The Reciprocal Relationship between Social Relationships and Depression Among Older Adults: A Longitudinal Study Differentiating By Age Groups

Background and Purpose:

The importance of 'aging in place' is becoming increasingly prominent due to the serious issue of population aging in most developed countries. These issues are significant in Korea as it is experiencing rapid aging, and older adults are facing severe mental health challenges due to disrupted social relationships. Despite its severity, depression tends to be overlooked as a natural phenomenon associated with increasing age, and social relationships have been considered to have an unidirectional effect on depression. However, the relationship between depression and social relationships can be bidirectional. Previous studies have mainly dealt with a one-sided relationship between social relationships and depression, and there is a lack of research verifying mutual causality between the two variables. Therefore, this study longitudinally examines the correlation between social relationships and depression, assessing group differences.

Methods:

This study used data from the Korea Welfare Panel Study from 2019 to 2022, and 2,973 middle-aged and older households were set as the final analysis target. The study conducted autoregressive cross-lagged modeling to determine the relationship between social relationships and depression and a multi-group analysis to examine differences between groups by dividing the group into those aged 55-64 (N=1,337) and those aged 65 or older (N=1,636).

Results:

Correlation analysis between depression and social relationship variables confirmed statistical significance (p<.001). Regarding the longitudinal causal relationship between social relationships and depression, social relationships in the previous year (t-1) had a continuous influence on social relationships in the following year (t), and the magnitude of the influence was confirmed to be high (β=.751 → .732 → .745). Similarly, depression in the previous year significantly impacted depression in the following year, with a high magnitude of influence (β=.329 → .340 → .333). The cross-lagged coefficient, explaining social relationships in the previous year and social relationships in the next year, was significant at all time points (p<.001). The cross-lagged effect of social relationships on depression was found to be greater than the reverse. The cross-lagged effect of depression on social relationships differed by age group. For those aged 55 to 64, depression did not predict social relationships in the following year, but for those aged 65 or older, depression had a statistically significant impact on social relationships in the following year (p<.001).

Conclusions and Implications:

The cross-lagged effect of depression on social relationships showed different patterns by age group. These results suggest that both directions of influence should be considered in interventions in social work practice and that interventions targeting depression in older adults should be tailored to take age-specific epidemiology into account. Specifically, for older adults aged 55 to 64 years, a focus on strengthening social relationships may be particularly effective, while for older adults aged 65 years and older, the bidirectional relationship between social relationships and depression should be addressed. However, this study divided older adults into two broad age groups, which may oversimplify age-related differences in the relationship between social relationships and depression, so future studies need to perform more detailed analyses by further disaggregating age.