Hua-fei Li,1,* Jie Chen,2,* Yi-feng Ge,1 Shu-jia Liu,3 Li-jing Zhou,2 Guo-gang Dong2 

1Department of Reproductive Medicine, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu Province, 210000, People’s Republic of China; 2The Second Outpatient Department, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu Province, 210000, People’s Republic of China; 3School of Medical Administration, Nanjing Medical University, Nanjing, Jiangsu Province, 210000, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Guo-gang Dong, The Second Outpatient Department, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, No. 1, Xiaoying North Road, Xuanwu District, Nanjing, Jiangsu Province, 210000, People’s Republic of China, Tel +8615952001000, Email guogangdongddd@126.com Li-jing Zhou, The Second Outpatient Department, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, No. 1, Xiaoying North Road, Xuanwu District, Nanjing, Jiangsu Province, 210000, People’s Republic of China, Tel +8618045268999, Email lijingzhouzljll@126.com

Objective: The objective of this study is to investigate and compare the mental health status of personnel stationed at high- and low-altitude bases to provide a reference for future targeted mental health education and support initiatives.
Methods: A total of 1,244 personnel posted in both high- and low-altitude bases were randomly selected using a cluster sampling method. Basic details were collected using a demographic information questionnaire, and their mental health status was assessed using the Symptom Checklist-90 (SCL-90). Statistical analyses included t-tests and Mann–Whitney U-tests. Principal component analysis (PCA) based on a Random Forest algorithm was employed to evaluate psychological symptom patterns.
Results: The mental health status of personnel included in this study surpassed the national average for China, with personnel stationed at high-altitude bases reporting better overall mental health than those stationed at low-altitude bases. Among personnel with similar educational backgrounds, those stationed at low-altitude bases had higher levels of interpersonal sensitivity, phobic anxiety, and depressive symptoms than their counterparts stationed at high-altitude bases. Over time in service, the primary psychological issues they experienced shifted from anxiety and paranoia to interpersonal sensitivity, obsessive compulsive disorder, and depression. Additionally, those stationed at low bases with lower incomes reported higher levels of phobic symptoms compared to personnel stationed at high-altitude bases.
Conclusion: In this study, we found that the psychological status of personnel stationed at high- and low-altitude bases was primarily influenced by factors such as income, level of education, years of military service, and geographical . Measures such as enhancing income and welfare benefits as appropriate, improving education levels by advancing educational opportunities, and providing more mental health education and training may effectively reduce psychological stress and contribute to building a resilient and psychologically healthy military force.

Keywords: altitude, comparative analysis, mental health, personnel, symptom checklist-90, SCL-90