Faculty Bibliography

Prior studies have reported an association between visual evoked potentials (VEPs) and cognitive performance in people with multiple sclerosis (PwMS), but the specific mechanisms that account for this relationship remain unclear. We examined the relationship between VEP latency and cognitive performance in a large sample of PwMS, hypothesizing that VEP latency indexes not only visual system functioning but also general neural efficiency. Standardized performance index scores were obtained for the domains of memory, executive function, visual-spatial processing, verbal function, attention, information processing speed, and motor skills, as well as global cognitive performance (NeuroTrax battery). VEP P100 component latency was obtained using a standard checkerboard pattern-reversal paradigm. Prolonged VEP latency was significantly associated with poorer performance in multiple cognitive domains, and with the number of cognitive domains in which performance was ≥ 1 SD below the normative mean. Relationships between VEP latency and cognitive performance were significant for information processing speed, executive function, attention, motor skills, and global cognitive performance after controlling for disease duration, visual acuity, and inter-ocular latency differences. This study provides evidence that VEP latency delays index general neural inefficiency that is associated with cognitive disturbances in PwMS.

Multiple sclerosis (MS) is a chronic inflammatory and demyelinating disease of the central nervous system. The disease affects more women than men and often is diagnosed during a woman's childbearing years. Typical clinical presentations of the disease are extensive and variable, with symptoms that include dysregulated mood, fatigue, vision problems, weakness, tremor, imbalance, abnormal sensations, bladder dysfunction, and heat sensitivity. If a woman aged 15-50 years experiences these neurologic symptoms in isolation or combination, and the symptoms are not explained by other underlying medical conditions, MS should be suspected. Multiple sclerosis can be divided into four clinical subtypes: 1) relapsing-remitting MS, 2) secondary progressive MS, 3) primary progressive MS, and 4) clinically isolated syndrome. Relapsing-remitting MS at the time of onset is the most common form and accounts for approximately 80% of all cases of MS. Relapsing-remitting MS does not affect life expectancy. However, because of the neurodegenerative and progressive course of the disease, patients accumulate physical and cognitive disabilities over time that result in impaired ability to work, increased financial burden, and slightly increased mortality. A variety of possible risk and prognostic indicators have been identified that may predict the course of disease, particularly the extent of relapses and disability. Multiple sclerosis currently is incurable, but many disease-modifying therapies are available that can reduce the frequency of clinically evident exacerbations and accumulation of disease burden as defined by the number of lesions identified on magnetic resonance imaging. The choice of disease-modifying therapies, contraception use, and treatment of symptoms should be individualized based on age at onset and disease activity and, during pregnancy, the gestational age. Proactive management of MS across the woman's life cycle reduces morbidity, improves maternal and fetal health during pregnancy and the postpartum period, and increases quality-of life-measures for patients and their families.