Is the sharp increasing trend of multiple sclerosis incidence real in Iran?

Prevalence of Multiple Sclerosis in Vitiligo Patients and Their First-Degree Relatives: Two Diseases with Similarities in Pathogenesis and Treatment

INTRODUCTION

Vitiligo is a common pigmentation disorder manifested by white macules and patches. It is accompanied by some autoimmune and neurological diseases. Recently, it has been suggested that multiple sclerosis (MS) is more common in vitiligo patients and that they have a higher risk of developing MS during their lifetime.

OBJECTIVES

In this study, we aimed to determine the prevalence of MS in patients with vitiligo and their first-degree relatives and compare it with the prevalence in the population.

METHODS

In this cross-sectional study, data were consecutively collected from patients referred to Razi Hospital from March 2020 to December 2021.

RESULTS

Seven hundred and nine patients with vitiligo participated in this study, and 15 reported a history of MS (2.12%, 95% confidence interval [CI] 1.06%-3.17%). This rate was significantly higher than the prevalence of MS in the average population of Tehran (P < 0.001). Of the 2886 first-degree relatives of the patients, 10 had MS (0.35%, 95%CI 0.13&-0.56%), which was higher than the prevalence of MS, yet not statistically significant.

CONCLUSIONS

A significant association between vitiligo and MS was observed, which should be of clinical and therapeutic importance. However, the prevalence of MS in first-degree relatives of vitiligo patients was higher than the average rate, yet not statistically significant.

The prevalence and incidence of multiple sclerosis over the past 20 years in northern Japan

OBJECTIVES

The prevalence of multiple sclerosis (MS) in East Asia is thought to be lower than in Western countries. Globally, there is a trend of increasing MS prevalence. We investigated the changes in the prevalence and clinical phenotype of MS in the Tokachi province of Hokkaido in northern Japan, from 2001 to 2021.

METHODS

Data processing sheets were sent to all related institutions inside and outside the Tokachi area of Hokkaido island in Japan and were collected from April to May 2021. The prevalence according to the Poser's diagnostic criteria for MS was determined on March 31, 2021.

RESULTS

In 2021, the crude MS prevalence in northern Japan was 22.4/100,000 (95% confidence interval, 17.6-28.0). The prevalences of MS standardized by the Japanese national population in 2001, 2006, 2011, 2016, and 2021 were 6.9, 11.5, 15.3, 18.5, and 23.3, respectively. The female/male ratio was 4.0 in 2021, increased from 2.6 in 2001. We checked the prevalence using the 2017 revised McDonald criteria, and found only additional male patient who had not fulfilled Poser's criteria. The age- and sex-adjusted incidence of MS per 100,000 individuals increased from 0.09 in 1980-1984 to 0.99 in 2005-2009; since then, it has remained stable. The proportions of primary-progressive, relapsing-remitting, and secondary-progressive MS types in 2021 were 3%, 82%, and 15%, respectively.

CONCLUSION

Our results demonstrated a consistent increase in the prevalence of MS among the northern Japanese over 20 years, particularly in females, and consistently lower rates of progressive MS in northern Japan than elsewhere in the world.

Multiple sclerosis incidence temporal trend in the Northeast of Iran: Using the Empirical Bayesian method

BACKGROUND

In recent years dramatic changes in multiple sclerosis (MS) incidence have been reported in different provinces in Iran. This study was conducted to assess MS incidence temporal trends from March 21, 2005, to March 20, 2020, and provide a forecast until the end of 2025 in Shahroud county.

METHODS

This longitudinal study was carried out based on the data obtained from the MS registration system in Shahroud county. First, the annual incidence rates were calculated based on the year of diagnosis and smoothed using the Empirical Bayesian Method. Then temporal trends and annual percent change (APC) of MS incidence were analyzed using Joinpoint (JP) regression. Finally, the univariate time series model analysis was used to estimate the MS incidence trend until the end of 2025.

RESULTS

A total of 234 newly diagnosed cases (60 [25.64%] males and 174 [74.36.4%] females) were examined in this study. The mean age of patients at the time of diagnosis was 31.40 ± 3.78. It was 32.01 ± 6.35 and 30.66 ± 4.27 years for males and females, respectively (P<0.22). The mean annual MS incidence was 5.99 ± 1.46, 3.03 ± 0.21, and 8.98 ± 2.79 per 100,000 in overall, males and females respectively. The MS incidence increased significantly from 5.67 (95% CI: 3.63-7.99) in 2005 to 7.58 (95% CI: 5.17-10.28) in 2020 with an APC of 4.5 (2.8 - 6.1). The MS incidence had a non-linear time trend in the study period and the best time trend fitted to the annual MS incidence trend was the non-linear quadratic curve. Based on this model, the annual MS incidence is expected to increase until the end of 2025.

