The Course of Cognitive Performance during Inpatient Treatment in Patients with Alcohol Use Disorder with No, Mild or Major Neurocognitive Disorders.

AIMS: In patients with a history of chronic alcohol abuse, neurocognitive disorders (NCD) are not uncommon. The current study aimed to explore the course of cognitive performance, as measured by the Montreal Cognitive Assessment (MoCA), and everyday cognitive functioning, as measured by the Patient Competency Rating Scale (PCRS), in a large group of patients with alcohol use disorder (AUD) admitted to the Center of Excellence for Korsakov and Alcohol-related Cognitive Impairments. METHODS: A multiple time-series design was used, in which the MoCA was administered at three time points of assessment, and the PCRS was completed by both the patient and a clinician at two time points, all during clinical treatment. RESULTS: A total of 524 patients were included, 71 of whom were diagnosed with AUD only, 284 with AUD and mild NCD (ARCI) and 169 with AUD, major NCD and fulfilling criteria for Korsakoff's syndrome (KS). CONCLUSIONS: Cognitive performance improved for all three groups during treatment, sustained abstinence and recovery from AUD. A low memory performance on the MoCA without improvement over time was predictive for KS, while improvement on this domain did not differentiate between AUD and ARCI. Changes in overall cognitive performance and orientation in patients with KS were positively related to changes in everyday cognitive functioning.

Characterization of motor function in mice developmentally exposed to ethanol using the Catwalk system: Comparison with the triple horizontal bar and rotarod tests.

Studies with human subjects indicate that ethanol exposure during fetal development causes long-lasting alterations in motor coordination that are, in part, a consequence of cerebellar damage. Studies with rats exposed to ethanol during the neonatal brain growth spurt have consistently recapitulated these deficits. However, studies with mice have yielded mixed results. We hypothesized that the use of highly sensitive motor function tests, such as the Catwalk test, would reliably detect motor function deficits in mice developmentally exposed to ethanol. Venus-vesicular GABA transporter transgenic mice were ethanol exposed during postnatal days 4-9 using vapor inhalation chambers and then subjected to the Catwalk test during adolescence. Catwalk data were rigorously analyzed using an innovative multistep statistical approach. For comparison, motor coordination and strength were assessed with the triple horizontal bar and rotarod tests. Unexpectedly, we found that out of 186 parameters analyzed in the Catwalk test, only one was affected by ethanol exposure (i.e., reduced coupling between left front paw and the right hind paw). In the triple horizontal bar test, ethanol-exposed mice were able to hold to the bars for less time than controls. Surprisingly, ethanol-exposed mice performed better in the rotarod test than controls. These data indicate that neonatal ethanol exposure of mice causes mixed effects on motor function during adolescence. The Catwalk test suggests that gait is generally preserved in these mice, whereas the triple horizontal bar test revealed deficits on motor strength and the rotarod test an increase in motor coordination.

Chronic Neurologic Effects of Alcohol.

Chronic alcohol use induces silent changes in the structure and function of the central and peripheral nervous systems that eventually result in irreversible, debilitating repercussions. Once identified, nutritional supplementation and cessation measures are critical in preventing further neurologic damage. The proposed mechanisms of neuronal injury in chronic alcohol abuse include direct toxic effects of alcohol and indirect effects, including those resulting from hepatic dysfunction, nutritional deficiencies, and neuroinflammation. Clinical manifestations include cerebellar ataxia, peripheral neuropathy and Wernicke-Korsakoff encephalopathy. Continued exploration of the pathophysiologic mechanisms may lead to the discovery of early interventions that can prevent permanent neurologic injury.

Rosmarinic acid protects against chronic ethanol-induced learning and memory deficits in rats.

