Do memory complaints indicate the presence of cognitive impairment? – Results of a field study

Background: In the context of suspected cognitive disorders, the validity of memory complaints is subject to considerable debate. This investigation documents the prevalence of memory complaints and assesses the validity of memory complaints for detecting cognitive impairment. Methods: The sample comprises 349 randomly selected non-institutionalized individuals, aged 75 and over living in the city of Leipzig. Twenty individuals who suffer from moderate and severe dementia according to DSM-III-R were excluded. Memory complaints were measured by means of a single item question. The Mini-Mental State Examination (MMSE) and a wider range of cognitive tests which constitute the short neuropsychological battery of the SIDAM (Structured Interview for the Diagnosis of dementia of Alzheimer type, Multi-infarct dementia and dementias of other etiology according to ICD-10 and DSM-III-R) were used to test cognitive performance. Results: One in three individuals aged 75 and over complained about memory deficits. The MMSE is not significantly related to memory complaints, whereas poorer performance on 2 out of 8 tests regarding specific areas of cognitive function (immediate recall, short-term memory) were found to be significantly associated with memory complaints. Despite these statistically significant associations, it is shown that memory complaints do not have diagnostic validity in detecting cognitive impairment on the individual level. Conclusion: Memory self-assessment should not be used as a substitute measure of cognitive performance. Initiation of further diagnostic and therapeutic steps should be based on cognitive performance testing. Relaying solely on memory complaints would miss individuals in need and allocate resources to worried but cognitively healthy persons.