The Effect of Vitamin D Supplements on Clinical and Para-Clinical Outcomes in Patients With Multiple Sclerosis: Protocol for a Systematic Review

Impact of menopause on relapse rate and disability level in patients with multiple sclerosis (MS): a systematic review and meta-analysis

BACKGROUND

Menopause is a physiologic phase in women's lives. Findings regarding multiple sclerosis (MS) course through menopause are diverse. So, we designed this systematic review and meta-analysis to estimate the impact of menopause on relapse rate, and disability status in women with MS.

METHODS

PubMed, Scopus, EMBASE, Web of Science, and google scholar were systematically searched by two independent researchers on January 1st, 2023. They also evaluated conference abstracts, and references of the included studies. In addition, data regarding the total number of participants, name of the first author of the publication, publication year, country of origin, disease duration, disease type, annual relapse rate, and Expanded Disability Status Scale (EDSS) before and after menopause were recorded.

RESULTS

A literature search revealed 1024 records. Twenty-one full texts were evaluated, and finally, four studies were included for meta-analysis. Mean ARR before menopause ranged between 0.21 and 0.37, and after menopause ranged between 0.13 and 0.08. The SMD of mean ARR ranged between - 1.04, and - 0.29, while the pooled SMD was estimated as -0.52(95% CI: -0.88, -0.15) (I2 = 73.6%, P = 0.02). The mean EDSS before menopause ranged between 1.5 and 2, and after menopause ranged between 2 and 3.1. The SMD of EDSS ranged between 0.46, and 0.71. The pooled SMD of EDSS change (after menopause-before menopause) estimated as 0.56(95% CI: 0.38, 0.73)(I2 = 0, P = 0.4).

CONCLUSION

The result of this systematic review and meta-analysis show that menopause can be associated with relapse rate reduction, unlike increase in disease-related disability in women with MS.

The prevalence of cancer in patients with multiple sclerosis (MS) who received rituximab: a systematic review and meta-analysis

OBJECTIVE

To estimate the pooled prevalence of cancer in patients with multiple sclerosis (MS) cases who were under treatment with rituximab.

METHODS

We searched PubMed, Scopus, EMBASE, Web of Science, and google scholar along with gray literature up to April 2021. The search strategy included the MeSH and text words as (("CD20 Antibody" AND Rituximab) OR "Rituximab CD20 Antibody" OR Mabthera OR "IDEC-C2B8 Antibody" OR "IDEC C2B8 Antibody" OR IDEC-C2B8 OR "IDEC C2B8" OR GP2013 OR Rituxan OR rituximab) AND ((Sclerosis AND multiple) OR (sclerosis AND disseminated) OR "disseminated sclerosis" OR "multiple sclerosis" OR "acute fulminating").

RESULTS

The literature search revealed 3577 articles, after deleting duplicates 2066 remained. For the meta-analysis, 22 studies were included. Totally, 15599 patients were enrolled while 133 cancers were detected. The pooled prevalence of cancer in MS patients under treatment with rituximab is 1in 100,000 (I2 = 99.9%, p < 0.001).

CONCLUSION

The results of this systematic review and meta-analysis show that the pooled prevalence of cancer in MS patients who received rituximab is 1 in 100,000 cases.

Pregnancy History, Oral Contraceptive Pills Consumption (OCPs), and Risk of Multiple Sclerosis: A Systematic Review and Meta-Analysis

Background

To estimate the pooled odds of oral contraceptive pills consumption (OCPs) use as well as pregnancy history and multiple sclerosis (MS) risk.

Methods

We systematically searched PubMed, Embase, Scopus, Web of Science, Google scholar, and gray literature including references of the references as well as conference papers. The search strategy in PubMed was ((Oral contraceptive pills) OR OCP) AND (Multiple Sclerosis OR Sclerosis, Multiple) OR Sclerosis, Disseminated) OR Disseminated Sclerosis) OR MS (Multiple Sclerosis)) OR Multiple Sclerosis, Acute Fulminating) AND (gravidity) OR (pregnancy).

