P3.G123: Beyond the Heel Stick: Illuminating Sickle Cell Disease as the Most Prevalent Chronic Condition in Newborn Screening

Background: Sickle cell disease (SCD) is an inherited, autosomal recessive disorder of hemoglobin that causes significant early morbidity and mortality beginning within the first 6-12 months of life. Newborn screening (NBS) for SCD began in the 1980s, but was not universally screened for in all fifty states until 2006. Even with this delay, the early diagnosis and introduction of comprehensive care have contributed to a significant reduction in early mortality. Because SCD affects a minoritized population in the US due to the genetic origins as a protective mechanism against malaria, SCD is still often considered to be rare and is not prioritized in most healthcare systems. In this study, we aim to describe the prevalence of SCD identified by NBS across the US in comparison to other commonly-screened conditions. We hypothesized that SCD is among the most common chronic conditions detected by NBS, regardless of race or ethnicity, and should be prioritized as such.

Methods: We used data from the Newborn Screening Technical Assistance and Evaluation Program (NewSTEPs), a NBS resource center that collects aggregate case data from all 50 states, Washington DC, Guam, and Puerto Rico. State-level data were analyzed but aggregate regional data were reported to protect patient privacy. The annual birth prevalence of SCD, congenital hypothyroidism, phenylketonuria (PKU), and cystic fibrosis in the US were each calculated and averaged over a five-year period (2016-2020).

Results: Between 2016-2020, 9597 infants were born with SCD, equivalent to approximately 5 infants with SCD born daily. The overall birth prevalence of SCD (all genotypes) was 1 in 1988 nationally, with distinct geographical differences. SCD was most common in the Southeast Region (1 in 1161), the New York-Mid-Atlantic Caribbean Region (1 in 1486) and the New England Region (1 in 2190) (Figure). Overall, SCD was the second most detected condition on NBS, only outnumbered by congenital hypothyroidism (1 in 1582 prevalence). However, as 20-50% of infants who have abnormal thyroid studies at birth do not require replacement thyroid hormone beyond the first few years of life, SCD is arguably the most common chronic condition identified by NBS. SCD was significantly more common than all other screened conditions on NBS regardless of race/ethnicity and was more than twice as common as cystic fibrosis (1 in 4657) and more than 7 times as common as PKU (1 in 14390).

Conclusion: SCD is the most common chronic condition detected by NBS in the United States regardless of race/ethnicity and should be contextualized and prioritized as a common genetic condition without further racialization. The development of long-term centralized NBS follow-up programs is essential to further describe the overall burden of SCD in the US to stimulate allocation of resources to this marginalized and vulnerable population.