Multiple Sclerosis and Cognitive Impairment

Abstract

A 60-year-old woman with a history of multiple sclerosis was evaluated for cognitive concerns. At age 30 years she had an episode of optic neuritis, followed by an episode of bilateral lower extremity numbness at age 35 years. In the following years, she had at least 6 further multiple sclerosis relapses, the last one approximately 3 years before the current presentation. She was initially treated with interferon, but she did not tolerate it. She had been taking glatiramer acetate for the past 3 years. She had noticed progressive deterioration of her gait for the past 3 years, having to use a cane on occasions. Magnetic resonance imaging of the brain showed multiple demyelinating lesions), and magnetic resonance imaging of the cervical spine showed 1 small demyelinating lesion at C6. Vitamin B12 level and thyroid function were normal. Comprehensive neuropsychological testing showed multidomain cognitive impairment, mainly impairment of speed of information processing, spatial discrimination skills, and attention/concentration. The patient’s multiple sclerosis phenotype was consistent with secondary progressive multiple sclerosis. Her cognitive impairment profile, mainly affecting information processing speed and disinhibition suggestive of frontal dysfunction, was consistent with multiple sclerosis. The patient began a cognitive rehabilitation program, and learning and memory aids were recommended. Lifestyle changes were also recommended, including weight loss and physical exercise. She was given recommendations for sleep hygiene and began taking gabapentin for neuropathic pain and restless legs. Cognitive impairment is common in patients with multiple sclerosis. Slowed cognitive processing speed and episodic memory decline are the most common cognitive deficits in MS, with additional difficulties in executive function, verbal fluency, and visuospatial analysis.