Geographical Analysis of Sudden Infant Death Syndrome (SIDS) and Associated Risk Factors in Douglas County, Nebraska
Caitlin E. Fee and Ariel Tarrell
Background: Sudden Infant Death Syndrome (SIDS) is defined as the sudden and unexpected death of a child less than one year of age without an identifiable cause. Known risk factors of SIDS include prone and side-sleeping positions, bed sharing, male sex, pre- and postnatal tobacco exposure, poverty, prematurity, low birth weight (1
Significance of Problem: In the United States, SIDS is the most common cause of death in infants between one month and one year of age with approximately 2,500 infant deaths caused by SIDS each year.1 The incidence of SIDS has decreased by more than 50% in the last 20 years largely due to the Back to Sleep campaign, which began in 1994. Unfortunately, in Nebraska, the mortality rate of SIDS has been higher than the national mortality rate every year since the campaign began in 1994, except in 2008, 2010 and 2013.2
Questions: If geographically mapped, will SIDS localize to specific regions of Douglas County? If SIDS is localized to specific regions of Douglas County, will associated risk factors concentrate in those areas?
Experimental Design: SIDS rates and known risk factors of SIDS, such as inadequate prenatal care, tobacco use during pregnancy, prematurity, and low birth weight, were geographically mapped in Douglas County, Nebraska using geographical information system (GIS) technology. Data was obtained from the Health Data and Vital Statistics branch of the Douglas County Health Department using birth and death certificates from 2005-2014. Statistical analysis was performed using SAS software version 9.4 (SAS Institute Inc., Cary, NC). P-values less than 0.05 are considered significant. Spearman correlations were used to analyze the associations between SIDS rates and known risk factors. Chi-square or Fisher’s exact tests compared rates in East and West Northeastern regions to best performing regions for each risk factor.
Conclusion: A strategy that aims to lower the rate of SIDS in Douglas County should focus on more accessible first trimester prenatal care and smoking cessation during pregnancy, especially for patients in the East Northeast and West Northeast regions, where these risk factors were significantly different from the best performing regions in Douglas County. By addressing modifiable risk factors such as access to early prenatal care and smoking cessation in areas of demonstrated need, the incidence of preterm births, low birth weights and SIDS in Douglas County could eventually decrease over time.