The factors associated with subjective cognitive decline and cognitive function among older adults

To explore the risk factors for subjective cognitive decline and cognitive function among older adults in South Korea.

This study employed a descriptive cross-sectional design.

A convenience sample of 182 patients was recruited from a senior welfare center in Seoul. The mean age of the participants was 78.4 years (SD 5.91). Among them, 64.3% were women. The data were collected by a trained research assistant using structured questionnaires from September 2016-February 2017. Demographic characteristics, comorbidities, depression, physical and cognitive activity levels, instrumental activities of daily living, subjective cognitive decline, and cognitive function were assessed. Student's t tests, chi-square tests, and hierarchical multiple regression analyses were used for statistical analyses.

The findings revealed that 37.4% of the participants were not cognitively intact. Depression, perceived health status, and cognitive function were significantly associated with subjective cognitive decline (F = 7.10, p < .001, adjusted R²  = 25.3). Age, educational level, perceived health status, and subjective cognitive decline were significantly related to cognitive function (F = 20.98, p < .001, adjusted R²  = 47.0). After controlling for these variables, cognitive activity was significantly and independently related to cognitive function.

The results suggest that for the maintenance of cognitive function, cognitive activity should be encouraged. In addition, older adults who complain of subjective cognitive decline and have risk factors such as depression need therapeutic interventions to prevent actual decrease of cognitive function.

The present findings advance prior knowledge by considering variables such as physical and cognitive activity levels to provide novel evidence that can be used to develop interventions for community-dwelling older adults. Thus, to be effective, nursing interventions must seek to improve cognitive function through intellectual stimulation.