OBJECTIVES: Ethanol consumption induces neurological disorders including cognitive dysfunction. Oxidative damage is considered a likely cause of cognitive deficits. We aimed to investigate the effects of rosmarinic acid (RA) in different doses for 30 days on chronic ethanol-induced cognitive dysfunction using the passive avoidance learning (PAL) and memory task in comparison with donepezil, a reference drug. We also evaluated the levels of superoxide dismutase (SOD), catalase (CAT), and lipid peroxidation in hippocampus as possible mechanisms. METHODS: Memory impairment was induced by 15% w/v ethanol (2 g/kg, i.g.) administration for 30 days. RA (8, 16, and 32 mg/kg, i.g.) or donepezil (2 mg/kg, i.g.) was administered 30 minutes before ethanol. The acquisition trial was done 1 hour after the last administration of RA and donepezil. At the end, animals were weighed and hippocami were isolated for analyzing of oxidant/antioxidant markers. RESULTS: Ethanol caused cognition deficits in the PAL and memory task. While RA 16 and 32 mg/kg improved cognition in control rats, it prevented learning and memory deficits of alcoholic groups. RA 8 mg/kg did not influence cognitive function in both control and alcoholic rats. RA 32 mg/kg had comparable effects with donepezil in prevention of acquisition and retention memory impairment. The higher doses of RA not only prevented increased lipid peroxidation and nitrite content but also decreased SOD, CAT, GSH, and FRAP levels in alcoholic groups and exerted antioxidant effects in non-alcoholic rats. DISCUSSION: We showed that RA administration dose-dependently prevented cognitive impairment induced by chronic ethanol in PAL and memory and disturbed oxidant/antioxidant status as a possible mechanism. The antioxidant, anticholinesterase, and neuroprotective properties of RA may be involved in the observed effects. Therefore, RA represents a potential therapeutic option against chronic ethanol-induced amnesia which deserves consideration and further examination.

Neurobiology of comorbid post-traumatic stress disorder and alcohol-use disorder.

Post-traumatic stress disorder (PTSD) and alcohol-use disorder (AUD) are highly comorbid in humans. Although we have some understanding of the structural and functional brain changes that define each of these disorders, and how those changes contribute to the behavioral symptoms that define them, little is known about the neurobiology of comorbid PTSD and AUD, which may be due in part to a scarcity of adequate animal models for examining this research question. The goal of this review is to summarize the current state-of-the-science on comorbid PTSD and AUD. We summarize epidemiological data documenting the prevalence of this comorbidity, review what is known about the potential neurobiological basis for the frequent co-occurrence of PTSD and AUD and discuss successes and failures of past and current treatment strategies. We also review animal models that aim to examine comorbid PTSD and AUD, highlighting where the models parallel the human condition, and we discuss the strengths and weaknesses of each model. We conclude by discussing key gaps in our knowledge and strategies for addressing them: in particular, we (1) highlight the need for better animal models of the comorbid condition and better clinical trial design, (2) emphasize the need for examination of subpopulation effects and individual differences and (3) urge cross-talk between basic and clinical researchers that is reflected in collaborative work with forward and reverse translational impact.

Cognitive Decline and Recovery in Alcohol Abuse.

Alcohol consumption triggers a neuroinflammatory response which, if prolonged, can lead to substantial volume loss in both gray and white matter. This brain injury is associated with characteristic cognitive deficits, and, in extreme cases, with dementia. Even mild cognitive impairment creates a significant hurdle for alcohol rehabilitation, because the domains that are affected tend to be those important for sustaining abstinence. Thus, cognitive decline induced by alcohol contributes to the persistence of alcoholism. Here, I present converging data from animal and clinical studies that show how alcohol affects the brain and behavior. Although there is currently no targeted treatment for overcoming alcohol-induced cognitive decline, emerging evidence suggests that physical activity is both protective and restorative. This is a potential avenue for future programs targeted at treating alcohol abuse.

Propofol for Treatment of Refractory Alcohol Withdrawal Syndrome: A Review of the Literature.

