Background Perceived discrimination in health care settings can have adverse consequences on mental health in minority groups. However, the association between perceived discrimination and mental health is prone to unmeasured confounding. The study aims to quantitatively evaluate the influence of unmeasured confounding in this association, using g-estimation. Methods In a predominantly African American cohort, we applied g-estimation to estimate the association between perceived discrimination and mental health, adjusted and unadjusted for measured confounders. Mental health was measured using clinical diagnoses of anxiety, depression and bipolar disorder. Perceived discrimination was measured as the number of patient-reported discrimination events in health care settings. Measured confounders included demographic, socioeconomic, residential and health characteristics. The influence of confounding was denoted as α1 from g-estimation. We compared α1 for measured and unmeasured confounding. Results Strong associations between perceived discrimination in health care settings and mental health outcomes were observed. For anxiety, the odds ratio (95% confidence interval) unadjusted and adjusted for measured confounders were 1.30 (1.21, 1.39) and 1.26 (1.17, 1.36), respectively. The α1 for measured confounding was –0.066. Unmeasured confounding with α1=0.200, which was over three times that of measured confounding, corresponds to an odds ratio of 1.12 (1.01, 1.24). Similar results were observed for other mental health outcomes. Conclusion Compared with measured confounding, unmeasured that was three times measured confounding was not enough to explain away the association between perceived discrimination and mental health, suggesting that this association is robust to unmeasured confounding. This study provides a novel framework to quantitatively evaluate unmeasured confounding.

中文翻译：

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使用 g 估计评估以非裔美国人为主的队列中感知到的歧视与心理健康之间关联的未测量混杂因素


背景 医疗保健环境中的感知歧视可能会对少数群体的心理健康产生不利影响。然而，感知到的歧视与心理健康之间的关联很容易出现无法衡量的混杂。该研究旨在使用 g 估计定量评估未测量的混杂对这种关联的影响。方法 在一个以非裔美国人为主的队列中，我们应用 g 估计来估计感知到的歧视与心理健康之间的关联，根据测量的混杂因素进行调整和未调整。使用焦虑、抑郁和双相情感障碍的临床诊断来衡量心理健康。感知到的歧视是通过医疗保健环境中患者报告的歧视事件的数量来衡量的。测量的混杂因素包括人口统计学、社会经济、住宅和健康特征。混杂的影响从 g 估计中表示为 α1。我们比较了 α1 的测量和未测量的混杂。结果 观察到医疗保健环境中的感知歧视与心理健康结果之间存在很强的相关性。对于焦虑，未经调整和调整的混杂因素的比值比 （95% 置信区间） 分别为 1.30 （1.21， 1.39） 和 1.26 （1.17， 1.36）。测得的混杂的 α1 为 -0.066。α1=0.200 的未测量混杂，是测量混杂的三倍多，对应于 1.12 （1.01， 1.24） 的比值比。在其他心理健康结局中也观察到类似的结果。 结论 与测量的混杂相比，三倍测量的混杂不足以解释感知到的歧视与心理健康之间的关联，这表明这种关联对未测量的混杂是稳健的。本研究提供了一个定量评估未测量混杂因素的新框架。