The global prevalence of familial multiple sclerosis: an updated systematic review and meta-analysis

Familial vs sporadic multiple sclerosis in the Israeli population: Differences in ethnicity distribution and disease progression, with anticipation in successive generations

BACKGROUND

Multiple Sclerosis (MS) may cluster in families, an entity known as familial MS (FMS), possibly due to aggregation of genetic and environmental factors. Though previous studies have characterized FMS in different populations, no study to the best of our knowledge has yet characterized FMS in the unique Israeli population, which is comprised of relatively endogamous ethnicities. Our goal in this study was to compare demographic and clinical characteristics between FMS and sporadic MS (SMS), and to search for intra-familial patterns.

METHODS

In a retrospective study of 101 FMS patients and 508 SMS patients, ethnicity and sex distribution was assessed. Clinical aspects were compared between 172 paired FMS and SMS patients, matched for sex, age and ethnicity, and between generations of the FMS cohort.

RESULTS

Females comprised 75.3 % of FMS and 67.5 % of SMS patients (p = 0.1). Ethnic distribution was significantly different between FMS and SMS (p = 0.014), with the former comprising a higher proportion of Christian-Arabs (15.4% vs. 5.1 %, p = 0.004) and lower proportion of Jews (60% vs. 74.2 %, p = 0.016). Age at disease onset or diagnosis, frequency of positive Oligoclonal bands and comorbidity of other autoimmune/inflammatory disease or chronic diseases was comparable between FMS and SMS, yet motor symptoms at onset were more prevalent in FMS (34% vs. 20 %, p = 0.02). Annualized relapse rates throughout 10 years from onset were comparable. Among FMS, mean Expanded-Disability-Status-Scale (EDSS) and slope of deterioration in EDSS over 20 years from diagnosis were higher (p = 0.0004 and p = 0.023, respectively), time to EDSS ≥ 3 was shorter (7.1 vs. 12.1 years, HR 1.6, p = 0.036) and MS-Severity-Score (MSSS) was higher (3.84 vs. 2.95, p = 0.04), compared to SMS. Following adjustment for smoking, which tended to be higher among FMS patients (P = 0.06), mean EDSS and slope of deterioration in EDSS over 20 years remained significantly higher (p = 0.0006 and p = 0.025, respectively) in FMS, time to EDSS ≥ 3 tended to be higher (HR 1.5, p = 0.06), while MSSS was comparable. An inter-generational analysis of the total FMS cohort, as well as an intra-familial analysis, both adjusted for year of diagnosis, revealed significantly earlier age of onset (p < 0.0001 and p < 0.0001) and diagnosis (p = 0.001 and p < 0.0001) in the younger compared to the older generations, respectively.

CONCLUSION

In this Israeli cohort, the proportions of specific ethnicities differ between FMS and SMS, indicating that FMS has a population-specific prevalence pattern, and that further investigation for susceptibility genes is warranted. Disease progression is faster in FMS patients and anticipation is observed in families with multiple cases of MS. Closer surveillance and application of a pro-active induction or early highly-effective therapeutic strategy for FMS patients should be considered, to reduce high disease activity and fast disability progression.

Clinical characteristics and dynamics of disability progression in a cohort of patients with multiple sclerosis in Latvians

There is wide variation in the time from the onset to secondary progressive multiple sclerosis (MS) and some controversy regarding the clinical characteristics of the courses (phenotypes) of MS. The present study aimed to characterize demographic and clinical factors that potentially influence long-term disability progression in the cohort of Latvian MS patients. A descriptive longitudinal incidence study was conducted using a cohort of 288 MS patients beginning in 2011 (disease duration from 1 to 51 years). Socio-demographic and clinical information from the first visit to 15/20 years was analysed in groups stratified by gender and visits at five-time points (the first visit; after a year or 2; after 5 ± 1 year; after 10 ± 2 years; after 15-20 years). Our study was dominated by patients from urban areas and non-smokers. The female/male ratio was 2.4:1; the distribution of clinical courses at the first visit was consistent with most European studies. The most common symptom at presentation in our study was optic manifestations, followed by sensory disturbances and motor deficits. In the Latvian study, gender was not a significant influencing factor on the rate of disease progression; however, patient age was statistically significantly associated with EDSS (Expanded Disability Status Scale) value at the first visit. Early clinical features of MS are important in predicting the disability accumulation of patients. Despite the small differences regarding the first MS symptoms, the disability outcomes in the cohort of Latvian patients are similar to other regions of the world.