The authors evaluated all available evidence on the use of propofol as an adjuvant for the treatment of resistant alcohol withdrawal syndrome (AWS) in comparison to other therapies. A comprehensive PubMed search (1966-December 2015) was conducted using the search terms propofol, alcohol withdrawal, and drug therapy. Articles were cross-referenced for other citations. Clinical studies, case series, and case reports published in the English language assessing the use of propofol in adult patients for treatment of AWS were reviewed for inclusion. Propofol is a sedative-hypnotic that exerts its actions through agonism of GABAA receptors at a different binding site than benzodiazepines and reduces glutamatergic activity through N-methyl-d-aspartase (NMDA) receptor blockade. Dosages from 5 to 100 µg/kg/minute reduced AWS symptoms with frequent development of hypotension and requirement for mechanical ventilation. Patients on propofol often experienced longer durations of mechanical ventilation and length of stay, which may be attributed to more-resistant cases of AWS. When propofol was compared with dexmedetomidine as adjuncts in AWS, both agents showed similar benzodiazepine- and haloperidol-sparing effects. Dexmedetomidine was associated with more numerical rates of bradycardia, while propofol was associated with more numerical instances of hypotension. Dexmedetomidine was used more frequently in nonintubated patients. The available data assessing the utility of propofol for AWS exhibited significant heterogeneity. Propofol may be useful in a specific population of patients with AWS, limited to those who are not clinically responding to first-line therapy with benzodiazepines. Specifically, propofol should be considered in patients who are refractory to or not candidates for other adjuvant therapies, patients already requiring mechanical ventilation, or those with seizure activity or refractory delirium tremens. In severe, refractory AWS, adjuvant therapy with propofol may be considered but requires further research to recommend its use either preferentially or as monotherapy.

Supersensitive Kappa Opioid Receptors Promotes Ethanol Withdrawal-Related Behaviors and Reduce Dopamine Signaling in the Nucleus Accumbens.

BACKGROUND: Chronic ethanol exposure reduces dopamine transmission in the nucleus accumbens, which may contribute to the negative affective symptoms associated with ethanol withdrawal. Kappa opioid receptors have been implicated in withdrawal-induced excessive drinking and anxiety-like behaviors and are known to inhibit dopamine release in the nucleus accumbens. The effects of chronic ethanol exposure on kappa opioid receptor-mediated changes in dopamine transmission at the level of the dopamine terminal and withdrawal-related behaviors were examined. METHODS: Five weeks of chronic intermittent ethanol exposure in male C57BL/6 mice were used to examine the role of kappa opioid receptors in chronic ethanol-induced increases in ethanol intake and marble burying, a measure of anxiety/compulsive-like behavior. Drinking and marble burying were evaluated before and after chronic intermittent ethanol exposure, with and without kappa opioid receptor blockade by nor-binaltorphimine (10mg/kg i.p.). Functional alterations in kappa opioid receptors were assessed using fast scan cyclic voltammetry in brain slices containing the nucleus accumbens. RESULTS: Chronic intermittent ethanol-exposed mice showed increased ethanol drinking and marble burying compared with controls, which was attenuated with kappa opioid receptor blockade. Chronic intermittent ethanol-induced increases in behavior were replicated with kappa opioid receptor activation in naïve mice. Fast scan cyclic voltammetry revealed that chronic intermittent ethanol reduced accumbal dopamine release and increased uptake rates, promoting a hypodopaminergic state of this region. Kappa opioid receptor activation with U50,488H concentration-dependently decreased dopamine release in both groups; however, this effect was greater in chronic intermittent ethanol-treated mice, indicating kappa opioid receptor supersensitivity in this group. CONCLUSIONS: These data suggest that the chronic intermittent ethanol-induced increase in ethanol intake and anxiety/compulsive-like behaviors may be driven by greater kappa opioid receptor sensitivity and a hypodopaminergic state of the nucleus accumbens.

Protective Effects of Tetramethylpyrazine on Cerebrovascular Regulations in Rats with Chronic Alcoholic Encephalopathy.

