Booze carries on damaging people’s brains even after they stop drinking, according to new research.
The idea grey matter returns to normal immediately after stopping hitting the bottle is a myth, say scientists.
Structural damage to white matter – that helps neurons communicate – goes on for weeks.
The finding was based on 90 voluntary patients on a rehabilitation treatment programme at a hospital in Germany.
Magnetic resonance imaging (MRI) scans showed six weeks after stopping drinking there were still changes in the brain.
Study co-ordinator Dr Santiago Canals, of the Spanish National Research Council in Alicante, said the results were surprising.
He said: “Until now, nobody could believe that in the absence of alcohol the damage in the brain would progress.”
Although the harmful effects of alcohol on the brain are widely known, the structural changes observed are very varied.
In addition, diagnostic markers are lacking to characterise brain damage induced by alcohol, especially at the beginning of abstinence.
This is a critical period due to the high rate of relapse that it presents, said the researchers.
The study published in JAMA Psychiatry is the first to show damage in the brain continues during the first weeks of abstinence – even though the consumption of alcohol ceases.
The participants whose average age was 46 had been hospitalised because of an alcohol use disorder.
Their brain scans were compared with a control group of 36 men without alcohol problems with an average age of 41.
Dr Canals said: “An important aspect of the work is the group of patients participating in our research are hospitalised in a detoxification program.
“Their consumption of addictive substances is controlled, which guarantees that they are not drinking any alcohol. Therefore, the abstinence phase can be followed closely.”
Another differential characteristic of this study is that it has been carried out in parallel in a model with Marchigian Sardinian
At the same time his team also carried out experiments on rats with a preference for alcohol.
This allowed them to monitor the transition from normal to alcohol dependence in the brain – a process “not possible to see in humans”, explained first author Dr Silvia De Santis.
The damage observed during the period of abstinence affect mainly the right hemisphere and the frontal area of the brain.
This rejects the conventional idea the microstructural alterations begin to revert to normal immediately after abandoning the consumption of alcohol.
Dr Canals said drinking causes “a generalised change in the white matter, that is, in the set of fibres that communicate different parts of the brain.”
He said:”The alterations are more intense in the corpus callosum and the fimbria. The corpus callosum is related to the communication between both hemispheres.
“The fimbria contains the nerve fibres that communicate the hippocampus, a fundamental structure for the formation of memories, the nucleus accumbens and the prefrontal cortex.”
The nucleus accumbens is part of the reward system of the brain and the prefrontal cortex is fundamental in decision making.
The researchers are now planning to characterise the inflammatory and degenerative processes independently and more precisely.
They hope this will shed light on the progression during the early abstinence phase in people with alcohol abuse problems.
Recent British research has found drinking even moderate amounts of alcohol is linked to changes in brain structure and an increased risk of worsening mental function.
The 30-year study looked at the brains of 550 middle-aged heavy and moderate drinkers – and teetotallers.
The Oxford University and University College London team found people drank more alcohol had a greater risk of hippocampal atrophy – a form of brain damage that affects memory and spatial navigation.
People who drank more than 30 units a week on average had the highest risk, but even those who drank moderately – between 14 and 21 units a week – were far more likely than abstainers to have hippocampal atrophy, the scientists said.
They said their results supported a recent lowering of drinking limit guidelines in Britain, but posed questions about limits recommended in the United States.