Background

Multiple sclerosis (MS) is a chronic degenerative neurological disease that has been an increasing prevalence in many countries all over the world. Tehran province is the most populated and capital province in Iran with an increasing MS prevalence.

Objectives

The present study is conducted to estimate the prevalence and assess the epidemiology of MS including familial MS history in Tehran in 2019.

Methods

A cross-sectional study was conducted based on information taken by Iranian MS Society (IMSS) registry system from 1999 to 2019 in Tehran Province, the capital of Iran. All diagnosis approved by neurologists with MS fulfilling McDonald criteria. Individually person fills out a questionnaire relating to baseline characteristic data such as sex, age, familial history of MS and its degree of family and age at disease onset.

Results

A total of 22421 cases were registered at this study, 24.9% were male and 75.1% were female (female/male ratio = 3.016). The mean age of disease onset was 28.92 (SD=8.74). The crude prevalence of MS in 2019 in Tehran was 162.39 cases per 100000 people (244.92 per 100000 in females and 80.58 per 100000 in males). Generally, 469 (6.5%) of cases were below 18 years old, and 10903 patients (48.62%) were between 18 and 40 years old.

Totally, 2982 subjects (13.7%) had a positive family history of MS; among them, 1279 cases (42.58%) with positive family history in their first degree, 471 (15.82%) in their second degree and 896 (30.11%) subjects with positive family history in their third degree family members.

Conclusions

MS is more prevalent among female and young people.

MS prevalence in Tehran has increased (comparing to previous studies) and Tehran is one of the counties with highs prevalence in Asia.