Abstract

Aim: This study aimed to describe the incidence and analyze the most relevant demographic, clinical, diagnostic, epidemiological and treatment characteristics; as well as the presence of known risk and prognostic factors, in Costa Rican patients with Multiple Sclerosis attended in three hospitals and included in the international initiative ENHANCE.

Methods: This observational study, a retrospective analysis of medical record information of MS patients aged 18 and older who received follow up in three hospitals of the Costa Rica's national health care system, Caja Costarricense de Seguro Social (Hospital San Juan de Dios, Hospital San Rafael de Alajuela and Hospital San Carlos), between January 2014 and December 2019. All cases were used to determine the clinical and sociodemographic characteristics, only new cases were considered for incidence calculations and clinical and treatment outcomes were obtained from a patient subset that had active follow- up for at least 5 years.

Results: A total of 147 cases were identified, of which 72 were new cases during the study period, and 75 were incident or prevalent cases at 2014 with documented follow-up of at least 5 years. The average age at the onset of symptoms was 31.9 years, and 35.0 at the moment of diagnosis. A predominance of female cases was observed (69.4%, n=102), patients exhibited variable scores on the Expanded Disability Status Scale, ranging from 0 to 8.5 and the annual incidence in the analyzed population varied between 0.32 and 1.28 cases per 100.000 inhabitants. The main clinical form identified was relapsing-remitting (87.8%, n=129), with motor and sensory impairments being the primary affectations. Periventricular lesions (35%, n=45), were the most frequent documented in magnetic resonance imaging, and the majority of patients presented low levels of vitamin D. Regarding therapeutic management, there was a decrease in the use of traditional treatments (commonly referred to as first-line) and an increase in the use of new or second-line alternatives, such as ocrelizumab and natalizumab.

Conclusion: The data obtained in this study suggests that the analyzed population shows similar features to what has been reported in other internationally conducted studies and does not differ significantly from what has been previously described for the country.

Keywords: Multiple sclerosis; Central America and the Caribbean; incidence; diagnosis; clinical features; treatment.