CONCLUSION

Shahroud county is one of the high-risk areas for MS and the increasing trend of MS incidence in it is similar to regional and global changes. This study, also, showed that MS incidence in Shahroud county will be increasing in the coming years.

Short quality of life scale: A cross-cultural validation in Iranian patients with multiple sclerosis

Health-related quality of life (HRQoL) is the prioritized measure in multiple sclerosis (MS) patients. The short quality of life scale (SQoL) developed by Devy et al. (2013) is an MS-specific and abbreviated scale with ten items suitable for routine medical care settings. The current study reported the cross-cultural validation of the scale in the Persian language. A total of 455 convenient MS patients with a mean age of 38.39 (9.28) ranged from 18 to 64 filled out the primary measure and the validating measures, including hospital anxiety and depression scale, visual analogue scale - quality of life, and a single index of the number of past-year MS relapse. The confirmatory factor analysis on original structure indicated an acceptable model fit. However, a modestly modified structure composing of physical-functional dimension (items #1-3), mental dimension (items #5-8), and pain & energy dimension (items 4 & 9,10) was also exposed with a sound fit and a meaningful structure. The overall internal consistency reliability was sound (0.88), and the concurrent validity was confirmed. The Persian short quality of life scale (P-SQoL) is the first translated and validated version of the scale, surfacing significant implications. Further cross-cultural investigations are recommended to re-examine current findings. The classic and recent suggestions concerning the close interplay between the immunity system and the psychological system and the implications based on Iran's context are discussed.

Temporal Incidence and Prevalence Trends of Multiple Sclerosis in Markazi Province, Iran

BACKGROUND

The epidemiology of multiple sclerosis (MS) exhibits significant variability all over the world. Additionally, the incidence and prevalence of the disease are geographically diverse in the different provinces of Iran.

OBJECTIVES

Due to the lack of a research about the epidemiology of MS in the Markazi province of Iran, the present study aimed to estimate its prevalence and incidence in this province.

METHODS

This cross-sectional register study was conducted according to the data related to the MS Society of Markazi province. The inclusion criteria were definite MS during 2010-2019, residence in Markazi province, and membership in the MS society of Markazi province. The annual incidence and prevalence of MS (per 100,000 person-years) were computed by sex and age groups. Further, age-standardized prevalence and incidence rates were calculated based on the Iranian population. A gamma regression model with log link was utilized for comparing the rates over time statistically. The prevalence and incidence rates were computed by using Excel, and R 4.0.5 was applied to fit the gamma model.

RESULTS

In the study, the total number of MS cases was 1,391, among whom 1,098 (78.9%) and 293 (21.1%) were females and males, respectively. The onset of MS occurred at the mean (S.D) age of 31.76 (8.98) years with a female/male ratio of 3.75. During the study period (2010-2019), the incidence rate of the disease was on the decline, while the prevalence rate elevated, by indicating a rising trend in MS prevalence in both sexes.

CONCLUSION

The results represented the decreasing and increasing trend of the incidence and prevalence of MS in Markazi province over the recent years. The province is one of the regions with a high prevalence and incidence rate of MS compared to the national and global statistical data.

Temporal trends of incidence and prevalence of multiple sclerosis in Razavi Khorasan Province, Northeast Iran

OBJECTIVES

The prevalence of multiple sclerosis (MS) in the Persian Gulf countries has been significantly increasing during the past decades. This study was conducted for investigating the prevalence and incidence of MS in Northeast Iran (Khorasan Razavi province).

METHODS

This cross-sectional study was conducted during 1 January 1988 and 23 September 2018. All patients with a clinically definite diagnosis of MS according to the McDonald criteria (2005) and MRI along with the medical diagnosis, recorded in the Khorasan MS society, were considered for calculation of crude and age-standardized prevalence, and incidence rates of MS. The periodic incidence rates were calculated based on the year of onset of MS. Also, we calculated gender ratios for prevalence and incidence rates.

RESULTS

The mean age-standardized prevalence and incidence rates of MS in the Khorasan Razavi were 8.69 (95% CI 8.05-9.41) per 100,000 (3.99 (95% CI 3.39-4.74) for males, 13.49 (95% CI 12.37-14.76) for females). Age-standardized prevalence was 48.87 (95% CI 48.37-49.35) per 100,000 (22.47 (95% CI 22.01-22.93) for males, 75.65 (95% CI 74.80-76.51) for females). Also, the mean incidence and prevalence for Mashhad County as capital of province were 11.38 and 59.09 per 100,000 populations, respectively. The female/male ratio was 3.33 for all age groups.

CONCLUSION

Our results showed that this region is a high-risk area for MS like central region of Iran. Our results revealed that the prevalence and incidence of MS in the study area have increased during the recent decades with a sharp slope.