Background Most studies exploring the association between social isolation and depression tend to focus on Western countries. The primary aim of this longitudinal study was to examine the association between social isolation and depression onset among middle-aged and older adults in China.
Methods Data on 6,817 participants (mean age = 57.91, SD = 8.77; men, 52.1%) from the first and fourth waves of the China Health and Retirement Longitudinal Study (CHARLS) were analyzed. Binary logistic regressions were used to evaluate the association between social isolation and depression onset. The moderating effects of socioeconomic status (education) and gender differences were also examined.
Results Social isolation was significantly associated with depression onset (OR = 1.24, 95% CI = 1.10–1.41). Compared to men with lower education (OR = 0.97, 95% CI = 0.77–1.23), those with higher education (OR = 1.91, 95% CI = 1.40–2.60) exhibited a greater association between social isolation and depression onset. Moderating effect of education was not found for women.
Limitations Depression were self-reported, which might be less reliable than clinical interview.
Conclusions Our results suggested that high level of social isolation was significantly associated with a higher incidence of depression among middle-aged and older adults in China. Education played a moderating role in this association for men rather than women.