Prevalence of multiple sclerosis (MS) in Iran: a systematic review and meta-analysis.

BACKGROUND Prevalence of multiple sclerosis (MS) is increasing world-wide. Iran is not exception. As the prevalence reported differently in various provinces, we designed this systematic review and meta-analysis to estimate pooled prevalence of MS in Iran. METHODS Two researchers systematically searched Scientific Information Database (SID), PubMed, Scopus, EMBASE, Web of Science, and google scholar. They also searched references of the included studies, and conference abstracts which were published up to April 2021. The search strategy included the MeSH and text words as ((((Multiple Sclerosis OR Sclerosis, Multiple) OR Sclerosis, Disseminated) OR Dis-seminated Sclerosis) OR MS (Multiple Sclerosis)) OR Multiple Sclerosis, Acute Fulminating)) AND (prevalence OR prevalences OR period prevalence OR prevalence, period OR point prevalence OR point prevalences OR prevalence, point) AND (Iran OR Islamic Republic of Iran)))). RESULTS The literature search revealed 2817 articles, after deleting duplicates 2184 remained. For the systematic review, 34 studies were included. The prevalence is highest in Tehran and lowest in Khuzestan and Sistan-Baluchestan provinces. The pooled prevalence was 0.001 (95% CI: 0.000-0.001) (I2=0, P<0.001). CONCLUSION The results of this study show that the pooled prevalence of MS in Iran is 100 in 100,000 which is high. The prevalence in provinces increases dramatically.