Owerko Centre, Alberta Children's Hospital Research Institute, University of Calgary, #355, 3820 24th Ave, Calgary, AB, T3B 2X9, Canada.
Department of Psychology, University of California Los Angeles, Los Angeles, CA, USA.
J Racial Ethn Health Disparities. 2019 Dec;6(6):1182-1191. doi: 10.1007/s40615-019-00619-3. Epub 2019 Jul 31.
Higher socioeconomic status (SES) has less impact on cardio-metabolic disease and preterm birth risk among Black women compared to White women, an effect called "diminishing returns." No studies have tested whether this also occurs for pregnancy cardio-metabolic disease, specifically preeclampsia, or whether preeclampsia risk could account for race-by-SES disparities in birth timing.
A sample of 718,604 Black and White women was drawn from a population-based California cohort of singleton births. Education, public health insurance status, gestational length, and preeclampsia diagnosis were extracted from a State-maintained birth cohort database. Age, prenatal care, diabetes diagnosis, smoking during pregnancy, and pre-pregnancy body mass index were covariates.
In logistic regression models predicting preeclampsia risk, the race-by-SES interaction (for both education and insurance status) was significant. White women were at lower risk for preeclampsia, and higher SES further reduced risk. Black women were at higher risk for preeclampsia, and SES did not attenuate risk. In pathway analyses predicting gestational length, an indirect effect of the race-by-SES interaction was observed. Among White women, higher SES predicted lower preeclampsia risk, which in turn predicted longer gestation. The same was not observed for Black women.
Compared to White women, Black women had increased preeclampsia risk. Higher SES attenuated risk for preeclampsia among White women, but not for Black women. Similarly, higher SES indirectly predicted longer gestational length via reduced preeclampsia risk among White women, but not for Black women. These findings are consistent with diminishing returns of higher SES for Black women with respect to preeclampsia.
与白人女性相比，黑人群体中较高的社会经济地位（SES）对心血管代谢疾病和早产风险的影响较小，这种现象被称为“收益递减”。目前尚无研究检验这种现象是否同样适用于妊娠心血管代谢疾病，特别是子痫前期，或者子痫前期风险是否可以解释出生时间方面种族与 SES 差异的原因。
从加利福尼亚州一项基于人群的单胎妊娠队列中抽取了 718604 名黑人和白人女性作为样本。从州级维护的出生队列数据库中提取了教育程度、公共健康保险状况、妊娠时长和子痫前期诊断信息。年龄、产前保健、糖尿病诊断、孕期吸烟和孕前体重指数是协变量。
在预测子痫前期风险的逻辑回归模型中，种族与 SES 的交互作用（包括教育和保险状况）具有统计学意义。白人女性发生子痫前期的风险较低，SES 越高，风险越低。黑人女性发生子痫前期的风险较高，SES 并不能降低风险。在预测妊娠时长的路径分析中，观察到种族与 SES 交互作用的间接效应。在白人女性中，SES 越高，预测子痫前期风险越低，进而预测妊娠时长越长。而这一现象在黑人女性中并未观察到。
与白人女性相比，黑人女性发生子痫前期的风险更高。SES 越高，白人女性发生子痫前期的风险越低，但黑人女性并非如此。同样，SES 越高，通过降低子痫前期风险，间接预测白人女性的妊娠时长越长，但黑人女性并非如此。这些发现与 SES 对黑人女性子痫前期的收益递减效应一致。
