Anosognosia in Alzheimer disease

This study evaluated Alzheimer disease (AD) patients' awareness of impairment in several domains, including cognitive, psychiatric, and behavioral functioning. Ratings made by 13 patients with moderate to moderately severe probable AD were compared with ratings made by their relatives using the Cognitive Behavior Rating Scales (Williams et al., 1985; Williams, 1987). Unawareness was defined as the discrepancy between informant and patient ratings. Informants consistently rated patients' impairment as more severe than the patients rated themselves. However, the discrepancy between the ratings was statistically significant only for Language Disorder, Higher Cognitive Deficits, Memory Disorder, Dementia, and Apraxia, and not for Agitation, Need for Routine, Depression, and Disorientation scales. Unawareness was not related to severity of memory impairment, as measured by the Rivermead Behavioural Memory Test (Wilson et al., 1985). The results of this small, preliminary study of relatively severely impaired AD patients suggest that awareness of psychiatric and behavioral problems may be relatively preserved compared to awareness of cognitive problems. These findings should be replicated with a larger sample with a broader range of severity.