Longitudinal assessment of deficit unawareness in Alzheimer's disease.
Longitudinal progression of impaired deficit awareness across varied functional domains was evaluated in 28 patients diagnosed with probable Alzheimer's disease (AD). Unawareness, as measured by patient-caregiver rating discordance, was first assessed in reference to patient memory, health status, self-care skills, anxiety, depression and irritability. The identical protocol was then repeated an average of 16.4 months later. Results indicated that, compared with caregiver ratings, patients tended to underestimate their deficits across functional domains. Patient-caregiver rating discrepancies were most pronounced in judgment of memory and self-care decline, indicating domain-specific differences in degree of unawareness. However, patient-caregiver rating discrepancies increased on most measures from time 1 to time 2 with no differences in the magnitude of these increases, suggesting a nonspecific longitudinal progression of unawareness. Although unawareness of deficits increased with time, longitudinal change in unawareness was not related to other disease and demographic variables such as age, education, age at onset, or duration of illness.