Participant-Informant Relationships Affect Quality of Life Ratings in Incipient and Clinical Alzheimer Disease.
OBJECTIVE
Clinical trials in incipient and clinical Alzheimer disease (AD) often include informant-reported outcomes. Whereas informant reports in AD dementia may be modulated by the nature of participant-informant relationships, whether informant type affects reporting at earlier disease stages is less certain. We sought to determine the effects of participant-informant relationships on informant assessments of quality of life (QOL), functional abilities, and behavioral symptoms in individuals with normal cognition (NC), mild cognitive impairment (MCI), and mild-to-moderate AD dementia.


METHODS
Cross-sectional.


METHODS
Easton Center for Alzheimer Disease Research at the University of California, Los Angeles.


METHODS
A total of 399 individuals who met criteria for NC (N = 100), MCI [amnestic (N = 125) and nonamnestic (N = 61)], and AD (N = 113). Participants were subdivided into groups based on informant-participant relationships (spouse versus other).


METHODS
We examined informant effects on the Quality of Life-Alzheimer's Disease (QOL-AD) scale, the Functional Activities Questionnaire (FAQ), and the Neuropsychiatric Inventory (NPI).


RESULTS
After adjustments for demographic and cognitive factors, spouse informants reported higher participant QOL in the amnestic MCI and AD groups than did other informants. No informant effects were seen on QOL-AD ratings in the nonamnestic MCI or NC groups or on the FAQ or NPI in the MCI and AD groups.


CONCLUSIONS
Participant-informant relationships may modulate informant responses on subjective measures such as the QOL-AD in both incipient and clinical AD. Clinical trials that use informant measures may need to address these effects.
Keck School of Medicine, University of Southern California, Los Angeles, CA.
Amy
A
Lin
Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA.
Jenny
J
Brook
Department of Psychiatry and Human Behavior, Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA.
Joshua D
JD
Grill
Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA; Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA. Electronic address: eteng@mednet.ucla.edu.
Edmond
E
Teng
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000523:psychology*; D000647:Amnesia / Q000523:psychology*; D060825:Cognitive Dysfunction / Q000523:psychology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007398:Interpersonal Relations; D008297:Male; D008875:Middle Aged; D011788:Quality of Life / Q000523:psychology*; D018454:Spouses / Q000523:psychology*
Alzheimer disease; Informant; mild cognitive impairment; quality of life; study partner