The effect of body mass index on the morbidity and outcomes of COVID-19 in Iranian patients with multiple sclerosis

Background: It seems that patients with multiple sclerosis (MS) are at a higher risk for coronavirus disease 2019 (COVID-19) implications due to being subjected to immunomodulatory or immunosuppressive treatments. Besides, obesity as a risk factor may lead to more adverse consequences. The relationship between obesity and COVID-19 morbidity and outcomes in Iranian patients with MS still remains unclear. Methods: A cross-sectional study was conducted in Sina Hospital, Tehran, Iran. Patients with MS were asked to complete an online questionnaire in the Google Form format. Demographic information, clinical information including MS disease-related factors, COVID-19-related factors, and anthropometric information were recorded. Totally, 492 patients filled the questionnaire during two weeks in November 2021, by the response rate of 21.6%. Body mass index (BMI) was categorized based on the standard classification of the World Health Organization (WHO). The logistic regression was used to examine the risk of morbidity and chi-square test/one-way analysis of variance (ANOVA) was employed to determine the difference regarding severity and symptoms among groups. Results: In the fully adjusted model, the odds ratio (OR) of COVID-19 morbidity in class II obese participants was significantly 5.41 times higher than that in the normal BMI group [OR: 5.41, 95% confidence interval (CI): 1.00-29.09]. COVID-19 severity was significantly different among BMI groups (P = 0.024). Respiratory symptoms (P = 0.05) as well as gastrointestinal (GI) symptoms (P 0.01) of COVID-19 were more prevalent among class I and class II obese patients compared with overweight, normal weight, and underweight groups. Moreover, no one in the class I and class II obesity groups reported COVID-19 morbidity without any symptoms (P = 0.04). Conclusion: The results of the current study support the view that obesity could play a key role in susceptibility to COVID-19 morbidity and severity of the symptoms in patients with MS. The findings recommended that neurologists pay more attention to patients’ BMI during this pandemic.