Connectivity studies through MRI for alcohol dependent patients to identify biomarkers

Diffusion magnetic resonance imaging is a powerful tool used to study brain structures and connectivity. It has been widely employed in evaluating the impact of alcohol use disorder. This study focuses on investigating the relationship between structural connectivity changes observed during abstinence and the corresponding changes in behavioral measures. The research was conducted on a group of 73 patients to gain insights into biomarkers of behavioral recovery during abstinence by studying structural brain connectivity. The subjects underwent three scans: one on the first day of an abstinence program, a second 18 days later, and a third three months later. The connectome-based predictive model designed by Shen et al. was applied on structural brain connectivity data obtained from tractograms to quantify brain-behavior relationships. The behaviors studied are depression, obsessive-compulsive disorders, state and trait anxiety, and multidimensional fatigue, which are known to be affected by alcohol consumption. Obsessive-compulsive disorders measures were divided into cravings of alcohol, obsessions, and compulsions. A progressive evolution of the behavioral measures towards the controls has been observed during the first three months of abstinence. Moreover, the selected biomarkers revealed a predominance of the left hemisphere in predicting the evolution of behavioral measures during abstinence. Depression was primarily associated with parietal regions, while also involving the left lateral occipital white matter and the left transverse temporal white matter. Temporal and occipital regions played a significant role in state and trait anxiety. Biomarkers for multidimensional fatigue were predominantly located in the left temporal and parietal regions, with the left paracentral white matter also identified as influential. For cravings and compulsions, the left superior parietal cortex, brain stem, and left precuneus cortex were identified as biomarkers. Additionally, the right choroid plexus and right banks of the superior temporal sulcus emerged as biomarkers for cravings, whereas the right hippocampus and left transverse temporal white matter were associated with compulsions. In the case of obsessions, the brain stem, mid posterior corpus callosum, left superior temporal cortex, right insular cortex, and left thalamus proper were identified as biomarkers. These findings align with the known functions of the identified regions, as well as with the known regions altered by AUD or involved for the behaviors studied. Biomarkers of behavioral recovery in patients suffering from alcohol use disorder during abstinence can thus be identified.