Team ARIA

By Raina Patel

Hello friends! The blog has been quiet, but we’ve been very busy!  Take a look below at a project we recently completed.  A brief summary of this work and a resource guide can be found here:

Ever wonder about how alcohol use and alcohol use disorder develop?  So did a group of researchers at Virginia Commonwealth University. A research team made up of VCU faculty and students, led by Dr. Christina Sheerin, tried to understand the role of possible risk factors on alcohol use behaviors such as average alcohol consumption and alcohol use disorder (AUD) in college students over the age of 18.

Why? Alcohol use is common in the college environment and could have negative consequences during college and later in life. Alcohol use may lead to the development of AUD, a condition involving frequent or heavy alcohol drinking that becomes difficult to control and leads to problems such as in relationships, work, school, family, or other areas (Das & Kidd). Between 2012-2013, 30.7% of college students met the criteria to be diagnosed with AUD making it a common mental health problem (Arterberry et. al., 2020).

Since many young adults ages 18-25 experiment with alcohol use during college, the authors thought it might be helpful to understand factors associated with alcohol use behaviors during this important stage in life course development. Exposure to traumatic events is also common in this age group. Additionally, the research team wanted to understand the degree to which genetic risk and environmental factors like trauma exposure work together to influence two related alcohol use behaviors–maximum alcohol consumption and AUD. The authors chose to study these two alcohol use behaviors because not all college students who drink are affected with AUD and they wanted to understand whether the genetic and environmental risks would impact in a similar manner for alcohol behaviors.

How? The authors chose to study three major factors that they thought might be associated with alcohol use behaviors: biological sex, exposure to interpersonal trauma, and genome-wide measures of risk associated with alcohol use behaviors. In this study, IPT reflected a participant’s report of having experienced physical assault, sexual assault, or other unwanted touching/sexual experience. The team used data from Spit4Science, an ongoing study of multiple cohorts of students attending an urban, Mid-Atlantic public university who completed online surveys and who provided saliva samples to share their DNA for research studies.

What Did They Find? The team reported several results:

The team determined that out of the 9,006 people who participated in the study, 30.3% met the symptoms for being diagnosed with AUD. They also found that the prevalence of AUD was strikingly similar between males (30%) and females (30.3%).

About 37.2% of participants in the study experienced interpersonal trauma (IPT) before attending college.

Exposure to IPT differed between females and males – more female participants (40.6%) experienced some form of IPT compared to male participants (31.3%). Participants who experienced IPT tended to consume more alcohol than those who never experienced it. Additionally, participants who experienced IPT, compared to those who did not, were 1.12 times more likely to be diagnosed with AUD during college.

The team also tested the degree to which genome-wide polygenic scores (PGS) for alcohol use were associated with alcohol use behaviors. Polygenic scores were estimated for each participant in the study using the DNA participants shared with the study from their saliva. The PGS uses thousands of genetic variants throughout a participant’s DNA (also known as their “genome”) to produce a summary measure that reflects the effect of all the measured genetic variants on alcohol use behavior. The team wanted to study the role of genetic factors on alcohol use behaviors in addition to IPT because there is evidence to indicate that genetic and environmental factors often work together to lead to alcohol use behaviors. It is currently unclear whether specific environments, such as experiencing IPT, work with genetic factors to influence alcohol behaviors. The results of the data analysis from the study indicated that the PGS significantly was associated with alcohol consumption as well as AUD.

Although the team identified significant associations between alcohol use behaviors and IPT as well as PGS, their results did not support that the association of PGS predicting alcohol use behaviors did not depend on or differ if the individual experienced IPT or not.

Why Does This Work Matter? This study has several strengths. This study examined both genetic and environmental risk factors during young adulthood (ages 18-25 years old), a vulnerable time period in human development. Second, this study assessed multiple alcohol use behaviors rather than a single measure. This is important because the team was able to conclude that for this study sample, IPV influences alcohol use behaviors similarly whether measured as alcohol consumption (which reflects a less severe behavior) or AUD (a more severe alcohol use behavior). Third, this team conducted a meta-analysis of PGS associations across all participants representing all genetic ancestry groups rather than focusing solely on an European ancestry-only population. This is important because most earlier studies have focused on the use of genomic data from participants defined as “European ancestry”. These studies often did not include data from participants defined as belonging to other ancestry groups (e.g., African, East Asian) as their data, even when collected, are often not included in analyses because they generally do not have enough statistical power to make strong conclusions because the sample sizes are much smaller. The practice of not including all populations limits the generalizability of the research results to only the population studied (e.g., often only European ancestry). This lack of inclusion has downstream consequences that additional translation of results into prevention and intervention strategies are not beneficial to all. This study intentionally addressed this issue by making an analysis plan that included data from all available participants.

What’s Next? The research team concluded that exposure to IPT was associated with both alcohol consumption and AUD, but there was limited evidence for statistically significant interactions between sex and IPT. The absence of differences in the association between IPT and alcohol use behaviors by sex encourages future prevention activities to consider the ways in which various factors such as advertising, policies, attitudes towards alcohol use, peers, and family alcohol behaviors might influence males and females in the same way. The association between PGS and alcohol behaviors indicates the importance of genetic factors on both alcohol consumption and AUD. These results may encourage community-level discussion about the importance of genetic factors in alcohol behavior development in young adult populations. Although an individual’s genetic risk for alcohol behaviors cannot be changed, an awareness of such risk may help to provide personal context for an individual as they consider their drinking habits and potential behavior change. Future research is needed to determine how best to include a discussion of measures like polygenic scores for alcohol use to prevent problematic alcohol use.

Future researchers are encouraged to determine whether this pattern of association is consistent in other stages of development, in population-based samples beyond college students, using other measures of IPT, using other measures of alcohol use behaviors, and in even larger and diverse samples of participants across genetic ancestry as well as socioeconomic factors.

For more information on the study, visit https://www.frontiersin.org/articles/10.3389/fgene.2023.1274381/full