Repeated alcohol detoxifications can impair cognitive function
- Patients undergoing alcohol detoxification are more likely to have seizures if they have had previous episodes of detoxification.
- New research confirms that repeated detoxifications can also impair cognitive function through damage to the frontal lobes.
- Patients with mild to moderate alcoholism who have had two or more withdrawals performed worse on maze, vigilance and delay tasks.
Researchers and clinicians know that patients undergoing alcohol detoxification are more likely to experience seizures if they have undergone previous episodes of detoxification. Prior research has also indicated that multiple withdrawals may lead to changes in brain functioning. A study in the October issue of Alcoholism: Clinical & Experimental Research confirms previous findings of neurocognitive changes in alcoholics, extends those findings to individuals with mild to moderate alcoholism, and demonstrates a relationship of those changes to multiple withdrawals.
"Results from this study support previous findings of impaired frontal-lobe function in alcoholics," said Theodora Duka, associate professor at the University of Sussex and first author of the study. "Our study adds to that by showing that such impairments can be found also in non-severe alcoholics. But its major contribution to the field is that the number of detoxifications that patients experience contributes significantly to these impairments."
"Some clinicians tend to ignore the issue of multiple withdrawals, whereas other clinicians feel they’re important, having come to realize that patients who have had multiple withdrawals are much more likely to have more severe withdrawal subsequently, and probably not respond as well to medication to block the withdrawal symptoms," said Robert Malcolm, professor of psychiatry, family medicine and pediatrics, and clinical investigator at the Center for Drug and Alcohol Programs, Medical University of South Carolina. "This study squarely points out the relevance of multiple withdrawals by demonstrating some alterations in neurocognitive functioning in this group of people."
Study authors examined 85 volunteers divided into two groups: 42 abstinent alcoholics (24 males, 18 females) in inpatient treatment, and 43 social drinkers (23 males, 20 females) recruited from a university setting. The patient population was further divided into two populations based on information about prior, medically supervised detoxifications: patients with fewer than two experiences (n=36) and patients with two or more experiences (n=6). All of the subjects were asked to complete four types of tasks designed to measure executive function, which is responsible for supervising the production and execution of responses based on demands from the environment. The four tasks included a maze, which measured the ability to follow goals; a color-naming task; a vigilance task, which measured the ability to pay attention and disinhibit a pre-potent response; and a delay task, which measured the ability to wait before a response in order to receive a reward.
Results indicate that repeated withdrawals from alcohol are associated with increased impairment of cognitive function, specifically, frontal-lobe damage.
"The frontal lobes are extremely important for inhibiting behaviors," said Malcolm, "and are also important for tasks that require attention."
The results show that patients with two or more previous, medically supervised detoxifications performed worse than patients with less than two or no withdrawal experiences in the maze, vigilance and delay tasks.
"Compared to social drinkers," said Duka, "the alcoholics were impaired in all the tasks except for the color-naming task. The age that patients started drinking, and the amount of alcohol they used to drink up to the last six months before treatment, appeared also to play a role. Only measures of the delay task, the ability to wait before a response in order to receive a reward, appeared to depend solely on the number of detoxifications."
What should be emphasized about these findings, added Malcolm, is that they pertain to "mild to moderate alcoholics, not severe alcoholics. These were generally functioning people who, if they were seen in a clinician’s office, would not appear to be cognitively impaired, but yet they are." Identification of the mild to moderate classifications of alcoholism was determined through questionnaires about alcohol use, severity of dependence, and expectations from alcohol.
"Another interesting finding of Dr. Duka’s is an association between multiple withdrawals and higher levels of nicotine or cigarette smoking," said Malcolm, "which I think is a fascinating phenomenon and needs to be followed up on."
Duka said her findings have implications not only for individuals who have experienced multiple withdrawals from alcohol, but also the clinician who treats them. "These individuals might be more difficult to treat," she said. "When they are being helped to detoxify from alcohol, they may need extra support to prevent them from relapsing. It might even be sensible to wait a while before starting detox, if it helps to get the post-detox support organized."
’The truth of the matter," said Malcolm, "is that researchers really know very little about the effects of multiple withdrawals on cognitive function. This paper points out the relevance of clinicians asking patients about past withdrawals, the number of them, and how severe they were. Hopefully, it may influence clinicians to do further cognitive testing in order to get a sense of their patients’ capabilities for rehabilitation and present and future functioning. In other words, these findings represent a clue that some patients who have had multiple withdrawals might be impaired and might have trouble with their work and in their personal lives because of their impaired thinking processes."
Alcoholism: Clinical & Experimental Research (ACER) is the official journal of the Research Society on Alcoholism and the International Society for Biomedical Research on Alcoholism. Co-authors of the ACER paper included: Julia M Townshend and David N. Stephens of the Laboratory of Experimental Psychology at the University of Sussex; and Kirsty Collier of Westminster Health Care at Farm Place in Ockley, Dorking. The study was funded by the UK Medical Research Council Program.
Theodora Duka | EurekAlert!
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