Assesment of common infection and malignancy in multiple sclerosis patients: a single-center cross-sectional study

OBJECTIVES: Multiple sclerosis (MS) is an autoimmune demyelinating disease of the central nervous system that causes nontraumatic disability in the young population[1]. The use of disease-modifying therapies (DMT) in MS increases the risk of infection and malignancy[2]. In clinical practice in MS, there is limited information about DMT, especially for the risk of infection and malignancy in the follow-up of patients. In our study, we examined the relationship between DMTs used infections and malignancies in MS patients. MATERIALS AND METHODS: This study was conducted as a single center, cross-sectional study between April 2021 and April 2023 at Karadeniz Technical University Faculty of Medicine, Department of Neurology. Demographic characteristics of the patients, MS-related information, last EDSS scores, comorbidities, charlson comorbidity index, hospitalization due to infection, and previous infection information were included in the study.The information included in the study was obtained by getting permission from the patients between April 2022 and April 2023 and the data of the patients were obtained from MSbase, hospital data registry database and a total of 3 questionnaires sent to the patients at 6 month periods (April 2022, October 2022 and April 2023), hospital visits and telephone interviews. OUTCOMES: Among the 509 patients included in the study, 342 (67.2%) were female and 167 (32.8%) were male. The number of RRMS was 472 (92.7%), SPMS was 30 (5.9%) and PPMS was 7 (1.4%). According to all-time hospitalization history in MS patients, SPMS was found to be 5.4 times more risky than RRMS. When the risk factors affecting hospitalization due to infection were examined throughout the study, it was found that an increase of 1 unit in the EDSS score increased the risk of hospitalization 1.8 fold. When the risk of urinary tract infection in MS patients was considered, it was found to be 3.3 fold higher in women and 6.8 fold higher in those with a history of hospitalization (all time), regardless of treatment. No significant association was found between treatment and the risk of all infections, skin-subcutaneous infections, intestinal infections, respiratory tract infections in MS patients. When risk factors for Covid-19 infection in MS patients were analyzed, it was found that SPMS patients were 2.9 times more risky than RRMS patients. When we analyze the results of univariate analysis of patients with Covid-19 infection and hospitalization history in MS patients, the risk of hospitalization due to infection increased 1.1 fold as the age increased, 2.8 fold as the number of comorbidities increased, 2 fold as the EDSS score increased, 9 fold for SPMS compared to RRMS, and 7.2 fold for natalizumab users compared to non users. In the study in terms of malignancy risk in MS patients, it was found that the presence of malignancy increased 6.2-fold as the Charlson comorbidity index increased and 1.8-fold as the EDSS score increased. RESULT: In conclusion, when the treatments received by MS patients were compared with each other, no significant relationship was found in terms of infection and malignancy risk. Infections requiring hospitalization were found to be increased in SPMS regardless of the treatment, and urinary tract infections were more common in women and in patients with a history of hospitalization.