Department of Social and Behavioral Sciences, Harvard School of Public Health, , Boston, Massachusetts, USA.
J Epidemiol Community Health. 2014 Feb;68(2):110-5. doi: 10.1136/jech-2013-203093. Epub 2013 Sep 24.
Although cross-sectional and ecological studies have shown that higher area-level income inequality is related to increased risk for depression, few longitudinal studies have been conducted. This investigation examines the relationship between state-level income inequality and major depression among adults participating in a population-based, representative longitudinal study.
We used data from the National Epidemiologic Survey on Alcohol and Related Conditions (n=34 653). Respondents completed structured diagnostic interviews at baseline (2001-2002) and follow-up (2004-2005). Weighted multilevel modelling was used to determine if U.S. state-level income inequality (measured by the Gini coefficient) was a significant predictor of depression at baseline and at follow-up, while controlling for individual-level and state-level covariates. We also repeated the longitudinal analyses, excluding those who had a history of depression or at baseline, in order to test whether income inequality was related to incident depression.
State-level inequality was associated with increased incidence of depression among women but not men. In comparison to women residing in states belonging to the lowest quintile of income inequality, women were at increased risk for depression in the second (OR=1.18, 95% CI 0.86 to 1.62), third (OR=1.22, 95% CI 0.91 to 1.62), fourth (OR=1.37, 95% CI 1.03 to 1.82) and fifth (OR=1.50, 95% CI 1.14 to 1.96) quintiles at follow-up (p<0.05 for the linear trend).
Living in a state with higher income inequality increases the risk for the development of depression among women.
尽管横断面和生态学研究表明，地区收入不平等程度越高，患抑郁症的风险就越大，但很少有纵向研究。本研究调查了州级收入不平等与参与基于人群的代表性纵向研究的成年人中重度抑郁症之间的关系。
我们使用了来自全国酒精和相关条件流行病学调查的数据（n=34653）。受访者在基线（2001-2002 年）和随访（2004-2005 年）时完成了结构化的诊断访谈。使用加权多层次模型来确定美国州级收入不平等（用基尼系数衡量）是否是基线和随访时抑郁的重要预测因素，同时控制了个体水平和州级水平的协变量。我们还重复了纵向分析，排除了有抑郁病史或基线时患有抑郁的人，以检验收入不平等是否与新发抑郁有关。
州级不平等与女性而非男性的抑郁发生率增加有关。与居住在收入不平等程度最低五分位数的州的女性相比，在随访时，女性在第二（OR=1.18，95%CI 0.86 至 1.62）、第三（OR=1.22，95%CI 0.91 至 1.62）、第四（OR=1.37，95%CI 1.03 至 1.82）和第五（OR=1.50，95%CI 1.14 至 1.96）五分位数的抑郁风险更高（线性趋势的 p<0.05）。
生活在收入不平等程度较高的州会增加女性患抑郁症的风险。
