Structural Brain Effects of Alcohol Use Patterns in Alcohol Use Disorder: A Systematic Review and Meta-Analysis

Alcohol use disorder (AUD) is associated with significant structural alterations in gray and white matter of the brain, which has potential implications for cognitive and emotional functions. These alterations appear to be related to alcohol use patterns. This study aims to systematically review voxel-based morphometry studies to identify consistent patterns of gray matter and white matter alterations in patients with AUD compared to healthy control subject and explore their associations with alcohol consumption patterns. A systematic review of neuroimaging studies was conducted, analyzing gray matter (GM) and white matter (WM) differences between healthy individuals and patients with AUD. Special attention was given to the relationship between alcohol consumption variables (e.g., duration, quantity, frequency) and GM and WM volumes. AUD patients showed significant GM alterations in the right cingulate (SDM-Z = -6.013), right insula (SDM-Z = -6.088) and left Heschl gyrus (SDM-Z = -5.254) compared to healthy control subject. WM alterations were found in the corpus callosum (SDM-Z = -3.537). Meta-regressions revealed dose-dependent associations: AUDIT scores (SDM-Z = -3.143), drinks/day (SDM-Z = -3.504), lifetime drinking (SDM-Z = 3.460), and years of dependence (SDM-Z = 3.063) were each negatively correlated with regional GM volume. Earlier age at first drink was associated with WM volume in the corpus callosum (SDM-Z = 3.229). Longer abstinence was correlated with larger WM volumes. This meta-analysis underscores the associations between alcohol consumption patterns and brain structure and provides evidence of dose-dependent associations between alcohol consumption and neuroanatomical differences.