Earlier age of symptom onset in younger generation of familial cases of multiple sclerosis

AIM

The aim of this study was to assess the prevalence of familial MS (fMS) in Belgrade MS population, discern the differences between the persons with fMS and sporadic MS, and to detect the presence of anticipation phenomenon in fMS patients.

METHODS

The data on the demographic and clinical characteristics of MS patients was obtained from the Belgrade MS population Registry. In cases of vertical transmission of MS, the family members were divided into the younger and older generation, in order to assess the potential presence of anticipation phenomenon. To adjust for follow-up time bias, a secondary analysis including only patients who had the onset of symptoms before 39 years (75.percentile), and those who were 39 + years, was performed.

RESULTS

The prevalence of fMS in Belgrade MS population is 6.4%. FMS cases had earlier age at MS symptom onset (30.4 vs. 32.3 years) compared to sporadic MS cohort. When comparing fMS cases across generations, the younger generation had significantly lower age at onset compared with the older one (25.8 vs. 35.7 years, p < 0.001). After adjustment for the different length of the follow-up, the difference in age at symptom onset between the groups was reduced, but it still existed and was statistically significant (30.0 years in younger vs. 36.4 years in older generation, p = 0.040).

CONCLUSION

In our study, the analysis of fMS cases across generations, showed an earlier age of symptom onset in the younger generation, even after adjustment. These results indicate the possibility of existence of anticipation phenomenon.

Exclusive breastfeeding may be a protective factor in individuals with familial multiple sclerosis. A population registry-based case-control study

BACKGROUND

Multiple sclerosis (MS) is an immune-mediated disease that affects the central nervous system, which most likely results from the interplay between environmental and genetic factors. The aim of our study was to assess the effect of breastfeeding on the risk of developing familial multiple sclerosis (fMS) in persons with positive MS history, being the first such investigation performed in fMS cohort.

METHODS

A case-control study based on the Belgrade population MS Registry was conducted. Cases for the sporadic MS (sMS) control group were randomly selected from the Registry, and matched with individuals with fMS at a ratio of 1:1. Spouses of the persons with fMS were included as a healthy control (HC) group. A specific questionnaire that was previously validated was used to obtain the data. To evaluate risk factors associated with breastfeeding for fMS occurrence compared with sMS and HC, multinomial regression analysis was performed to compute the relative risk ratios (RRR) along with 95% confidence intervals (95% CI). The analysis was afterwards repeated, stratified by sex. Both models were adjusted for potential confounding factors.

RESULTS

A total of 393 participants were included in our case-control study, 131 per group. There were more individuals who were exclusively breastfed longer than six months in the sMS group compared to fMS group (RRR 2.01, 95% CI 1.22-3.32). After stratification by sex, exclusive breastfeeding was shown to be a protective factor for fMS only in male population, for individuals breastfed ≥4 months. The results of both the main and stratified analysis remained robust after adjustment.

CONCLUSION

Our study findings indicate that breastfeeding reduces the risk of MS in infants with family history of the disease, although this protective effect may be limited to the male population. Further investigation into the differences in risk factors between fMS and sMS is warranted to gain a more comprehensive understanding of the disease.

Genetic Variant HLA-DRB1*0403 and Therapeutic Response to Disease-Modifying Therapies in Multiple Sclerosis: A Case-Control Study

Multiple sclerosis (MS) is a chronic and demyelinating disease with an autoimmune origin, which leads to neurodegeneration and progressive disability. Approximately 30 to 50% of patients do not respond optimally to disease-modifying therapies (DMTs), and therapeutic response may be influenced by genetic factors such as genetic variants. Therefore, our study aimed to investigate the association of the HLA-DRB1*0403 genetic variant and therapeutic response to DMTs in MS. We included 105 patients with MS diagnosis. No evidence of disease activity based on the absence of clinical relapse, disability progression or radiological activity (NEDA-3) was used to classify the therapeutic response. Patients were classified as follows: (a) controls: patients who achieved NEDA-3; (b) cases: patients who did not achieve NEDA-3. DNA was extracted from peripheral blood leukocytes. HLA-DRB1*0403 genetic variant was analyzed by quantitative polymerase chain reaction (qPCR) using TaqMan probes. NEDA-3 was achieved in 86.7% of MS patients treated with DMTs. Genotype frequencies were GG 50.5%, GA 34.3%, and AA 15.2%. No differences were observed in the genetic variant AA between patients who achieved NEDA-3 versus patients who did not achieve NEDA-3 (48.7% vs. 43.1%, p = 0.6). We concluded that in Mexican patients with MS, HLA-DRB1*0403 was not associated with the therapeutic response to DMTs.

