Objectives: The neuropsychiatric sequelae of multiple sclerosis (MS) are important predictors of morbidity and mortality. The authors examined how symptoms of depression, anxiety, fatigue, subjective cognitive impairment, and objective cognitive dysfunction varied with disease duration. They also explored changes in the use of disease-modifying therapies, psychotropic medications, and psychotherapies in relation to disease duration.
Methods: A retrospective sample of 464 people with MS was stratified into three groups based on disease duration: <5 years (N=129), 5-10 years (N=101), and >10 years (N=234). Symptoms of depression and anxiety were recorded with the Hospital Anxiety and Depression Scale (HADS); fatigue, with the five-item version of the Modified Fatigue Impact Scale (MFIS-5); subjective cognitive impairment, with the five-item version of the Perceived Deficits Questionnaire (PDQ-5); and cognition, with the Minimal Assessment of Cognitive Function in MS (MACFIMS).
Results: There were between-group differences in anxiety symptoms (p<0.01) and degree of cognitive impairment (p=0.03), but there were no differences in depressive symptoms, fatigue, or subjective cognitive difficulties. Anxiety was higher during the first 5 years after diagnosis, and cognitive dysfunction was higher when assessed more than 10 years after diagnosis. With longer disease duration, a greater proportion of participants received psychotropic medications (p<0.01), and lower proportions received disease-modifying therapies (p<0.01) or psychotherapies (p<0.01).
Conclusions: Findings indicated that rates of some neuropsychiatric symptoms, such as anxiety and cognitive dysfunction, may shift with disease duration, whereas other symptoms, such as fatigue and depression, may not. These findings highlight the importance of closely monitoring the mental state of people with MS over time.
Keywords: Anxiety; Cognitive dysfunction; Depression; Disease duration; Fatigue; Multiple sclerosis.