationships between MS and lung adenocarcinoma (OR = 1.0716; 95% CI 0.9840-1.1671, p = 0.1119) and squamous cell lung cancer (OR = 1.0284; 95% CI 0.9575-1.1045, p = 0.4424). In addition, no pleiotropy was found in our study.

CONCLUSION

Our study indicated that MS is a causal risk factor in the development of lung cancer. Further work is needed to elucidate the potential mechanisms.

Symptom Management and Lifestyle Modifications in Multiple Sclerosis

PURPOSE OF REVIEW

This article reviews the rationale and approach to symptom management and lifestyle modifications in multiple sclerosis (MS).

RECENT FINDINGS

MS symptoms are important to treat because they affect quality of life and daily activity. Appreciation of cluster symptoms (where one symptom contributes to another), changes over time, and multimodality therapeutic approaches are guiding optimized symptom management. Equally important are lifestyle modifications that enhance central nervous system reserve and function. These modifications are the foundation for a health maintenance, wellness, and vascular risk factor control program.

SUMMARY

Symptom management and lifestyle modifications are important therapeutic targets to improve the lives of patients with MS.