Better Sleep, Better Minds: Sleep as a Key to Cognitive Performance and Quality of Life in Aging

Cognitive decline can significantly affect the quality of life of healthy older adults. There is an age-associated cognitive decline, but there is also evidence that sleep quality is also affected by the aging process. The primary aim of this study is to evaluate whether sleep quality moderated the relationship between cognitive performance and quality of life on a sample of healthy older adults, as well as to evaluate differences between men and women in cognitive performance, sleep quality and perceived quality of life. A final sample of 50 participants was included with a mean age of 66.57 years (71.43% women). Participants completed a battery of questionnaires, including the Fototest (cognitive performance), the Pittsburgh Sleep Quality Index (PSQI) (sleep quality), and European Quality of Life 5 Dimensions (EuroQoL-5D) (perceived quality of life). A correlation analysis was performed for Fototest, EuroQoL-5D, and PSQI scores and the three variables were significantly related in the global sample. Women maintained a similar pattern of relationships between the main variables, whereas none of the correlations reached statistical significance for men. Also, a multiple linear regression analysis was performed and both, cognitive performance and sleep quality, significantly predicted perceived quality of life. Furthermore, a moderation model analysis was conducted explaining approximately 42.2% of the variance in quality of life (R2 = 0.42), F(4, 37) = 6.76, p < .001. Specifically, results showed that sleep quality not only directly influences perceived quality of life but also moderates the relationship between cognitive performance and quality of life. In conclusion, it would be interesting to promote further research on the weight that sleep quality may have when implementing a cognitive intervention program in a sample of older adults, as well as to have a forecast of the impact that such intervention will have on the sample, considering the quality of sleep of the individuals.