Abstract: Middle-aged people's depressive symptoms have negative impact on children and adolescents' mental health, family harmony, and the whole social mentality. Identifying the developmental trajectories of depressive symptoms can help to design effective prevention programs. Previous studies have reported 3 to 5 developmental trajectories of depressive symptoms among adolescents, early adults, and the elderly. However, whether this pattern can be generalized to Chinese middle adulthood needs to be studied further, based on the findings that the prevalence and influence factors associated with depressive symptoms are culture-dependent.
To date, studies on the developmental trajectories of depressive symptoms among middle adulthood are far from consistent. In addition, many cross-sectional studies have proved that depressive symptoms were also affected by gender, residence, the level of education, and other factors. Nonetheless, there are few longitudinal studies conducted to explore the risk factors for developmental trajectories. Therefore, the aim of the present longitudinal study is to examine developmental patterns of depressive symptoms in Chinese middle adulthood. In addition, we also examined whether the developmental patterns would differ by gender, residence, and the level of education.
Participants were 10654 middle adulthood (53.4% females; M_age = 43.2 years, SD = 4.4 years) from the China Family Panel Studies (CFPS) project conducted by China Social Science Survey Center of Peking University, recruited from 25 provinces in Mainland China. This study adopted longitudinal design at 3 times over the course of 6 years. The data were collected in 2012 for the first time, four years later for the second time, and two years later for the third time. Longitudinal data on depressive symptoms were measured by the short version of the Center for Epidemiologic Studies Depression Scale (CES-D), and the internal consistency reliability of the three measures was between .75 and .79.
The growth mixture modeling was used to explore the developmental trajectories, while logistic regression was used to examine the effects of gender, residence, and the level of education. The data were analyzed using SPSS18.0 and Mplus17.4, including descriptive analysis, correlation analysis, logistic regression, latent growth curve model, and growth mixture modeling. The results showed that: (1) The developmental trajectories of depressive symptoms among Chinese middle adulthood were identified with three different patterns: consistently low group (87%), low-sharp increasing group (5%), and moderate-slow decreasing group (8%). (2) Predictors of developmental trajectories with greater symptom burden included female gender, rural resident, and lower education, a larger percentage of the low-sharp increasing group, and moderate-slow decreasing group were females, rural residents and those with lower level of education.
The study made contributions to the knowledge on the development of middle adulthood's depressive symptoms in China. It was the first study to examine the developmental trajectories and risk factors of depressive symptoms among Chinese middle adulthood. Our findings have certain guiding significance for the improvement of middle adulthood's depressive symptoms.

Key words: middle adulthood, depressive symptoms, growth mixture modeling

摘要： 选取中国家庭追踪调查（CFPS）中的10654名成年中期被试,采用增长混合模型,探讨抑郁情绪变化轨迹的异质性及其相关因素。结果发现：成年中期抑郁情绪变化轨迹存在低抑郁-稳定组（87%）、中抑郁-下降组（8%）与低抑郁-陡升组（5%）三种类别,相对于低抑郁-稳定组,中抑郁-下降组和低抑郁-陡升组中女性、农村居民与受教育水平较低者所占比例更大。成年中期抑郁情绪的变化轨迹呈现异质性,并且女性、农村居民与受教育水平较低者存在更高的抑郁情绪发展风险。

关键词: 成年中期, 抑郁情绪, 增长混合模型