(227) Regional health unit presence by parish and congenital syphilis rate in Louisiana

Health units in Louisiana parishes serve as regional access points of essential health services, including screening, treatment, and prevention of syphilis. Clinic location is varied; some parishes have two while others have none. The increased congenital syphilis rate highlights the potential of these state-run clinics to target localities with high burdens of syphilis. We hypothesize that residing in a parish without a health unit increases risk for maternal and congenital syphilis.


Study Design:

We performed a retrospective cohort study of pregnancies receiving prenatal and delivery care from 2015 to 2023 in a large health system in Louisiana. Historical and prenatal laboratory values determined syphilis infection status. Patients were compared based on the presence or absence of a health unit in the parish of their home address. The primary outcome was congenital syphilis (CS), as defined by Centers for Disease Control case criteria. A subanalysis of CS limited to maternal syphilis cases was performed. Regression analysis controlling for payor status generated adjusted odds ratios with 95% confidence intervals.


Results:

A total of 42,684 pregnancies were included, of which 25.7% resided in a parish with no health unit. Patients in health unit parishes were younger, more likely to use public insurance and more likely to reside in a high-deprivation neighborhood (Table 1). No difference in CS cases were observed between groups (0.1% vs 0.1%, aOR 1.60, CI 0.75 – 3.93). New maternal syphilis infections were less common in parishes without health units (0.3% vs 0.7%, OR 0.38, 95% CI 0.26 – 0.56). When limiting analysis to maternal syphilis cases, living in a parish without a health unit was associated with increased odds for CS (51.6% vs 16.5%, aOR 5.42, 95% CI 2.47 – 11.88).


Conclusion:

Parishes with health units had higher area deprivation and higher public insurance, and were associated with increased maternal syphilis infections. Syphilis during pregnancy in non-health unit parishes was associated with substantial increased odds for congenital syphilis compared to health unit parishes.