Results

Four studies were included. The pooled odds of developing MS in women with pregnancy history compared with nulligravid women was 0.64 (95%CI = 0.53 - 0.78) (I ² = 0, P = 0.5), which means that pregnancy reduces the risk of MS by 36%. The pooled odds of OCP consumption and risk of MS were 1.09 (95% CI = 0.67 - 1.76). By comparing the pooled odds of OCP consumption and risk of MS according to the country of the origin, we found that the pooled odds in Iranian studies was 1.03 (95% CI = 0.31 - 3.45) and the pooled OR in studies that were conducted in the United States was 1.13 (95% CI = 0.65 - 1.98), which showed that the country of the origin was not the cause of heterogeneity.

Conclusions

The results of this systematic review show that pregnancy history is a protective factor for MS development, whereas OCP use has no significant effect.

The prevalence of osteoporosis/osteopenia in patients with multiple sclerosis (MS): a systematic review and meta-analysis

BACKGROUND

The prevalence of osteoporosis is reported differently. We designed this systematic review and meta-analysis to estimate pooled prevalence of osteoporosis and osteopenia in patients with MS.

METHODS

Independently, two researchers searched PubMed, Scopus, EMBASE, Web of Science, and google scholar along with gray literature (conference abstracts and references of the references) up to March 2021. We collected data regarding first author, country of origin, number of enrolled patients, number cases with osteoporosis/ osteopenia, mean age, F/M ratio, mean EDSS, and mean duration of the disease.

RESULTS

Literature search revealed 847 articles and 658 remained after deleting duplicates. Finally, 29 original articles and 6 conference papers remained for meta-analysis. A total of 13,906 patients were evaluated. The pooled prevalence of osteoporosis was 17% (95% CI: 14-20%) (I² = 90.4%, p < 0.001). The pooled prevalence of osteopenia was 43% (95% CI: 35-51%) (I² = 97.9%, p < 0.001).

CONCLUSION

Osteoporosis/osteopenia should be considered in patients with MS.

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

Background

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

Methods

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

Results

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

Conclusions

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

Effect of Vitamin D Supplements on Relapse Rate and Expanded Disability Status Scale (EDSS) in Multiple Sclerosis (MS): A Systematic Review and Meta-Analysis

Background

Multiple sclerosis (MS) is an inflammatory disease while there are controversies regarding the role of vitamin D supplements in controlling relapse and disability improvement during treatment.

Objective

The goal of this systematic review and meta-analysis was to evaluate the effect of vitamin D supplements on MS-related relapse and the Expanded Disability Status Scale (EDSS).

Methods

We searched databases to include randomized clinical trials (RCTs) which were published up to October 2018. We included RCTs, being single-blinded or double-blinded or open-label trials in which one of the main outcomes was EDSS and/or relapse after vitamin D supplementation. All statistical analyses were performed using RevMan 5.3. Odds ratios (OR) and 95% confidence intervals (CI) were calculated for relapse between treatment arms. The mean difference was calculated for EDSS comparisons.

Results

Nine articles were included for analysis. Of these nine studies, five compared vitamin D supplement groups with placebo (group 1 studies), and four compared high- and low-dose vitamin D groups. A total of 561 patients were analyzed. Being treated with vitamin D instead of placebo showed no effect on relapse rate (OR = 0.66, 95% CI = 0.28-1.54) as well as EDSS (mean difference = 0.06, 95%CI [-0.31, 0.42]). The results of studies comparing high- vs. low-dose vitamin D interventions showed no significant effect on relapse rate (OR = 1.08, 95%CI [0.29-4.08] as well as final EDSS (mean difference = 0.17, 95% CI = -0.73, 1.07).

Conclusions

Our findings show that vitamin D supplements (high or low dose) have no significant effect on relapse rate and disability during treatment in MS patients.

Risk of cancer in multiple sclerosis (MS): A systematic review and meta-analysis

OBJECTIVE

To assess the pooled risk of cancer in patients with multiple sclerosis.

