Research & Publications
My program of research is aimed at refining etiological models of problem substance use in adolescents and young adults by integrating a developmental psychopathology perspective with genetically-informative designs. The identification of differences by gender and race/ethnicity in the contribution of various risk and protective factors to substance use behaviors is central to this pursuit. I study the progression through stages of substance use (e.g., initiation, onset of symptoms) and the timing of stage transitions in relation to socioenvironmental factors such as trauma exposure, neighborhood disadvantage, religious involvement, and discrimination in addition to psychiatric conditions and genetic liability.
Specialized Terms: Alcoholism/alcohol; Substance abuse; Genetic epidemiology; Psychological trauma
Extensive Research Description
Health disparities A major component of the line of research I am pursuing is the identification of distinctions by race/ethnicity in both the course of substance use and the risk and protective factors that influence it. Lower rates of use, lower prevalence of problem or habitual use, and later age at initiation of the use of alcohol and cigarettes in Black compared to White youth and adults - despite higher rates of exposure to risk factors such as trauma - suggest that existing etiological models of alcohol and cigarette smoking do not fit as well for Black youth and adults. The absence of such differences with respect to cannabis use further highlights the need for a more nuanced approach to understanding the development of substance use across racial/ethnic groups, which is essential to developing culturally tailored interventions.
Genetics/familial influences Much of my work on the development of substance use and related problems has made use of twin and other family-based study designs. Investigations conducted with my colleagues have revealed distinctions in the contribution of heritable influences at various stages of substance use. Initiation of substance use is attributable to a significant degree to environmental influences common to family members (e.g., shared peers, parenting practices). Progression to problem use, by contrast, is influenced in about equal parts by genetics and environmental factors specific to an individual (e.g., traumatic events), with little to no shared environmental contributions. These findings indicate that the course of substance use is more malleable in its early stages and that consideration of individual level variability is particularly important for interventions aimed at disrupting the progression from initiation to excessive alcohol or drug use.
Trauma A major goal of my program of research is to elucidate the mechanisms linking childhood trauma to early and problem substance use. I have focused in particular on the role of childhood sexual abuse in the manifestation of familial risk for alcohol related problems in women. Rates of childhood sexual abuse are elevated in offspring of parents with alcohol use disorder, likely due to characteristics of the family environment such as poor parental supervision. Adolescent girls and young women with a history of sexual abuse have often been exposed to a constellation of risk factors, such as parental separation and trauma related psychopathology (e.g., PTSD, depression) in addition to genetic risk for alcohol use disorders. Disentangling this complex pathway is an important step toward reducing risk for substance use disorders in this high-risk population.
CURRENT NATIONAL INSTITUTE ON MINORITY HEALTH AND HEALTH DISPARITIES-SUPPORTED PROJECT
Cultural and Environmental Influences on Precursors to and Early Stages of Alcohol, Nicotine, and Cannabis Use Black and Latinx Youth (PI, R01MD016922) This secondary data analysis project makes use of data from the Adolescent Brain Cognitive Development Study to address three aims:
(1) Characterize dynamic precursors of substance use: Identify patterns in the co-occurrence of (a) cultural and environmental factors that operate at the family level (e.g., familism) and community level (e.g., neighborhood disadvantage) and (b) substance use related cognitions (perceived harm, expectancies, intentions) then examine the links between these two groups of precursors in Black, Latinx, and White youth;
(2) Characterize substance use pathways: Identify similarities/differences in timing, circumstances, and type of alcohol/method of nicotine and cannabis use among Black, Latinx, and White youth;
(3) Capture cultural and environmental sources of variation in substance use pathways: Identify cultural (e.g., ethnic identity) and environmental (e.g., parental monitoring) factors that differentially contribute to experimentation, initiation, and early onset regular use of alcohol, nicotine, and cannabis in Black and Latinx youth.
Alcoholism; Marijuana Abuse; Child Abuse; Psychiatry; Substance-Related Disorders; Healthcare Disparities
Public Health Interests
Genetics, Genomics, Epigenetics; Mental Health; Substance Use, Addiction; Health Equity, Disparities, Social Determinants and Justice