Awareness of cognitive deficits in older adults with epilepsy and mild cognitive impairment

A significant portion of individuals with mild cognitive impairment (MCI) experience limited awareness of cognitive deficits. Although older adults with epilepsy have comparable cognitive deficits to individuals with MCI, little is known about awareness of cognitive deficit in epilepsy. This study compared deficit awareness in epilepsy and MCI and examined its relationship with neuropsychological performance.

Sixty-two older adults (31 epilepsy, 31 MCI) completed neuropsychological testing and the Cognitive Difficulties Scale (CDS), a self-report measure of everyday cognitive skills. Informants completed the CDS only. Cognitive domain scores were created. CDS composite scores were created by summing attention-concentration and language and delayed memory factors. Awareness was defined as the difference between patient and informant CDS scores, with limited awareness defined as greater informant complaints.

Neuropsychological performance was similar between groups for all domains except that MCI participants had worse delayed memory, t(60) = 2.49, p < .05. CDS scores were similar between patient groups (p > .05). Epilepsy informant CDS scores were related to poorer immediate memory (r = -.41, p = .02). MCI informant CDS scores were related to worse delayed memory (r = -.41, p = .02). Limited awareness was found in 29.0% of epilepsy and 61.3% of MCI participants. Awareness was not related to cognition in epilepsy but was related to worse delayed memory (r = -.41, p = .02) for MCI participants.

Older adults with epilepsy and MCI had similar cognitive deficits with the exception of greater impairment in delayed memory for MCI patients. There was less awareness of deficit in the MCI group, suggesting that delayed memory may be a critical factor for deficit awareness. Results argue against executive dysfunction as a major contributor to deficit awareness.