A study, published in August in the journal Alcohol, focused on how long-term abstinence can undo the effects of cortical thinning in the brain among those with alcohol use disorder.
“Several cross-sectional investigations reported widespread cortical thinning in those with alcohol use disorder (AUD). The few longitudinal studies investigating cortical thickness changes during abstinence are limited to the first month of sobriety. Consequently, cortical thickness changes during extended abstinence in those with AUD is unclear,” the researchers said.
As they explained, cortical thickness “is genetically and phenotypically distinct from cortical volume and surface area,” and that it reflects “the number and density of cells in a cortical column…and/or neuronal cell body size, the number of spines and synapses and the extent of myelination.”
“Cortical thickness may show a differential pattern of recovery with abstinence in alcohol use disorder (AUD) compared to volume and surface area measures in the same brain regions…The cerebral cortex is primarily composed of neuronal and glial cells [i.e., astrocytes, oligodendrocytes, and microglia…and the ratio of glial cells to neurons is approximately 0.7:1; accordingly, cortical thickness may serve as a macroscopic surrogate marker of the cytoarchitectural integrity of cells comprising the cortex,” they wrote in the the study’s introduction.
The researchers also noted that “few studies have investigated cortical thickness changes with abstinence in [alcohol use disorder].”
In their study, the researchers studies participants with alcohol use disorder at one week, one month and a little more than seven months of abstinence.
In this study, AUD participants were studied at approximately 1 week (n=68), 1 month (n=88) and 7.3 months (n=40) of abstinence.
“Forty-five never-smoking controls (CON) completed a baseline study, and 15 were reassessed after approximately 9.6 months. Participants completed magnetic resonance imaging studies at 1.5T and cortical thickness for 34 bilateral regions of interest (ROI) was quantitated with FreeSurfer. AUD demonstrated significant linear thickness increases in 25/34 ROI over 7.3 months of abstinence,” the researchers explained in their summary of the results,, noting that the “rate of change from 1 week to 1 month was greater than 1 month to 7.3 months in 19/34 ROIs.”
“After 7.3 months of abstinence, AUD were statistically equivalent to CON on cortical thickness in 24/34 ROIs; the cortical thickness differences between AUD and CON in the banks superior temporal gyrus, post central, posterior cingulate, superior parietal, supramarginal and superior frontal cortices were driven by thinner cortices in AUD with proatherogenic conditions relative to CON. In actively smoking AUD, increasing pack-years was associated with decreasing thickness recovery primarily in the anterior frontal ROIs,” they continued.
“Widespread bilateral linear cortical thickness recovery over 7.3 months of abstinence was the central finding for this AUD cohort. Proatherogenic conditions were associated with decreased thickness recovery and thinner cortex after 7.3 months of abstinence in several ROIs; this suggests alterations in perfusion or vascular integrity may relate to structural recovery in AUD. These results support the adaptive and beneficial effects of sustained sobriety on brain structural recovery in those with AUD.”
The findings were hailed as “groundbreaking” by PsyPost, saying that the study reveals “a remarkable potential for recovery.”
“There is very limited information in the alcohol use disorder field regarding how human brain structure recovers over longer-term abstinence after treatment,” said Timothy C. Durazzo, a clinical neuropsychologist at the VA Palo Alto Health Care System and professor of psychiatry and behavioral sciences at Stanford University School of Medicine who was one of the authors of the study, as quoted by PsyPost. “Our study is the first to demonstrate significant recovery of cortical thickness in multiple regions in those seeking treatment for alcohol use disorder over approximately 6-7 months of abstinence after treatment.”
Alcohol use disorder is defined as a “a medical condition characterized by an impaired ability to stop or control alcohol use despite adverse social, occupational, or health consequences,” according to the National Institute on Alcohol Abuse and Alcoholism, which said that 28.6 million adults aged 18 and older had alcohol use disorder in 2021.
Genetics, exposure at an early age, mental health conditions and other traumas are all identified as factors that increase the risk of alcohol use disorder.
“It encompasses the conditions that some people refer to as alcohol abuse, alcohol dependence, alcohol addiction, and the colloquial term, alcoholism. Considered a brain disorder, AUD can be mild, moderate, or severe. Lasting changes in the brain caused by alcohol misuse perpetuate AUD and make individuals vulnerable to relapse.The good news is that no matter how severe the problem may seem, evidence-based treatment with behavioral therapies, mutual-support groups, and/or medications can help people with AUD achieve and maintain recovery,” the Institute explained.
