The built environment, referring to the surroundings and physical artifacts of where humans live, is considered to be one of the five major social determinants of health (SDoH).(1) The built environment determines housing quality, mode of transportation, and exposure to pollutants, effectively influencing our way of life.(2) Poor built environment causes adverse effects on physical and mental health by disrupting sleep, hindering healthy life styles, and lowering access to healthcare.(3–5) There is a gender difference on the association between the built environment and health. Mullings et al. reported an increased risk of depression among female associated with living in an unplanned neighborhood characterized by inadequate sewer treatment, water supply, and dependable supply of electricity.(6) Furthermore, the Chicago Community Adult Health Study found the women’s use of preventive care to be associated with objective and perceived neighborhood support and stressors such as odors, presence of trees, and noise levels.(7)
The existing literature motivated this study to examine the impact of the built environment on health and healthcare utilization among women, and particularly, the pregnant population.(8–10) Levels of prenatal care vary across the United States.(11–13) A substantial proportion of pregnant women, in particular those with a higher comorbidity burden or low health literacy, seek and depend on care provided by emergency departments (ED) rather than primary and obstetric care.(13–15) The lack of adequate prenatal care is considered to be a risk factor for poor pregnancy outcomes and lack of proper postpartum care for mothers and infants.(16) Previous studies have studied the built environment on maternal health and birth outcomes including birth weight, gestational age, Apgar score, and newborn intensive care unit admission rates.(5, 17) Yet, evidence is still accumulating on how the built environment affects the variability in prenatal care and maternal mental health outcomes. In particular, few studied the concurrent impacts of prenatal care and built environment on mental health outcomes. Existing studies have commonly relied on the subjective perceived measures obtained from interviews and questionnaires.(4, 7, 18) However, relying on subjective measurements may increase recall bias which occurs when some participants recall the exposure differently than others.
In this study, we hypothesize that the built environment, through influencing the accessibility to transportation, green space, safe neighborhood, and other urban structure, is associated with variability in prenatal care and subsequent maternal mental health outcomes.
Given findings from previous literature on the impact of the built environment on women’s mental health and use of healthcare, we defined postpartum depression (PPD) as our primary outcome.(
19) PPD has been associated with increased infant mortality, higher rates of hospitalizations, impaired mother-child attachment, developmental problems in children, and increased stress within families.(
20–
23) The plethora of physical and psychological effects of PPD reported in previous studies include postpartum weight retention, reduced physical health, bodily pain, anxiety, low self-esteem, risky addictive behavior of substances, and suicide ideation.(
24) The biological risk factors of PPD include genetic factors, age, pregnancy complications, medical illness, and smoking during pregnancy.(
4,
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27) The social, cultural, and environmental risk factors include income status, domestic violence, lack of social support, quantity and quality of green spaces, and residential noise pollution.(
26,
28–
32)
We tested our hypotheses by linking patients’ health data extracted from de-identified electronic health records (EHRs) with publicly available census-tract level data on the built environment. Routinely collected from clinical encounters, EHR data capture detailed longitudinal health data on health and health service utilizations. Increasingly, EHR data have been used as a source of longitudinal data in population health studies for its ability to provide detailed and rich health information within patient cohorts.(33) Leveraging a large cohort of nearly 9,000 women in New York City from 2015 to 2017, we applied machine learning algorithms to EHR data to identify patterns in prenatal care.(34) We then evaluated the relationships among prenatal care patterns, PPD incidence, and the built environment using structural equation modeling.(35) The association found may inform patients, care providers, and public health policy makers in supporting healthy pregnancy and new motherhood.