Abstract
Background: Cognitive decline is a chronic condition which is characterized by a loss of the ability to remember, learn, and pay attention to complex tasks. Many older people are now suffering from cognitive decline, which decreases life quality and leads to disability. This study aimed to identify the risk and protective factors for cognitive decline of the older people from daily life and establish a predictive model using logistic regression.
Methods: We investigated 3,790 older people with health examination and questionnaires which included information associated with physical condition, lifestyle factors, and cognitive status. Single-factor comparison, principal component analysis with a Manova-Wilk test, and logistic regression were performed to filter the risk and protective factors regarding cognitive decline of older individuals.
Results: We found a significant separation along the coordinate axis between people with normal and declined cognition by principal component analysis, as confirmed by the Manover-Wilk test. Single-factor comparison and logistic regression demonstrated significant difference in gender, age, hypertension level, height, dietary habit, physical-exercise duration, physical-exercise history, and smoking history between the two groups. We also observed significant differences in height, physical exercise duration, physical-exercise years, and smoking years between the male and female of the participants. ROCs of the predictive model by logistic regression were plotted, with AUC values of 0.683 and 0.682 respectively for the training and testing sets.
Conclusion: The protective factors of cognitive decline for older people were male gender, height, keeping exercising, and nicotine stimulation, and the risk factors included age, female gender, vegetarianism, hypertension, and over-exercise. Except for the genetic factor, differences in lifestyle, such as smoking and exercise habits, may contribute to the observed differences in cognitive function between genders.