Anxiety and Depression in Multiple Sclerosis: prevalence and associated factors

Introduction: Multiple Sclerosis (MS) is an inflammatory, autoimmune and demyelinating disease. Comorbidities such as anxiety and depression, by themselves, can lead to cognitive deficits and their presence associated with MS can have impacts on the patient's quality of life and their symptoms. 

Objective: To evaluate the prevalence of anxiety and depression in patients diagnosed with MS. To investigate the impact of these comorbidities on physical disability and cognitive scales.

Methods: This is an observational, cross-sectional, retrospective and single center study. The Hospital Anxiety and Depression Scale (HADS) was applied to determine the prevalence of the aforementioned comorbidities. A score of ≥8 on each of the HADS sub scores were used to define a clinically meaningful anxiety or depression disorder. Statistical associations were performed with the Expanded Disability Status Scale (EDSS), the Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS), the Modified Fatigue Impact Scale (MFIS), and the Multiple Sclerosis Impact Scale (MSIS-29).

Results: A total of 99 subjects were included in the study (77.8% female, mean age 39.8 ± 10.6 years, mean disease duration 9.5 ± 7.3 years). Anxiety and depression were identified in 51 (51.5%) and 39 (39.4%) of patients respectively. Median/Interquartile scores for anxiety and depression were respectively 8/(4-12) and 6/(3-10). Patients with anxiety and depression had a higher fatigue score (MFIS) (p<0.001) and a higher MSIS-29 score (p<0.001). Other scales such as EDSS and all BICAMS tests showed no differences between patients with and without anxiety or depression.

Conclusions: MS patients with anxiety and depression demonstrated higher fatigue and global impact disease scores. Although the data do not demonstrate a causal relationship, the treatment of the comorbidities is relevant to determine the improvement of the most impaired functions.