Background: Multiple sclerosis (MS) is one of the most common chronic immune-mediated diseases of the human central nervous system and an important cause of non-traumatic neurologic disability among young population in several countries. Recent reports from East Asia, South East Asia and South Asia have proposed a low to moderate prevalence of MS in these countries. Methods: A literature review search was carried out in December 2014 in Medline, Embase, Scopus and Cochrane library to recover original population-based studies on MS epidemiology in East Asia, South East Asia and South Asia countries published between January 1, 1950 and December 30, 2014. We intended search strategies using the key words: multiple sclerosis, prevalence, incidence and epidemiology. Based on our inclusion criteria, 68 epidemiologic studies were included in this systematic review. Results: The most extensively used diagnostic criteria in the studies were McDonald's criteria. Most studies were performed in a multi-center hospital setting. The female to male ratio varied and ranged from 0.7 in India to 9.0 in China. The mean age at disease onset ranged from the lowest age of 25.3 in Iran to the highest age of 46.4 in China. MS prevalence ranged from 0.77 in 100,000 populations in Hong Kong (1999) to 85.80 in 100,000 in Iran (2013). Conclusions: Advances in MS registries around the globe allow nationwide population-based studies and will allow worldly comparisons between the prevalence and incidence in different regions that are provided to monitor estimation.

Background: The epidemiological characteristics of multiple sclerosis (MS) have been investigated in various studies, which have revealed that the prevalence of MS varies across countries. The present study was conducted to investigate the longitudinal prevalence of MS in Tehran, Iran. Methods: The present population-based study was conducted in Tehran, the capital of Iran from 1999 to 2018 based on the annual report data provided by the Iranian MS Society (IMSS) registry system. The age-standardized and crude prevalence were estimated using population data presented by the Statistical Centre of Iran. Results: A total of 21,580 MS cases were registered and included in the analysis. Among the participant patients, 24.99% (5393) and 75.01% (16,187) of cases were male and female, respectively. The mean age of MS onset was 28.8 years (S.D: 8.7). The age-standardized prevalence (ASP) of MS increased from 73.7 (95%CI: 72.1–75.2) per 100,000 people in 2006 to 137.6 (95% CI: 135.7–139.5) per 100,000 people in 2018. The ASP of MS in 2018 was estimated to be 67.9 (95%CI: 66.0–69.8) and 207.3 (95%CI: 204.0–210.7) per 100,000 people among males and females, respectively. The age-standardized female-to-male ratio of MS ranged from 3.7 (in 2010) to 2.06 (in 2017). Conclusion: The findings of this study suggested that the prevalence of MS in Tehran province is relatively high, and the occurrence of the disease is more common in the age groups under 40 years as compared with older-aged groups. In line with reports provided for various regions of the world, the prevalence of MS was higher among women. Similarly, the findings of this study revealed that the female-to-male ratio was 2.14 in 2018.

Tehran is the capital of Iran with an increasing multiple sclerosis (MS) prevalence. A retrospective population-based study was conducted to evaluate the trends of MS prevalence in Tehran. A population-based survey was conducted for the period 1999 to 2015, based on Iranian MS Society (IMSS) registry system of Tehran, the capital city of Iran. Point regression analysis was applied on MS trend data to find annual percent change (APC). The logistic regression analysis was used to estimate the odds ratio (OR) for individual variables in order to assess factors associating with familial recurrence of MS. P values < 0.05 were considered significant. MS prevalence has significantly increased during the study period from 1999 to 2015 (56.22 per 100,000). Total point prevalence of MS was 115.94 per 100,000 persons in 2015 compared to general population. Positive family history of MS was observed among 12.4% of patients. The strongest association amongst first-degree relatives was found in siblings, p value ≤ 0.001. MS prevalence is rising in Tehran and this city is one of the regions with highest MS prevalence in Asia. In this sample, the largest proportion of relatives with MS were found among first-degree relatives, particularly siblings. Familial recurrence correlated with relative type.

The prevalence of Multiple Sclerosis (MS) has been increasing worldwide and the highest prevalence ratio among Asian countries was reported in Iran. This study aims to estimate the increase in MS occurrence during more than three decades in Tehran and forecast the future condition of the disease using time series approaches for the next ten years. The cross-sectional study was conducted from 1999 to 2019 based on records of MS cases from Iranian MS Society (IMSS) registry system. The prevalence was estimated using population data presented by the Statistical Centre of Iran. Through Bayesian Structural Time Series (BSTS) model, we want to predict the prevalence of familial and sporadic MS in the next ten years. . Among 22,421 cases with MS, 16,831 (75.1 %) were female and 5589 (24.9 %) were male. Female to male ratio was 3.0:1 and the number of familial MS cases were 2982 (13.3 %) of subjects. Female gender was less responsible for higher rate of MS in familial definition (beta = 0.020) in comparison to sporadic cases (beta = 0.034). Forecasting by BSTS revealed an increase in MS prevalence for the next ten years so that the prevalence rate for total, familial and sporadic MS respectively begins with 189.50 (183.94-195.14), 25.69 (24.97–26.45) and 163.74(159.06-168.57) in 2020 and ends with 220.84 (171.48-266.92), 30.79 (24.16–37.15), and 189.33(146.97-230.19) in 2029. According to the findings, MS prevalence increased during three decades and it will increase over the next ten years. Tehran province is one of the regions with highest MS prevalence in Asia. The results of present study indicated that females are at higher risk for MS than males in both sporadic and familial MS.