Economic and Social Standing of Individuals in Iran Diagnosed with Multiple Sclerosis

BACKGROUND

Multiple sclerosis (MS) may be affected by socioeconomic status (SES). This study aims to explore the determinants of SES among Iranian patients with MS and examine how these factors relate to disability and disease progression.

METHODS

All patients with MS listed in the nationwide MS registry of Iran (NMSRI) until January 8, 2022, were included in this population-based study.

RESULTS

Among the 5153 patients, most were female (74.5%), married (70.8%), and did not hold an academic degree (53.8%). Unemployment (OR: 3.75) and being unmarried (OR: 2.60) were significantly associated with Expanded Disability Status Scale (EDSS)≥6, and the time to progression was shorter in the unemployed group (P value: 0.03). There was also a significant negative correlation between the time to progression and the age at disease onset.

CONCLUSION

The study suggests that providing financial and social support to MS patients and their families through investment could reduce both individual and societal burdens.

Late-onset multiple sclerosis in Iran: A report on demographic and disease characteristics

BACKGROUND

Today, it is estimated that around 5% of multiple sclerosis (MS) patients are in the late-onset category (age at disease onset ≥ 50). Diagnosis and treatment in this group could be challenging. Here, we report the latest update on the characteristics of Iranian patients with late-onset MS (LOMS).

METHODS

This cross-sectional study used the information provided by the nationwide MS registry of Iran (NMSRI). The registrars from 14 provinces entered data of patients with a confirmed diagnosis of MS by neurologists. Patients with disease onset at or later than 50 years of age were considered LOMS.

RESULTS

Of 20,036 records, the late-onset category included 321 patients (1.6%). The age-standardized LOMS prevalence was around 75 per 100,000 people. 215 patients (67%) were female. Median Expanded Disability Status Scale (EDSS) was 3 (interquartile range: 1.5-5). The majority of the cases (56%) suffered from relapsing-remitting (RR) course while 20% were diagnosed with primary progressive (PP) MS. Significantly higher proportion of male sex, PPMS, and higher EDSS were seen in the late-onset group compared with early-onset and adult-onset cases (p-value < 0.05). Seventy-five (23%) patients did not receive any disease-modifying treatment.

DISCUSSION

The more prominent degenerative pathology of LOMS may be the underlying mechanism of the observed differences in comparison to non-LOMS.

CONCLUSION

There are substantial differences and knowledge gaps regarding LOMS which could be the subject of further research.

The global prevalence of sexual dysfunction in women with multiple sclerosis: a systematic review and meta-analysis

BACKGROUND

Sexual function is often impaired following neurological disorders such as multiple sclerosis (MS). Young women with MS encourage disruptions in sexual function, sexual behaviors, and family formation as common global problems. Thus, the aim of the present systematic review and meta-analysis study was to investigate the global prevalence of female sexual dysfunction (FSD) worldwide.

METHODS

Various databases (PubMed, Scopus, Web of Science, Embase, and ScienceDirect) along with Google Scholar search engine were hired for systematic searching in the field of the prevalence of FSD (by July 2022). The heterogeneity of the studies was assessed using I² index, and random effects model was used to perform the analysis (CMA software, v.2).

RESULTS

Following assessment of 14 included studies with the sample size of 2115 women, a total prevalence of sexual dysfunction (SD) in women with MS was reported 62.5% (95% CI 53.9-70.5). Meta-regression assessment also showed that FSD accelerates following increasing the sample size and the year of the studies.

CONCLUSION

The total prevalence of SD in women with MS was found considerably high (62.5%) in the world, which needs more serious attention by health policymakers. Correct implementation of health policies can potentially increase the society's awareness and successful treatment of SD in MS patients.

Epidemiology of familial multiple sclerosis and its comparison to sporadic form in Markazi Province, Iran

BACKGROUND

Limited data have been published about the epidemiology of familial multiple sclerosis (FMS) and its comparison to the sporadic form. Additionally, the epidemiology of FMS varies significantly in numerous provinces of Iran.

OBJECTIVES

The current study aimed to establish the epidemiology and clinical presentations of FMS and compare this form of the disease to sporadic multiple sclerosis (SMS) in Markazi province, Iran.

METHODS

In this cross-sectional registry-based study, the data were collected by the Multiple Sclerosis (MS) Society of Markazi province within 2012-2021. The demographic and clinical characteristics, diagnosis, and treatment of the MS patients living in the province were registered in this system.

