Prevalence of multiple sclerosis in the Region of Murcia

Introduction. Multiple sclerosis (MS) is a demyelinating inflammatory disease of the central nervous system with immune-mediated pathogenesis. Recent research points to an increase in its prevalence, and a number of studies relate EpsteinBarr virus (EBV) with its aetiology. Aims. This study seeks to analyse the prevalence of MS in the Region of Murcia, and includes a description of the clinical characteristics at the time of onset of the disease, and of the EBV serological status of patients with MS. Patients and methods. We conducted a retrospective epidemiological study based on a sample consisting of the population living within the central-west healthcare area of the Region of Murcia (257,865 inhabitants). Clinical and serological data extracted from different sources were analysed. Results. Prevalence of MS in the population under study: 88 cases/100,000 inhabitants. Prevalence of MS together with isolated demyelinating syndrome: 98.4 cases/100,000 inhabitants. Mean incidence of MS: 5.8 cases/100,000 inhabitants/ year. At the onset of MS, 67.8% were females, 81.9% presented a relapsing-remitting course, the mean age was 31.4 years, the sensory system was the most frequently compromised (45.1%), onset was monofocal in 55.4% and the degree of disability on the Expanded Disability Status Scale was 2.1 points. The seroprevalence of EBV was 99.3%. The reactivation of EBV infection was related to the clinical activity of MS in 10 patients (45.4%). Conclusions. Currently, the prevalence of MS in the Region of Murcia is similar to that estimated in other Spanish autonomous regions. The study confirms the trend of increased prevalence observed over the last few decades.