Determining Prevalence of Depression and Covariates of Depression in a Cohort of Multiple Sclerosis Patients.

Background: Depression is one of the most common symptoms experienced by multiple sclerosis patients and may be secondary to the disease itself as well as other variables such as age, disease severity and side effects of treatment. Objective: To determine if there is an association between disease modifying therapies and depression rates based on PHQ9 scores in multiple sclerosis. Methods: This was a retrospective chart review. Patients followed at the University of Texas Southwestern Multiple Sclerosis and Neuroimmunology Clinic from 2017 to 2020 were included in this study. Patients' most recent PHQ-9 scores were used. The following data was extracted from patient charts: disease modifying therapy, age, disease duration, gender, antidepressant use and ambulatory status. Results: Data from our study included 2611 individual PHQ-9 scores. The majority of our patients were female and the mean age across all treatment groups was 50.37 years old. The median disease duration across all treatment groups was 12.74 years. Most patients in this cohort required no ambulatory assistance. 43.86% of patients were on antidepressants and use was correlated with a higher PHQ9 score. The median PHQ 9 score across all treatment groups was 4 (Interquartile range = 7). Across treatment groups, patients on interferon therapy had the lowest PHQ 9 scores with a median of 2. Conclusions: Our study demonstrated that there were lower PHQ-9 scores among interferon treatment group as compared to other disease modifying therapies and non-treatment groups.