Sex ratio in multiple sclerosis mortality over 65 years; an age-period-cohort analysis in Norway

BCG vaccination and multiple sclerosis risk: A Norwegian cohort study

INTRODUCTION

Bacillus Calmette-Guérin (BCG) vaccination induces long-lasting effects on the adaptive and innate immune systems and prevents development of experimental autoimmune encephalomyelitis and possibly also inflammatory disease activity in multiple sclerosis (MS).

OBJECTIVE

The objective is to examine if BCG given in early adulthood decreases MS risk.

METHODS

From 791,369 (52% females) Norwegians participating in a national tuberculosis screening program from 1963 to 1975, we collected information on BCG vaccination and tuberculosis disease status. Later, MS disease was ascertained through both the Norwegian MS Registry and Biobank and the Norwegian Death Registry. We used logistic regression models to assess the relationship between BCG vaccination and MS risk.

RESULTS

In those BCG vaccinated, mean age at vaccination was 15.6 (standard deviation (SD) = 5.5) years. A total of 2862 (65% females) MS cases were retrieved. Overall, we found no association between MS risk and BCG vaccination. Compared to non-BCG-vaccinated individuals with no signs of tuberculosis infection, odds ratio (OR) for MS was 1.00 (95% confidence interval (CI) = 0.80-1.25) in the BCG-vaccinated group. In those not BCG vaccinated because of latent tuberculosis infection, the corresponding OR was 0.86 (95% CI = 0.66-1.13).

CONCLUSION

We found no evidence of BCG vaccination or latent tuberculosis infection in young adulthood being linked to MS risk.

Global, regional, and national burden of multiple sclerosis from 1990 to 2019: Findings of global burden of disease study 2019

BACKGROUND

The global rising prevalence and incidence of multiple sclerosis (MS) has been reported during the past decades. However, details regarding the evolution of MS burden have not been fully studied. This study aimed to investigate the global, regional, and national burden and temporal trends in MS incidence, deaths, and disability-adjusted life years (DALYs) from 1990 to 2019 using the age-period-cohort analysis.

METHODS

We performed a secondary comprehensive analysis of incidence, deaths, and DALYs of MS by calculating the estimated annual percentage change from 1990 to 2019 obtained from the Global Burden of Disease (GBD) 2019 study. The independent age, period, and birth cohort effects were evaluated by an age-period-cohort model.

RESULTS

In 2019, there were 59,345 incident MS cases and 22,439 MS deaths worldwide. The global number of incidences, deaths, and DALYs of MS followed an upward trend, whereas the age-standardized rates (ASR) slightly declined from 1990 to 2019. High socio-demographic index (SDI) regions had the highest ASR of incidences, deaths, and DALYs in 2019, while the rate of deaths and DALYs in medium SDI regions are the lowest. Six regions which include high-income North America, Western Europe, Australasia, Central Europe, and Eastern Europe had higher ASR of incidences, deaths, and DALYs than other regions in 2019. The age effect showed that the relative risks (RRs) of incidence and DALYs reached the peak at ages 30-39 and 50-59, respectively. The period effect showed that the RRs of deaths and DALYs increased with the period. The cohort effect showed that the later cohort has lower RRs of deaths and DALYs than the early cohort.

CONCLUSION

The global cases of incidence, deaths, and DALYs of MS have all increased, whereas ASR has declined, with different trends in different regions. High SDI regions such as European countries have a substantial burden of MS. There are significant age effects for incidence, deaths, and DALYs of MS globally, and period effects and cohort effects for deaths and DALYs.

Potential biological contributers to the sex difference in multiple sclerosis progression

Multiple sclerosis (MS) is an immune-mediated disease that targets the myelin sheath of central nervous system (CNS) neurons leading to axon injury, neuronal death, and neurological progression. Though women are more highly susceptible to developing MS, men that develop this disease exhibit greater cognitive impairment and accumulate disability more rapidly than women. Magnetic resonance imaging and pathology studies have revealed that the greater neurological progression seen in males correlates with chronic immune activation and increased iron accumulation at the rims of chronic white matter lesions as well as more intensive whole brain and grey matter atrophy and axon loss. Studies in humans and in animal models of MS suggest that male aged microglia do not have a higher propensity for inflammation, but may become more re-active at the rim of white matter lesions as a result of the presence of pro-inflammatory T cells, greater astrocyte activation or iron release from oligodendrocytes in the males. There is also evidence that remyelination is more efficient in aged female than aged male rodents and that male neurons are more susceptible to oxidative and nitrosative stress. Both sex chromosome complement and sex hormones contribute to these sex differences in biology.

