Stressful events and severity of memory complaints in cognitively normal adults aged from 25 to 85 years

Abstract

The relationships between subjective cognitive difficulties and stressful events (SE) have rarely been examined. Broadbent et al. (1982) suggested that such difficulties disclose a high sensitivity to stress, independently of depression and personality. To explore the relationships between the severity of memory complaints and SE occurred during the previous year. 260 cognitively normal subjects, aged from 25 to 85 years were examined in a Memory clinic through one year. The severity of memory complaints was globally assessed by asking the participants to qualify the intensity of their subjective difficulties as major or minor, and quantitatively, by using a 8-item subjective memory scale. SE were assessed by asking the subjects whether they experienced one or more events that had negative effects on their physic or mental well-being in the domains of health, family, social environment and financial position during the last 12 months. Affective status was assessed by the Zung's depression (ZD) and anxiety (ZA) scales, and by a Wellbeing questionnaire, QBE. Cognition was assessed using a semi-computerized battery exploring memory and several cognitive abilities. SE were reported in 156 subjects (60%). No differences were found between subjects with or without SE according to age, genre, familial status and activity, as well as cognitive performance. Subjects with SE reported more severe complaints and higher scores on ZD and ZA scales, and lower scores on the QBE. Severity of memory complaints was mainly correlated to QBE in subjects with SE and to ZA scale in subjects without. Subjects with age< 50 years reported more SE than subjects aged≥50 years. No difference was found between the two age groups according to the type of SE in the domain of health, family, and finances, but higher SE were reported in younger subjects in the domain of social environment. The main correlates of the severity of memory complaints were depression in younger subjects with or without SE, and anxiety in absence of SE and QBE in presence of SE in older subjects. However, the affective scores explained only a weak part of the variance of the severity of memory complaints. SE do not seem to play a direct role in the severity of memory complaints, but they increase the affective disturbances. We suggest that anxiety and various factors such as decrease in self-esteem and modification of self-identity result in a psychological vulnerability which contribute to memory complaints.