The mediating effect of perceived stress on the relationship between big five personality traits and suboptimal health status: A national cross-sectional survey in China
Authors: Guan Qihua , Dong Hualei , Zhang Zhihui , Guo Zheng , Lin Zi , Niu Hui , Wu Yibo , Hou Haifeng 
Published: September 2023

Abstract
Background
Psychological factor plays a crucial role in the development of suboptimal health status (SHS), however the mechanism behind the complex relationship between big five personality traits and SHS is unclear. Identification of the individuals with specific personality trait that is susceptible to SHS will contribute to improving quality of life and decreasing the burdens of chronic diseases in the framework of predictive, preventive and personalized medicine (PPPM/3PM). This study aimed to investigate the relationship between personality traits and SHS, and whether perceived stress plays a mediating effect in the development of SHS.
Method
A nationwide cross-sectional survey based on multistage random sampling was conducted in 148 cities of China from June 20 to August 31, 2022. The personality traits, perceived stress and SHS were measured with Big Five Inventory-10 (BFI-10), Perceived Stress Scale-4 items (PSS-4), and Short-Form Suboptimal Health Status Questionnaire (SHSQ-SF), respectively. Pearson’s correlation analysis was employed to examine the associations between personality traits, perceived stress, and SHS. Structural equation model (SEM) was applied to explore the mediating role played by perceived stress in the relationship between personality traits and SHS.
Result
A total of 22,897 participants were enrolled in this study, among whom the prevalence of SHS was 52.88%. SHS was negatively correlated with three dimensions of personality traits (i.e., extraversion, agreeableness, and conscientiousness), and positively correlated with neuroticism. Meanwhile, stress was negatively correlated with extraversion, agreeableness, conscientiousness, and openness, whereas in positive association with neuroticism. The SEM analysis showed that, adjusted for the covariables (i.e., gender, age, BMI, educational level, current residence, marital status, and occupational status), agreeableness (β = -0.049, P < 0.001) and conscientiousness (β = -0.103, P < 0.001) caused a lower prevalence of SHS, while neuroticism (β = 0.130, P < 0.001) and openness (β = 0.026, P < 0.001) induced a higher prevalence of SHS. Perceived stress played a partial mediating role in the relationship between personality traits and SHS, contributing to 41.3%, 35.9% and 32.5% of the total effects of agreeableness, conscientiousness and neuroticism on SHS, respectively. Moreover, the mediating effect of perceived stress was significant even though extraversion had no direct effect on SHS.
Conclusion
This study revealed a high prevalence of SHS in Chinese residents. Personality traits of individuals have significant effects on the occurrence of SHS, which can be mediated by their perceived stress. From a PPPM/3PM perspective, early screening and targeted intervention for persons with neuroticism trait, as well as stress alleviation, might contribute to health improvement and chronic diseases prevention.