230 - County-level social vulnerability index and extremely preterm infant mortality rate in the western region of the United States

Publication Number: 230.4177

Nihaal D.. Shah, Valley Children's Healthcare, Madera, CA, United States; Fredrick Dapaah-Siakwan, Valley Children's Healthcare, Madera, CA, United States

Background: Previous research shows that there is increased risk of preterm birth in communities with high social disadvantage but it is unknown if community social disadvantage is associated with increased preterm mortality.

Objective: To examine the association between of the county-level social vulnerability index and extreme preterm infant mortality rates (EPIMR) in the Western United States (US).

Design/Methods: In this cross-sectional study, we linked the county-level EPIMR from 2018-2022 obtained from the CDC’s Wide-Ranging Online Data for Epidemiologic Research database with 2022 county-level social vulnerability index (SVI) from the Agency for Toxic Substances and Disease Registry. The data was limited to counties in the Western US (AL, HI, CA, OR, WA, ID, CO, NV, UT, AZ, NM, WY). Counties with death counts < 10 or population < 100,000 were excluded. The SVI measures social determinants of health in US counties based on 16 social attributes, which are categorized into 4 Themes [socioeconomic status (Theme 1), household characteristics (Theme 2), racial/ethnic minority status (Theme 3), housing type/transportation (Theme 4)]. The overall SVI data and the sub-themes were scored from 0-1 and each was divided into quartiles (SVI-Q1: least vulnerable; SVI-Q4: most vulnerable) based on their distribution. We then calculated the average EPIMR with 95% confidence intervals (95% CI) for each quartile for the overall SVI and each of the sub-themes. EPIMR was expressed as per 1,000 livebirths. SVI-Q1 was compared to SVI-Q4 and any difference was considered significant if the 95% CI did not overlap.

Results: Overall, average average EPIMR from 2018-2022 was 233.2 per 1,000 live births (95% CI: (222.6 - 243.8). For overall SVI, there was no significant difference in the average EPIMR between SVI-Q1 (235.2; 95% CI: 217.8–252.6) and SVI-Q4 (210.4; 95% CI: 202.1–218.6). For Theme 1 (socioeconomic status), there was no significant rate difference between the EPIMR for SVI-Q4 and SVI-Q1 as shown in Table 1. Similarly), there was no significant rate difference between the EPIMR for SVI-Q4 and SVI-Q1 for Themes 2, 3, and 4.

Conclusion(s): There was no significant relationship between county-level SVI and extremely preterm infant mortality rates in the western region of the United States.

Table 1: County-level social vulnerability index quartile and extreme preterm infant mortality rate in the Western United States.
πRate difference not significant due to the 95% confidence intervals of SVI-Q4 overlapping with that of SVI-Q1