RESULTS

A total of 924 MS cases who completed the data about the familial history of MS participated in this study. Based on the results, the female/male ratios were equal to 3.11 and 3.96 in FMS and SMS groups, respectively. Furthermore, 29.4% of the individuals had a history of the disease in their first- to third-degree relatives. The prevalence of primary-progressive multiple sclerosis was higher among the FMS patients (8.5%) than in the SMS patients (4.6%). Along with motor, sphincter, cognitive, and brain stem signs as the onset symptoms, the FMS group experienced a higher rate of polysymptomatic onset (P = 0.000). Moreover, significantly more autoimmune diseases and consanguineous marriages (P = 0.000) were observed in the FMS group than in the SMS group. The individuals with FMS reported a higher mean number of recurrences and higher Expanded Disability Status Scale (EDSS) scores (P = 0.000).

CONCLUSION

The results showed a significant prevalence of FMS in Markazi province. The FMS and SMS patients were significantly different regarding first presentations, onset symptoms, MS clinical characteristics, and EDSS scores. Finally, consanguineous marriage was significantly more common in the FMS group than in the SMS group.

Optical coherence tomography assessment of axonal and neuronal damage of the retina in patients with familial and sporadic multiple sclerosis

Objective

To assess axonal and neuronal damage of the retina in patients with familial (fMS) and sporadic multiple sclerosis (sMS).

Methods

87 relapsing-remitting MS patients (45 patients with sMS, 42 patients with fMS) and 30 healthy controls were included in the study. Optical coherence tomography (OCT) was performed with the spectral domain optical coherence tomography (SD-OCT, Heidelberg Engineering, Germany). The peripapillary retinal nerve fiber layer (pRNFL) thickness, ganglion cell-inner plexiform layer (GCIPL) thickness, total macular volume (TMV) and the inner nuclear layer (INL) thickness were measured.

Results

A significant reduction of the pRNFL thickness was detected in sMS and fMS compared to the control group (86.29 (+/- 16.13) μm in sMS, 84.78 (+/- 12.92) μm in fMS, 98.93 (+/- 6.71) μm in control group; p < 0.001). There was no significant difference in the pRNFL thickness between sMS and fMS (p = 0.5239). The GCIPL thickness was significantly decreased in sMS and fMS compared to the control group [66.0581 (+/- 11.2674) μm in sMS, 63.8386 (+/-10.004) μm in fMS, 76.5074 (+/- 5.0004) μm in control group; p < 0.001]. A significant reduction of the TMV was shown in sMS and fMS compared to the control group [8.4541(+/- 0.4727) mm3 in sMS, 8.3612 (+/- 0.4448) mm3 in fMS, 8.8387 (+/- 0.314) mm3 in control group; p < 0.0011]. No difference in the GCIPL thickness and TMV between sMS and fMS was found (p = 0.3689 and p = 0.3758, respectively). The INL thickness in sMS and fMS did not differ compared to the control group [34.2323 (+/- 2.7006) μm in sMS, 34.5159 (+/- 2.9780) μm in fMS, 33.6148 (+/- 2.0811) μm in control group; p = 0.5971 and p = 0.1870, respectively] and between the two forms (p = 0.4894).

Conclusion

We confirmed the presence of axonal and neuronal damage of the retina in sMS and fMS. Both forms of MS did not differ significantly from each other with respect to RFNL, GCIPL, MV and INL. ON induced significant reduction of the pRNFL, GCIPL and MV in both groups of pwMS.

Cytokine Secretion Dynamics of Isolated PBMC after Cladribine Exposure in RRMS Patients

Cladribine (CLD) treats multiple sclerosis (MS) by selectively and transiently depleting B and T cells with a secondary long-term reconstruction of the immune system. This study provides evidence of CLD’s immunomodulatory role in peripheral blood mononuclear cells (PBMCs) harvested from 40 patients with untreated relapsing-remitting MS (RRMS) exposed to CLD. We quantified cytokine secretion from PBMCs isolated by density gradient centrifugation with Ficoll−Paque using xMAP technology on a FlexMap 3D analyzer with a highly sensitive multiplex immunoassay kit. The PBMC secretory profile was evaluated with and without CLD exposure. PBMCs isolated from patients with RRMS for ≤12 months had significantly higher IL-4 but significantly lower IFN-γ and TNF-α secretion after CLD exposure. PBMCs isolated from patients with RRMS for >12 months had altered inflammatory ratios toward an anti-inflammatory profile and increased IL-4 but decreased TNF-α secretion after CLD exposure. CLD induced nonsignificant changes in IL-17 secretion in both RRMS groups. Our findings reaffirm CLD’s immunomodulatory effect that induces an anti-inflammatory phenotype.

