SIDS discovery could ID babies at risk of sudden death

The findings also represent an important step forward in unraveling the causes of SIDS, an unexplained condition that is the No. 1 killer of babies between amonth and a year old.

The UVA researchers analyzed blood serum samples collected from infants who died from SIDS and were able to identify specific biological indicators that were linked to -- and potential causes of -- the babies' deaths.

Tests to identify such signs in infants could ultimately help save lives, the researchers say.

"Our study is the largest study to date that has attempted to detect how these small molecules in the blood may serve as biomarkers for SIDS," said researcher Keith L. Keene, PhD, founding director of UVA's Center for Health Equity and Precision Public Health and now at East Carolina University. "Our findings support a role for multiple key biological pathways and provide insight into how those biological processes may contribute to increased risk or serve to diagnose SIDS."

Understanding SIDS

The new research speaks to the potential of "metabolomics," the analysis of substances called metabolites produced by cells, for better understanding and treating complex diseases, the scientists say.

In their SIDS work, the UVA researchers analyzed blood serum samples collected from 300 babies included in the Chicago Infant Mortality Study and the National Institutes of Health's NeuroBioBank. The researchers assessed levels of 828 different metabolites in key biological processes such as nerve cell communication, stress response and hormone regulation -- processes that could be contributors to SIDS.

After adjusting for factors that could bias the results, such as the infants' age, sex, and race and ethnicity, the researchers identified 35 predictors of SIDS. These "biomarkers" included ornithine, a substance critical to the body's ability to dispose of ammonia in urine. The amino acid has already been identified as a potential contributor to SIDS.

Another predictor was a lipid metabolite that is critical for brain and lung health. This metabolite is already considered a potential indicator for the development of fetal heart defects during the first trimester of pregnancy.

"We found differences in specific fats, called sphingomyelins, which are critical for brain and lung development," said researcher Chad Aldridge, DPT, MS-CR, of the School of Medicine's Department of Neurology. "Differences in these fats may disrupt these critical processes, placing some infants at risk for SIDS."

The UVA scientists caution that further research is needed to determine if the metabolites are contributing to SIDS. But the findings lay an important foundation, they say, for unraveling the mysteries of SIDS and developing blood tests that could potentially save new parents from heartbreak.

"The results of this study are very exciting -- we are getting closer to explaining the pathways leading to a SIDS death," said researcher Fern R. Hauck, MD, MS, a family medicine physician at UVA Health, director of the Chicago Infant Mortality Study and aleading expert on SIDS. "Our hope is that this research lays the groundwork to help identify -through simple blood tests -- infants who are at higher risk for SIDS and to save these precious lives."