Anxiety, depression, and cognitive difficulties for individuals with Multiple Sclerosis

Abstract

Multiple Sclerosis (MS) is a chronic, neurologic disorder that may impact individuals physically, emotionally, and cognitively. There is limited research on anxiety for individuals with MS, and fewer studies examining the relationship of anxiety and cognitive difficulties for this population. Limited research has demonstrated anxiety is commonly comorbid with depression, and may occur with greater frequency. Cognitive dysfunction also appears frequently in MS, however the relationship of cognition and anxiety is not clearly understood. Information processing speed is one of the most commonly affected cognitive domains in MS. This study examined point-prevalence rates of anxiety, depression, and cognitive impairment; clinical correlates of anxiety; and effect of anxiety on cognition in MS. 110 MS patients completed measures assessing symptoms of mood (Hospital Anxiety and Depression Scale) and processing speed (Symbol Digit Modalities Test). Results indicated point-prevalence rates of clinically significant anxiety were 39.1% and 26.4% for depression. Frequency of processing speed deficits was 40.9%. Significant correlations were found: anxiety and depression (r = 0.60, p < 0.01) and anxiety and disease severity (r = 0.20, p < 0.01). Hierarchical multiple regression assessed ability of anxiety to predict processing speed, after adjusting for demographics and disease severity. Demographics (Step 1) explained 7% of variance in processing speed. After disease severity was entered (Step 2), variance explained was 18%. After entry of anxiety (Step 3), total variance explained by the model was 19%, F (5, 104) = 4.84, p < 0.05. Disease severity (beta = -0.36, p < 0.05) and gender (beta = 0.19, p < 0.05) were the only statistically significant control measures. Results of this study confirm that symptoms of anxiety, depression, and impaired processing speed were prevalent in this sample. Clinical correlates of anxiety found were similar to previous studies. Regression analyses found disease severity was the most robust predictor of cognitive dysfunction. Anxiety was not found to be an independent predictor of impaired processing speed. There is a need to further examine anxiety, depression, and cognition in MS to help screen individuals who may be at greater risk for anxiety or cognitive difficulties, and may benefit from early intervention.