Core depressive symptoms in middle-aged and older adults in the USA, England, China, and Mexico: Evidence from network analysis.

BACKGROUND: Depressive symptoms in middle-aged and older adults are a worrying issue. Identifying core depressive symptoms in this population through network analysis is critical for the prevention, diagnosis, and treatment of depressive symptoms.

METHODS: Our sample included 24,401 participants, of which 9072 were from the Health and Retirement Study (2012-2020), 2083 from the English Longitudinal Study of Ageing (2012-2020), 6153 from the China Health and Retirement Longitudinal Study (2011-2020), and 7093 from the Mexican Health and Aging Study (2012-2021). Expected influence (EI) in cross-sectional networks and "in" expected influence (In-EI) and "out" expected influence (Out-EI) in cross-lagged panel networks were used to identify core depressive symptoms across different countries and time points/periods.

RESULTS: The nodes with the highest EI/In-EI values remained relatively stable, all being "felt depressed/sad" across countries. In contrast, the nodes with the highest Out-EI values exhibited greater instability across countries. Yet, when ranking the mean order of Out-EI values among nodes, "anhedonia" emerged as the highest in China, whereas "felt lonely" topped the list in other countries.

CONCLUSIONS: For middle-aged and older populations in the USA, England, China, and Mexico, sad/depressed feelings should be recognized as a stable and timeless core symptom in the prevention, diagnosis, and treatment of depressive symptoms. Additionally, to reduce or prevent their subsequent depressive symptoms, it is also necessary to consider addressing feelings of loneliness in countries such as Mexico, the USA, and England, while for China, a key focus should be on anhedonia.