Prevalence and Predictors of “subjective Cognitive Complaints” in the Sydney Memory and Ageing Study

Objectives: To document the prevalence of self- and informant report of cognitive problems, usually referred to as "subjective cognitive complaints" (SCCs), in a community-dwelling sample of older adults and to examine the relationship between SCCs and objective impairment, mood, and personality measures.

Participants: Eight hundred twenty-seven nondemented community-dwelling adults aged 70-90 years.

Measurements: Participants were asked 24 SCC questions, including the Memory Complaint Questionnaire (MAC-Q), and completed neuropsychological testing in the domains of memory, language, executive function, visuospatial skills, and psychomotor speed. The Geriatric Depression Scale, Goldberg Anxiety Scale, and Neuroticism, Openness, and Conscientiousness from the NEO-Five Factor Inventory were used as measures of participants' psychological status. Informants completed 19 SCC questions, including a modified short Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE).

Results: Overall, 95.5% of participants or their informants endorsed at least one SCC. Although participants were more likely to endorse a memory complaint, informants seemed more accurate in endorsing a complaint when cognitive impairment was objectively present. SCC correlated with participants' scores on measures of depression, anxiety, neuroticism, and inversely with measures of openness and conscientiousness. Age, education, and sex had little impact on these effects. Regression analysis showed that psychological factors explained the number of complaints more than cognitive performance.

Conclusions: The usefulness of SCCs as a criterion for mild cognitive impairment is questioned because of their high prevalence and their relationship to psychological factors. This may be helpful for clinicians to bear in mind when presented with patients with cognitive complaints.