Cognitive problems like confusion or forgetfulness can cause great concern for older adults and their families, who are often concerned that these complaints may be early signs of dementia. Although these cognitive complaints may be caused by neurological impairments, they are often the result of other psychological distress such as anxiety or depression. When clinical attention is sought for these cognitive complaints, clinicians will typically consult with other informants (such as the patient’s family) as well as the patient, for observations that will help determine the underlying cause of the complaints. A study in Alzheimer’s & Dementia examines whether self- or informant-based cognitive complaints are more useful in determining whether cognitive complaints are symptoms of dementia, or of psychological distress.
The study was based on a longitudinal sample of 447 individuals between the ages of 45 and 79. Participants had a family history of dementia, but did not have any diagnosis of cognitive decline at the beginning of the study. At the beginning of the study, participants were given a neurological examination, a variety of cognitive and mood disorder assessments, and a medical history screening. Participants were then administered a battery of neuropsychological tests every two years, which included self- and informant-based questionnaires about potential cognitive and functional impairments on the part of the participants, and questions about symptoms of depression or anxiety. (Most informants were spouses of the participants.)
Around 31 percent of participants self-reported some cognitive complaints during the study, and 26.2 percent of participants had an informant-derived complaint. During this period, only 20 of the participants (or less than 5 percent) developed a clinically diagnosed cognitive impairment, though many participants did experience some clinically non-significant decrease in cognitive test scores. Many self- and informant-observed cognitive symptoms were related to other psychological explanations rather than neurologically driven cognitive decline.
Overall, within this sample, self-reported cognitive symptoms were as clinically useful as informant-based complaints, and both had a closer association with psychological distress than with clinically diagnosable cognitive impairment. In about half of the 20 cases that eventually led to a diagnosis of cognitive decline, participants identified cognitive symptoms before other informants did. Self reports and informant-observed reports happened together in the other half of cases, while there was only one case in which informants observed cognitive decline symptoms first.