Epidemiology of multiple sclerosis in Iraq: retrospective review of 4355 cases and literature review

Objectives Multiple sclerosis (MS) is a progressive demyelinating and degenerative disease of the CNS, which is highly variable geographically. The objectives are to establish comprehensive nationwide MS epidemiological data and compare it with similar studies conducted in regional and international communities. To the best of our knowledge, this is the first nationwide comprehensive epidemiological study conducted in Iraq. Methods This retrospective study is including 4355 MS cases from the 10 officially authorized MS clinics in Iraq from January 2000 to December 2018. All cases were diagnosed according to McDonald's criteria 2010, new cases diagnosed according to the new criteria of McDonald's criteria 2018. All patients' records were reviewed by the scientific committee. Results Our study found that 68.51% of MS were females with female-to-male ratio 2.18:1 and 4.07% of patients were diagnosed before they reached 18 years of age. The mean age was 32.3 +/- 9.8. The prevalence was found to be 11.73/100,000; it was 16.2/100,000 among females and 7.3/100,000 among males. The incidence was 0.05 in the year 2000 and 1.5 in the year 2017. Initial symptoms were visual 32.06%, motor 28.11%, and 25.58% were sensory symptoms, and 89.97% of the clinical form was relapsing/remitting MS (RRMS) and 81.65% of patients were on first-line treatment. Meanwhile, 66.97% of cases were diagnosed within weeks or months from symptom onset. Summer had the most frequencies regarding birth season. Conclusions MS has a significantly increased incidence in Iraq, while prevalence is low compared to neighboring countries. RRMS was the most common clinical form and visual symptoms showed the highest frequency of the first presenting symptoms.