Division of Preventive Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
Department of Health Promotion Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
BMC Public Health. 2021 Nov 18;21(1):2120. doi: 10.1186/s12889-021-12168-8.
Income inequality has dramatically increased worldwide, and there is a need to re-evaluate the association between socio-economic status (SES) and depression. Relative contributions of household income and education to depression, as well as their interactions, have not been fully evaluated. This study aimed to examine the association between SES and depressive symptoms in Japanese adults, focusing on interactions between education and household income levels.
This cross-sectional study used data from baseline surveys of two cohort studies. Participants were 38,499 community-dwelling people aged 40-74 years who participated in baseline surveys of the Murakami cohort study (2011-2012) and Uonuma cohort study (2012-2015) conducted in Niigata Prefecture, Japan. Information regarding marital status, education level, household income, occupation, activities of daily living (ADL), and history of cancer, myocardial infarction, stroke, and diabetes was obtained using a self-administered questionnaire. Depressive symptoms were examined using the Center for Epidemiologic Studies Depression Scale (CES-D). Logistic regression analysis was used to obtain odds ratios (ORs). Covariates included age, sex, marital status, education, household income, occupation, ADL, and disease history.
Individuals with higher education levels had lower ORs (adjusted P for trend = 0.0007) for depressive symptoms, independently of household income level. The OR of the university-or-higher group was significantly lower than that of the junior high school group (adjusted OR = 0.79). Individuals with lower household income levels had higher ORs (adjusted P for trend< 0.0001) for depressive symptoms, independently of education level. The type of occupation was not associated with depressive symptoms. In subgroup analyses according to household income level, individuals with higher education levels had significantly lower ORs in the lowest- and lower-income groups (adjusted P for trend = 0.0275 and 0.0123, respectively), but not in higher- and highest-income groups (0.5214 and 0.0915, respectively).
Both education and household income levels are independently associated with the prevalence of depressive symptoms, with household income levels showing a more robust association with depressive symptoms than education levels. This suggests that a high household income level may offset the risk of depressive symptoms from having a low education level.
全球收入不平等状况显著加剧，因此需要重新评估社会经济地位（SES）与抑郁之间的关系。家庭收入和教育对抑郁的相对贡献，以及它们之间的相互作用，尚未得到充分评估。本研究旨在探讨日本成年人 SES 与抑郁症状之间的关系，重点关注教育和家庭收入水平之间的相互作用。
本横断面研究使用了两项队列研究基线调查的数据。参与者为 38499 名居住在社区、年龄在 40-74 岁之间的人群，他们参加了日本新潟县村上市队列研究（2011-2012 年）和鱼沼市队列研究（2012-2015 年）的基线调查。使用自填式问卷获取婚姻状况、教育程度、家庭收入、职业、日常生活活动（ADL）以及癌症、心肌梗死、中风和糖尿病病史等信息。使用流行病学研究中心抑郁量表（CES-D）评估抑郁症状。使用逻辑回归分析获得比值比（ORs）。协变量包括年龄、性别、婚姻状况、教育、家庭收入、职业、ADL 和疾病史。
与家庭收入水平无关，教育程度较高的个体抑郁症状的 OR 较低（趋势检验调整 P 值=0.0007）。大学及以上学历组的 OR 显著低于初中及以下学历组（调整 OR=0.79）。家庭收入水平较低的个体抑郁症状的 OR 较高（趋势检验调整 P 值<0.0001），与教育水平无关。职业类型与抑郁症状无关。根据家庭收入水平进行亚组分析，在收入最低和较低的两组中，教育程度较高的个体 OR 显著较低（趋势检验调整 P 值分别为 0.0275 和 0.0123），但在收入较高和最高的两组中则不然（OR 分别为 0.5214 和 0.0915）。
教育和家庭收入水平均与抑郁症状的发生率独立相关，家庭收入水平与抑郁症状的相关性强于教育水平。这表明高家庭收入水平可能会抵消低教育水平导致的抑郁症状风险。
