Lead is a well-known neurotoxicant, with lead exposure accounting for 63.8% of the global burden of idiopathic developmental intellectual disability. Importantly, lead exposure does not occur in isolation, but coexists with other social risk factors, such as low socioeconomic status, that influence neurodevelopment and impact similar neurocognitive outcomes. Impaired neurocognition, such as decreased IQ and working memory, can lead to poor health behaviors and outcomes in adolescence and adulthood. Because of this, it is critical to understand how childhood lead exposure and social risk factors interact to influence later neurocognition and examine the biological mechanisms within this relationship. This fellowship application will give the applicant the necessary training and research experiences to become an independent nurse researcher with developing expertise in lead exposure, social risk factors, biological stress, neurodevelopment, and advanced methodological and analytical skills. This foundational training is critical for the applicant to achieve her career goal of becoming an independent nurse researcher examining longitudinal relationships. The applicant will conduct a secondary data analysis to examine the interaction effect of childhood lead exposure and social risk factors on adolescent neurocognitive outcomes and explore sustained biological stress as a shared mechanism of action for that relationship. There is prior empirical support for the interaction effect of childhood lead exposure and social risk factors on adolescent neurocognition and theoretical support for the mediating effect of sustained biological stress on this relationship, but further empirical testing is needed.
The specific aims of this study are to: 1) Examine the interaction effect of childhood lead exposure and social risk factors on adolescent neurocognition 2) Assess the relationships between childhood lead exposure, social risk factors, and adolescent heart rate variability during a stress test (a marker of sustained biological stress), and 3) Examine low heart rate variability (sustained biological stress) as a mediator for the relationship between childhood lead exposure, social risk factors, and adolescent neurocognition. This study will analyze data from the Jintan China Child Cohort Study using multiple linear regression and path analysis methods. The applicant will also complete an individualized training plan, including coursework and research experiences, to guide her in achieving her training goals. This study will be an initial step in a program of research to understand the interrelationship of childhood lead exposure and social risk factor?s influence on neurocognition and to develop interventions to improve the neurocognitive outcomes of children exposed to lead. This proposal aligns with the National Institute of Nursing Research?s mission of enhancing wellness through understanding the environmental influences on behavior and by examining biological mechanisms of symptoms such as cognitive impairment.
Childhood lead exposure and social risk factors continue to impair children?s neurocognition and health decision making behaviors world-wide. Given lead exposure and social risk factors often coexist, it is crucial to understand how they interact to impair neurocognition as well as understand what may cause these neurocognitive impairments. This study will examine how these risk factors interact and contribute to neurocognitive deficits, which will help to identify points of intervention to improve the neurocognitive outcomes of lead exposed children.