METHODS

We searched PubMed, Scopus, EMBASE, Web of Science, Ovid, google scholar and gray literature (references of studies, conference abstracts) which were published up to September 2019. The search strategy included the MeSH and text words as ((cancer) OR tumor) OR neoplasm) OR "malignant neoplasm) OR "benign neoplasm) AND (Multiple Sclerosis OR Sclerosis, Multiple) OR Sclerosis, Disseminated) OR Disseminated Sclerosis) OR MS (Multiple Sclerosis)) OR Multiple Sclerosis, Acute Fulminating).

RESULTS

The first literature search revealed 18,996 articles. After deletion of duplicate articles, finally, 264 articles remained. Excluding non-relevant articles, resulted in including 5 articles which met inclusion criteria. The RR estimated between 0.7 and 1.67 in included articles. The pooled RR estimated as 0.83 (95% CI:0.73-0.96) (I² = 90%, P < 0.001). Two studies provided prevalence of different cancers. The pooled prevalence of breast cancer in two studies was 2% (95%CI:2%-2%) (I² = 0%). The pooled prevalence of digestive system cancer in two studies was 2% (95%CI:1%-2%) (I² = 0%). The pooled prevalence of skin cancer in two studies was 1% (95%CI:0%-1%) (I² = 0).

CONCLUSION

The result of this systematic review showed that the risk of cancer in patients with MS is less than the general population.

Effects of Vitamin D Supplements on IL-10 and INFγ Levels in Patients with Multiple Sclerosis: a Systematic Review and Meta-Analysis

Background:Vitamin D is one of the considerable environmental factors exhibiting immunomodulatory and anti-inflammatory effects. Objective: To conduct a systematic review and meta-analysis to estimate the effect of vitamin D supplements on IL-10 and INFγ levels in patients with multiple sclerosis. Methods: We searched PubMed, Scopus, EMBASE, CINAHL, Web of Science, Ovid, The Cochrane Library and gray literature, including references of selected studies, conference abstracts which were published up to May 2019. We included single- or double-blinded RCTs or open-label trials in which one of the main outcomes was INFγ and/ or IL-10 levels after vitamin D supplementation. Only articles that had been published in English were included. Results: The literature search yielded 369 articles, that were monitored by us. After eliminating duplicates, 128 studies remained; from these, we excluded observational studies, reviews, case reports and non-randomized trials, and 33 studies remained. Finally, only three articles were included. The mean difference for INFγ was 268.4 and 95 % CI 200.6-336.1. There was no significant heterogeneity (I ² = 0 %, Chi ² = 0.1, p = 0.7). The mean difference for IL-10 was 398.3 and 95% CI -528.05-1324.8). There was significant heterogeneity (I2 = 94 %, Chi2 = 31.1 p < 0.001). Conclusion: The results of this systematic review were not satisfactory. More clinical trials are further needed to evaluate the effects of vitamin D supplements on IL-10 and INFγ levels in patients with multiple sclerosis.

Age at menarche and risk of multiple sclerosis (MS): a systematic review and meta-analysis

BACKGROUND

Some studies have looked at the age at menarche and risk of Multiple Sclerosis (MS).We aimed to conduct a systematic review and meta-analysis to estimate a pooled odds ratio of developing MS by increasing age at menarche.

METHODS

We searched PubMed, Scopus, EMBASE, CINAHL, Web of Science, Ovid, google scholar and gray literature (references of references, congress abstracts) up to 10th April 2019.

RESULTS

The literature search found 312 articles. After eliminating duplicates, reviews, case reports and trials, 18 articles remained. Three articles were ultimately included in the final analysis. Two studies were from Iran, and one from Canada. The pooled odds ratio (OR) for increasing 1 year of age at menarche was 0.88 (95% CI:0.82-0.94), with no significant heterogeneity (I2 = 49%, p = 0.1). Mean age at menarche was significantly different between case and control groups (mean difference = - 0.22, 95% CI = -0.42,-0.02).

CONCLUSION

The result of this systematic review showed that the risk of MS decreases by increasing age at menarche.