Characteristics Associated with Sudden Unexpected Infant Death in a Rural Hispanic Population: A Case-Control Study

Sudden unexpected infant death (SUID) is the leading cause of death among U.S. infants aged 28 days to 1 year. In Kansas, Hispanic infant mortality is nearly 50% higher than non-Hispanic White. Further, the SUID rate did not change between 2005-2018, while rates for non-Hispanic Black and White infants decreased significantly. This study sought to identify characteristics and behaviors of Hispanic birthing persons related to SUID.

Linked Kansas birth/death vital statistics data (2005-2018) identified Hispanic birthing persons with a singleton birth who experienced SUID. To reduce confounding effects, greedy nearest neighbor matching paired each SUID case sequentially with the four nearest controls based on age, race, payor source and parity. Matching procedures, likelihood-ratio χ2, Fisher exact test and multiple logistic regression model with Firth's penalized maximum likelihood estimation were computed.

Of 86,052 Hispanic singleton births, 66 involved SUID and were matched with 264 controls. No differences were related to marital status, population density of residence, education level, language spoken, prenatal BMI, weight gained during pregnancy, adequacy of prenatal care, enrollment in WIC, or state immunization registry participation (all p>0.05). However, tobacco use during pregnancy contributed to a three times greater risk of SUID (OR=3.208; 95% CI=1.438 to 7.154). Multivariable models for behavioral variables revealed low predictive accuracy with area under the ROC curve=0.6303.

This study suggests SUID deaths to rural Hispanic families are likely multifaceted. Study results inform educational programs on the importance of addressing tobacco cessation in SUID risk reduction interventions for Hispanic families.