Standardized mortality ratios in multiple sclerosis: Systematic review with meta-analysis

OBJECTIVE

To perform a meta-analysis of all-cause, cause-specific and gender-specific standardized mortality ratio and crude mortality rate for people with multiple sclerosis. We also examined the temporal trends in this data.

METHODS

Medline, Cochrane Library and Scopus were searched. Keywords were "multiple sclerosis" and "standardized mortality ratio" or "Standardized Mortality Ratio". We included longitudinal studies with available data on the number of deaths, follow-up period, person years and reports of standardized mortality ratio (SMR). Crude mortality ratio (CMR) was calculated and SMR was extracted. CMRs and log-SMR were pooled by the method of inverse variance. Meta-regression models were used to investigate temporal trends.

RESULTS

Fifty-seven articles were screened. Fifteen studies were included covering a period 1949-2013 (160,000 patients; 21,225 deaths). The all-cause SMR for people with MS was 2.61 (95% CI 2.58 to 2.65). For men this was 2.47 (95% CI 2.42 to 2.52) and for women 2.57 (95% CI 2.53 to 2.61). The CMR was 13.45/1000 person years. Cause-specific SMR was 1.74 (1.67 to 1.81) for CVD, 4.70 (4.45 to 4.87) for respiratory disease and infection, 1.81 (1.64 to 2.0) for accident and suicide and 0.99 (0.93 to 1.06) for cancer. Meta-regression analysis of the SMR compared to midpoint follow-up year revealed no relationship (co-efficient 0.001, p = .98).

CONCLUSIONS

People with multiple sclerosis (MS) have reduced overall survival and increased risk of death from cardiovascular, respiratory and infectious disease as well as accidents and suicide. This does not appear to have changed over the last 65 years.

Age-period-cohort analysis of the incidence of multiple sclerosis over twenty years in Lorraine, France

Multiple sclerosis (MS) is a neurodegenerative disease of the central nervous system. An increase in MS incidence over time is reported in several regions of the world. We aimed to describe the evolution of the annual MS incidence in the Lorraine region, France, from 1996 to 2015 and to analyze potential components of a possible change by a temporal effect of age at MS onset, MS onset period, and birth cohort, overall and for each sex. Cases were identified from ReLSEP, a population-based registry of MS cases living in Lorraine, northeastern France, with MS onset between 1996 and 2015. Age-period-cohort modeling was used to describe trends in MS incidence. Annual age- and sex-standardized incidences were relatively stable: 6.76/100 000 population (95%CI [5.76-7.91]) in 1996 and 6.78/100 000 (95%CI [5.72-7.97]) in 2015. The incidence ratio between women and men was 2.4. For all time periods, the peak incidence occurred between ages 25 and 35 years. Age-period-adjusted cohort and age-cohort-adjusted period analyses did not reveal a period or cohort effect. The incidence of MS remained stable over the study period in Lorraine, and we could not identify any particular effect of disease onset period or birth period on this evolution.

Case Report: Antibodies to the N-Methyl-D-Aspartate Receptor in a Patient With Multiple Sclerosis

The association between multiple sclerosis and anti-N-Methyl-D-Aspartate receptor encephalitis is limited to merely a few case reports, and the exploration of the pathogenic mechanisms underlying the overlap of these two disease entities is very limited. Therefore, case reports and literature review on N-Methyl-D-aspartate receptor antibody in patients with multiple sclerosis are unusual and noteworthy. A young female had the first episode of paresthesia and motor symptoms with positive anti-N-Methyl-D-Aspartate receptor antibody and recovered after immunotherapy, and at the first relapse, the patient developed disorders of consciousness with positive anti-N-Methyl-D-Aspartate receptor antibody, findings of magnetic resonance imaging showed features of autoimmune encephalitis, which was also controlled by immunotherapy. At the second relapse, anti-N-Methyl-D-Aspartate receptor antibody turned negative while oligoclonal bands presented positive, and findings of magnetic resonance imaging showed features of multiple sclerosis. Afterwards, we followed the patient after receiving disease modifying treatment to monitor the efficacy and safety of teriflunomide. Based on literature review, demyelinating diseases patients with anti-neuronal antibody have complex, diverse and atypical symptoms; therefore, high attention and increased alertness are necessary for neurologists. Conclusively, anti-neuronal antibody may present in many neuroinflammatory conditions, and diagnostic criteria should be used with caution if the clinical presentation is atypical, and neurologists should not rely excessively on laboratory tests to diagnose neurological diseases. Timely and comprehensive examination and consideration as well as early standardized treatment are the key factors to reduce patient recurrence and obtain a good prognosis.