Epidemiology of familial multiple sclerosis in Iran: a national registry-based study

Background

Admittedly, little is known about the epidemiological signatures of familial multiple sclerosis (FMS) in different geographical regions of Iran.

Objective

To determine the epidemiology and the risk of FMS incidence in several provinces of Iran with a different ethnic population including, Fars, Tehran, Isfahan (Persians), and Mazandaran (Mazanis), Kermanshah (Kurds), and Chaharmahal and Bakhtiari (Lors).

Methods

This cross-sectional registry-based study was performed on nationwide MS registry of Iran (NMSRI) data collected from 2018 to 2021. This system, registers baseline characteristics, clinical presentations and symptoms, diagnostic and treatments at regional and national levels.

Results

A total of 9200 patients including, 7003 (76.1%) female and 2197 (23.9%) male, were participated. About 19% of patients reported a family history of MS; the order from highest to lowest FMS prevalence was as follows: Fars (26.5%), Chaharmahal and Bakhtiari (21.1%), Tehran (20.5%), Isfahan (20.3%), Mazandaran (18.0%), and Kermanshah (12.5%). Of all FMS cases, 74.7% (1308 cases) were female and 25.3% (442 cases) were male. FMS occurrence was much more common in females than males (P-value = 0.001). Further, the mean age at onset was 30 years among FMS cases. A substantially higher probability of relapsing-remitting MS and secondary-progressive MS was found among FMS cases than sporadic MS (SMS) (P_value = 0.001). There was no significant difference in Expanded Disability Status Scale (EDSS) scores between FMS and SMS. The majority of FMS cases were observed among first-degree relatives, with the highest rate in siblings. There was a significant association between MS risk and positive familial history in both maternal and paternal aunt/uncle (P_value = 0.043 and P_value = 0.019, respectively). Multiple sclerosis occurrence among offspring of females was higher than males (P_value = 0.027).

Conclusions

In summary, our findings imply a noteworthy upward trend of FMS in Iran, even more than the global prevalence, which suggests a unique Atlas of FMS prevalence in this multi-ethnic population. Despite the highest rate of FMS within Persian and Lor ethnicities, no statistically significant difference was observed among the provinces.

Virtual Reality-Based Therapy Improves Fatigue, Impact, and Quality of Life in Patients with Multiple Sclerosis. A Systematic Review with a Meta-Analysis

Patients with multiple sclerosis (PwMS) have a high level of fatigue and a reduced quality of life (QoL) due to the impact of multiple sclerosis (MS). Virtual reality-based therapy (VRBT) is being used to reduce disability in PwMS. The aim of this study was to assess the effect of VRBT on fatigue, the impact of MS, and QoL in PwMS. Methods: A systematic review with meta-analysis was conducted through a bibliographic search on PubMed, Scopus, Web of Science, and PEDro up to April 2021. We included randomized controlled trials (RCTs) with PwMS that received VRBT in comparison to conventional therapy (CT) including physiotherapy, balance and strength exercises, and stretching or physical activity, among others; or in comparison to simple observation; in order to assess fatigue, MS-impact, and QoL. The effect size was calculated using Cohen’s standardized mean difference with a 95% confidence interval (95% CI). Results: Twelve RCTs that provided data from 606 PwMS (42.83 ± 6.86 years old and 70% women) were included. The methodological quality mean, according to the PEDro Scale, was 5.83 ± 0.83 points. Our global findings showed that VRBT is effective at reducing fatigue (SMD −0.33; 95% CI −0.61, −0.06), lowering the impact of MS (SMD −0.3; 95% CI −0.55, −0.04), and increasing overall QoL (0.5; 95% CI 0.23, 0.76). Subgroup analysis showed the following: (1) VRBT is better than CT at reducing fatigue (SMD −0.4; 95% CI −0.7, −0.11), as well as in improving the mental dimension of QoL (SMD 0.51; 95% CI 0.02, 1); (2) VRBT is better than simple observation at reducing the impact of MS (SMD −0.61; 95% CI −0.97, −0.23) and increasing overall QoL (SMD 0.79; 95% CI 0.3, 1.28); and (3) when combined with CT, VRBT is more effective than CT in improving the global (SMD 0.6, 95% CI 0.13, 1.07), physical (SMD 0.87; 95% CI 0.3, 1.43), and mental dimensions (SMD 0.6; 95% CI 0.08, 1.11) of QoL. Conclusion: VRBT is effective at reducing fatigue and MS impact and improving QoL in PwMS.