Cognitive impairment as a comorbidity of epilepsy in older adults: Analysis of global and domain-specific cognition

Objective: This study aimed to explore the association between epilepsy and cognitive impairment and to determine the factors associated with cognitive impairment in older people with epilepsy. Methods: People with epilepsy and controls aged >= 50 years were recruited and their global and domain-specific cognitive functions were evaluated by a comprehensive neuropsychological battery. Clinical characteristics were obtained from medical records. Analysis of covariance was used to examine the difference of cognition between two groups, after adjusting for age, gender, education years, hypertension, diabetes, and heart disease. A multiple linear regression model was used to explore the potential impact factors of cognitive functions among people with epilepsy. Results: This study recruited 90 people with epilepsy and 110 controls. The proportion of cognitive impairment among older adults with epilepsy was 62.2%, which was significantly higher than controls (25.5%, p < .001). People with epilepsy performed worse on global cognition (p < .001), especially in domains of memory (p < .001), executive function (p < .001), language (p < .001), and attention (p = .031). Among older adults with epilepsy, age was negatively correlated with the scores of memory (beta = -.303, p = .029), executive function (beta = -.354, p = .008), and attention (beta = -.558, p < .001). Females performed better on executive function (beta = -.350, p = .002) than males. Education years had a positive correlation with global cognition (beta =.314, p = .004). Number of antiseizure medications was also negatively correlated with scores of spatial construction function (beta = -.272, p = .019). Significance: Our results indicated that cognitive impairment was a major comorbidity of epilepsy. Number of antiseizure medications is suggested as a potential risk factor of impaired cognition in older people with epilepsy.