Abstract Body: Introduction:
Previous research has shown associations between individual social risks and hypertensive disorders of pregnancy (HDP), but less is known about the cumulative effect of multiple social risks. This study examines the association between cumulative social risks (CSR) and the risk of HDP among pregnant women using data from the National Inpatient Sample (NIS)Methods:
A retrospective cross-sectional analysis of pregnant women hospitalized between 2016 and 2021 was conducted using the NIS. HDP were modeled as a binary variable, identified using ICD-10 codes. The main exposure, CSR, was derived by summing social risk factors: median zip code income (≤50th percentile vs. >50th percentile), rurality (urban vs. rural), region of hospital (South, Midwest vs. Northeast, West), insurance type (government insurance vs. commercial/private insurance), patient residence location (urban vs. rural), and race (minority race vs. White). Univariate analyses were performed to examine the association between each social risk factor and HDP. Survey weighted multivariable logistic regression models were used to assess associations between HDP across different levels of CSR, adjusting for age and patient location. An interaction term and predicted margins were used to assess if the association of CSR and HDP changed over the study period.
Results:
Among 4,482,956 pregnant women (mean age: 29 5 ± 9), those in the 0-25th income percentile had 29% higher odds of HDP (OR=1.29, 95% CI: 1.27-1.32) compared to those in the ≥76th percentile. Rural women had 20% lower odds (OR=0.80, 95% CI: 0.78-0.81) compared to urban women. Black women had 56% higher odds of HDP (OR=1.56, 95% CI: 1.54-1.58) compared to White women, while Hispanic women had lower odds (OR=0.83, 95% CI: 0.81-0.84). In multivariable logistic regression models adjusted for age and calendar year, women with 4 or more cumulative social risks had significantly higher odds of HDP (OR=1.39, 95% CI: 1.31-1.48) compared to those with no risks. Predicted probabilities increased across social risk levels over the study period, with women at the highest risk showing a 20.05% probability of HDP in 2021 (95% CI: 19.51%-21.44%).
Conclusion:
Cumulative social risks have a progressively stronger impact on HDP over time, suggesting that worsening social inequities are exacerbating maternal health disparities. Targeted interventions addressing social risks are critical to mitigating HDP risk, especially among underserved populations.