Epidemiology of multiple sclerosis in Iran: A systematic review and meta-analysis

BACKGROUND: Multiple sclerosis (MS) is one of the most common neurological disorders and is one of the main causes of disability. The prevalence and incidence of MS in Iran is reported to range from 5.3 to 89/ 100,000and 7 to 148.1/ 100,000, respectively. There are no systematic and meta-analysis studies on MS in Iran. Therefore, this study was conducted to investigate the prevalence and incidence of MS in Iran using meta-analysis. METHOD: A systematic review of the present study focused on MS epidemiology in Iran based on PRISMA guidelines for systematic review and meta-analysis. We searched eight international databases including Scopus, PubMed, Science Direct, Cochrane Library, Web of Science, EMBASE, PsycINFO, Google Scholar search engine and six Persian databases for peer-reviewed studies published without time limit until May 2018. Data were analyzed using Comprehensive meta-analysis ver. 2 software. The review protocol has been registered in PROSPERO with ID: CRD42018114491. RESULTS: According to searching on different databases, 39 (15%) articles finalized. The prevalence of MS in Iran was estimated 29.3/ 100,000 (95%CI: 25.6–33.5) based on random effects model. The prevalence of MS in men and women was estimated to be 16.5/ 100,000 (95%CI: 13.7–23.4) and 44.8/ 100,000 (95%CI: 36.3–61.6), respectively. The incidence of MS in Iran was estimated to be 3.4/ 100,000 (95%CI: 1.8–6.2) based on random effects model. The incidence of MS in men was estimated to be 16.5/ 100,000 (95%CI: 13.7–23.4) and the incidence of MS in women was 44.8/ 100,000 (95%CI: 36.3–61.6). The meta-regression model for prevalence and incidence of MS was significantly higher in terms of year of study (p<0.001). CONCLUSIONS: The results of this study can provide a general picture of MS epidemiology in Iran. The current meta-analysis showed that the prevalence and incidence of MS in Iran is high and is rising over time.