Subjective Memory Complaints in young and older healthy people: Importance of anxiety, positivity, and cortisol indexes

Subjective memory complaints (SMCs) are common among older people, but they also appear in young adults. Hence, SMCs deserve attention in the different periods of life. SMCs have been related to hypothalamic-pituitary-adrenal (HPA) axis functioning, and negative traits also seem to be related to SMCs, whereas protective traits have been hardly studied. We aimed to study the predictive value of anxiety and positivity in SMCs and explore whether they moderated the relationship between the HPA axis and SMCs in different age periods. Trait anxiety, positivity, and cortisol were measured in 75 healthy young adults (aged 18 to 35 years old; Study 1) and 73 older adults (aged 55 to 75 years old; Study 2). In both studies, anxiety was related to SMCs in the entire sample, whereas positivity was only related to SMCs in younger subjects and older women. Differences were found between the young and older groups in the relationship between the HPA axis and SMCs, given that it was moderated by psychological traits in younger adults and only by age in older adults (when we compared those aged 55 to 64 vs 65 to 75). These findings emphasize the different nature of SMCs in different age periods of the lifespan.