SALT LAKE CITY—Depression may be underreported and untreated in patients with amnestic mild cognitive impairment (aMCI), because these patients lack insight into their moods, according to Po H. Lu, PsyD, and colleagues, who presented their findings at the 133rd Annual Meeting of the American Neurological Association.
Although anosognosia, or lack of awareness of impairment in motor, sensory, cognitive, and affective functioning, is common in patients with Alzheimer’s disease, it has not been studied sufficiently among patients with MCI. To investigate the possibility of a link between memory impairment and insight into mood, Dr. Lu’s group classified patients with aMCI (mean age, 78) into aware (n = 403) and unaware (n = 403) groups, based on the discrepancy score between their acknowledgment of memory deficits and clinician diagnosis.
Assessment tools included the questionnaire version of the Neuropsychiatric Inventory, the 15-item version of the Geriatric Depression Scale (GDS-15) to assess depressive symptoms, and a neuropsychologic test battery to determine the patient’s cognitive functioning. A cutoff score of 5 or greater on the GDS-15 determined the presence of at least mild depression. Use of chi-square tests enabled the investigators to examine differences in self-report and informant assessment between the groups.
Insight Into Impairment Leads to Awareness of Depression
The researchers found that more than 80% of unaware patients did not rate themselves as being depressed while informants rated them as such, compared with about 40% of aware patients. “Thus, subjects with poor insight into their memory abilities also show poor insight into their mood,” Dr. Lu told Neurology Reviews. Dr. Lu is Director of the Neuropsychology Laboratory at the Mary S. Easton Center for Alzheimer’s Disease Research and an Assistant Clinical Professor of Neurology at the David Geffen School of Medicine, at the University of California, Los Angeles.
According to Dr. Lu and colleagues, the current findings are consistent with those of previous studies showing that insight into cognitive impairment is associated with greater awareness of depression. “However, findings in the present study suggest that less depression in unaware aMCI may be due, in part, to a generalized lack of insight that affects their own perceptions about their mood,” the investigators stated.
The researchers suggested that, due to underreporting of depressive symptoms, some patients with aMCI may have undiagnosed and untreated depression.
“Informant report is critical for accurate diagnosis and treatment of psychiatric difficulties in aMCI patients,” Dr. Lu concluded.
—Laura Sassano