SeXX Matters in Multiple Sclerosis

Multiple sclerosis (MS) is the most common chronic inflammatory and neurodegenerative disease of the central nervous system (CNS). An interesting feature that this debilitating disease shares with many other inflammatory disorders is that susceptibility is higher in females than in males, with the risk of MS being three times higher in women compared to men. Nonetheless, while men have a decreased risk of developing MS, many studies suggest that males have a worse clinical outcome. MS exhibits an apparent sexual dimorphism in both the immune response and the pathophysiology of the CNS damage, ultimately affecting disease susceptibility and progression differently. Overall, women are predisposed to higher rates of inflammatory relapses than men, but men are more likely to manifest signs of disease progression and worse CNS damage. The observed sexual dimorphism in MS may be due to sex hormones and sex chromosomes, acting in parallel or combination. In this review, we outline current knowledge on the sexual dimorphism in MS and discuss the interplay of sex chromosomes, sex hormones, and the immune system in driving MS disease susceptibility and progression.

Mortality trend for multiple sclerosis in Italy during the period 1980-2015

BACKGROUND

The epidemiology of Multiple Sclerosis (MS) is relevant for health-services planning. Most of MS prevalence and incidence studies in Italy referred to specific geographical areas and periods, whereas mortality data are routinely collected at the national level. The aim was to assess MS mortality trend and geographical differences in Italy from 1980 to 2015.

METHODS

Mortality data were provided by the Italian Institute of Statistics. Due to a low number of annual deaths, mortality data were analysed for both the entire period under study and for sub-periods. Temporal trends were first evaluated using age-adjusted mortality rates (AMRs) comparing each sub-period with the initial one. Then, the annual percent change in mortality was estimated through the joinpoint regression model. Spatial differences between 5 main geographical areas were evaluated using standardized mortality ratios (SMRs).

RESULTS

During the study period, 4,959 deaths for males and 7,434 for females were observed. The higher overall AMR was observed for females (F:0.71 vs. M: 0.56 per 100,000 persons per year). Analysing mortality by gender and geographical area, SMRs 〈 100 were observed in South Italy for both sexes, and in Central Italy for males only, whereas SMRs 〉 100 for Islands for both sexes, and in North-East and North-West for females only. The analysis of the mortality trend through AMRs calculated for sub-periods revealed no difference between the first and the last period for males, whereas a significant increase in mortality was observed for females. The joinpoint regression analysis showed a significant decrease in mortality up to 1995 for males (APC -3.23%) and up to 1999 for females, (APC -1.01%), followed by a significant increase for both sexes, but more marked for females (APC +1.9% M, +2.34% F).

CONCLUSION

The increasing trend of mortality for MS, especially for females, may reflect the increase in the prevalence of MS and the improvement in the quality of diagnosis or coding of the cause of death.

The changing course of multiple sclerosis: rising incidence, change in geographic distribution, disease course, and prognosis

PURPOSE OF REVIEW

This review provides a brief update of new research findings on the changing epidemiology, disease course, and prognosis of multiple sclerosis (MS).

RECENT FINDINGS

Evidence not only continues to support the female predominance in incidence and prevalence of the disease but also supports an increase in incidence of MS in geographic areas that were previously considered to be low incidence for the disease.

SUMMARY

An increased interest in population-based registries and databases will provide more valid epidemiological measures and observational studies conducted in well-defined study populations. Such studies are crucial for an accurate description of both changing prognosis of MS and differential characteristics of the various MS phenotypes.