Dr. Wenna Xi, instructor of population health sciences, has been awarded a K99/R00 grant from the National Institute of Mental Health (NIMH) for her study on risk and protective factors for Black youth suicide and suicidal ideation and behaviors (SIB).
The K99/R00 Pathway to Independence Award helps facilitate the transition from a mentored postdoctoral research position to anindependent research position. The K99 phase provides mentored support, while the R00 phase provides up to three years of independent support.

Dr. Xi joined the department as a postdoctoral associate, working with Dr. Samprit Banerjee, associate professor of population health sciences, and Dr. Jyotishman Pathak, chief of the Division of Health Informatics and Frances and John L. Loeb Professor of Medical Informatics. She worked on Dr. Pathak’s R01 grant for predicting self-harm, suicide attempts, and suicidal death, and was primarily involved in using commercial health insurance claims data to study suicide. This postdoctoral experience with the subject of mental health motivated her to specifically study suicide among Black youth in the U.S.
Rates of suicide and SIB among Black youth have almost doubled in the past decade, as compared to their white counterparts. Additionally, alcohol consumption and marijuana use have been positively associated with suicidal ideation in Black youth, but not for their white or Hispanic counterparts. However, previous studies have not focused solely on risk modeling for Black youth. In her study, Dr. Xi will study suicide and SIB among Black youth aged 10 to 24 by considering individuals’ medical history, geographic residential locations, and neighborhood-level social integration level.
“When you study suicide in Black communities, the rate is typically low,” she explained. “Cultural resilience is often a protective factor for them. When you look at other populations, that cultural resilience is sometimes missing. It’s important, then, to determine why the suicide rate for Black youth has increased dramatically.”
In the K99 phase of her study, Dr. Xi proposes to use machine learning models to identify risk and protective factors for suicidal ideation (SI), suicide attempts (SA), and suicide death (SD). She also plans to evaluate sociologist Emile Durkheim’s social integration theory on Black youth suicide and SIB. The theory suggests that the more socially integrated a person is, the less likely they are to end their life. To evaluate the theory, she plans to construct and validate a novel social integration index.
During the R00 phase, Dr. Xi will evaluate sociologist Gabriel Tarde’s imitation theory in conjunction with Durkheim’s social integration theory, and their effects on Black youth suicide and SIB prevention. In his studies, Durkheim observed geographic clusters of suicide cases. Correspondingly, Tarde’s theory suggests that humans in neighboring areas adopt one another’s behaviors and beliefs.
“In the R00 phase, I will evaluate whether Tarde’s imitation theory explains what social integration theory cannot,” she said. “My hypothesis is that both the imitation theory and integration theory are playing a role in suicidality. This phase will involve visualizing the data on maps and summarizing the geographic clusters and temporal changes in the clusters of SI, SA, and SD.”
In place of less plausible experiments that would modify imitation and social integration, Dr. Xi will use causal inference to assume the extent to which risk factors can be reduced. She hypothesizes that increasing social integration and leaving suicidal clusters could potentially reduce Black suicide and SIB risks.
Prior to joining the department, Dr. Xi never thought about studying mental health, and is grateful to both Dr. Pathak and Dr. Banerjee for their guidance as she explores the field. She describes them as pivotal to building her experience with the subject, as well as with EHR and claims data. She hopes to become a primary investigator in the future, and to make youth mental health a focal point of her career.
“I really believe that youths are the future,” she said. “And my interest is especially in marginalized youth: youths of color, undocumented youth, youths from low-income backgrounds. They certainly don’t have enough resources compared to other kids, and we need to advocate for them.”