ArticlemedRxiv : the preprint server for health sciences2026
Brain Structure and Substance Use: Disentangling Risk, Exposure, and Drug-Specific Effects.
Article in medRxiv : the preprint server for health sciences, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
0 citing papers in PubMed.
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Corrections and comments
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Authors and funding
2 authors.
Funding
Abstract
Importance: Polysubstance use is common, but substance use associations with neuroimaging measures have largely been investigated within individual drug types. Whether effects are substance-specific or -general, and how predispositional risk and exposure contribute, remains unclear. Objective: Identify shared and unique associations between substance use and brain structure, and characterize the contributions of predispositional risk and environmental exposure, in a large sample of young adults in the US. Design: This cross-sectional family-based study used data from the Human Connectome Project (2017 release, collected from 2012-2015). Setting: Data were collected at Washington University in St. Louis, MO, USA. Participants: Twins, non-twin siblings, and singletons with magnetic resonance imaging (MRI) and substance use self-report were included in the analysis. Data were analyzed in 2025. Exposure: History of substance use was assessed using the Semi-Structured Assessment for the Genetics of Alcoholism. Variables included lifetime use, heavy or past-year hazardous use, and age of use onset for alcohol, marijuana, tobacco, and illicit drugs. Additionally, alcohol and marijuana dependence were assessed. Main Outcomes and Measures: Linear mixed-effect models examined associations between substance use and brain structure, with an initial focus on past-year hazardous alcohol use, as 95% of the sample endorsed lifetime alcohol use. Analyses then tested associations with other substance use variables, and whether effects were shared or substance-specific. Between-family, within-family, and genetic variance component analyses tested risk and exposure effects. Results: 1,113 participants (N = 445 families; ages 22 - 37; Conclusions and Relevance: Brain structural associations with substance use reflect substance-general and -specific effects, as well as a combination of predispositional and exposure effects. Findings suggest that the negative consequences of polysubstance use may reflect the additive effects of multiple unique exposures.
Identifiers
What Socratic holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.