Recent studies showed that pathology of alcoholic encephalopathy was associated with cerebral vascular damage. TMP (tetramethyl- pyrazine) is widely used in the treatment of cerebrovascular diseases, however, it has not been reported whether TMP can relieve alcohol-induced cerebral vascular damages. The study was performed to investigate the learning and memory, cerebrovascular pathological changes and the expressions of vascular endothelial growth factor (VEGF) and serum levelsofendothelin-1 (ET-1) in the rat model of chronic alcoholic encephalopathy, and explore the effects of TMP intervention on alcoholic encephalopathy. In the present study, the rat model of chronic alcoholic encephalopathy was established by the gavage administration of alcohol; the learning and memory ability was tested by Morris water maze; the expression of VEGF was measured by RT-PCR and Western blot; and the serum levels of ET-1 was measured by radioimmunoassay. We found that alcohol intoxication impaired learning and memory, induced VEGF overexpression and increased ET 1 concentrations. TMP intervention improved learning abilities, increased the VEGF expression and reduced ET-1 level. These results indicate that TMP exhibits therapeutic effects on chronic alcoholic encephalopathy.

A review on alcohol: from the central action mechanism to chemical dependency.

INTRODUCTION: alcohol is a psychotropic depressant of the central nervous system (CNS) that promotes simultaneous changes in several neuronal pathways, exerting a profound neurological impact that leads to various behavioral and biological alterations. OBJECTIVES: to describe the effects of alcohol on the CNS, identifying the signaling pathways that are modified and the biological effects resulting from its consumption. METHODS: a literature review was conducted and articles published in different languages over the last 15 years were retrieved. RESULTS: the studies reviewed describe the direct effect of alcohol on several neurotransmitter receptors (gamma-aminobutyric acid [GABA], glutamate, endocannabinoids AEA and 2-AG, among others), the indirect effect of alcohol on the limbic and opioid systems, and the effect on calcium and potassium channels and on proteins regulated by GABA in the hippocampus. DISCUSSION AND CONCLUSION: the multiple actions of alcohol on the CNS result in a general effect of psychomotor depression, difficulties in information storage and logical reasoning and motor incoordination, in addition to stimulating the reward system, a fact that may explain the development of addiction. Knowledge on the neuronal signaling pathways that are altered by alcohol allows the identification of effectors which could reduce its central action, thus, offering new therapeutic perspectives for the rehabilitation of alcohol addicts.

A review on alcohol: from the central action mechanism to chemical dependency / Uma revisão sobre o álcool: do mecanismo de ação central à dependência química

SummaryIntroduction:alcohol is a psychotropic depressant of the central nervous system (CNS) that promotes simultaneous changes in several neuronal pathways, exerting a profound neurological impact that leads to various behavioral and biological alterations.Objectives:to describe the effects of alcohol on the CNS, identifying the signaling pathways that are modified and the biological effects resulting from its consumption.Methods:a literature review was conducted and articles published in different languages over the last 15 years were retrieved.Results:the studies reviewed describe the direct effect of alcohol on several neurotransmitter receptors (gamma-aminobutyric acid [GABA], glutamate, endocannabinoids AEA and 2-AG, among others), the indirect effect of alcohol on the limbic and opioid systems, and the effect on calcium and potassium channels and on proteins regulated by GABA in the hippocampus.Discussion and conclusion:the multiple actions of alcohol on the CNS result in a general effect of psychomotor depression, difficulties in information storage and logical reasoning and motor incoordination, in addition to stimulating the reward system, a fact that may explain the development of addiction. Knowledge on the neuronal signaling pathways that are altered by alcohol allows the identification of effectors which could reduce its central action, thus, offering new therapeutic perspectives for the rehabilitation of alcohol addicts.

ResumoIntrodução:o álcool é uma substância psicotrópica depressora do sistema nervoso central (SNC), que promove alteração simultânea de inúmeras vias neuronais, gerando profundo impacto neurológico e traduzindo-se em diversas alterações biológicas e comportamentais.Objetivos:descrever as ações do álcool sobre o SNC, identificando as vias de sinalização modificadas e os efeitos biológicos gerados pelo seu consumo.Métodos:revisão bibliográfica, priorizando trabalhos multilinguísticos publicados nos últimos 15 anos.Resultados:são descritas ação direta do álcool em inúmeros receptores de neurotransmissores (ácido gama-aminobutírico – GABA, glutamato, endocanabinoides AEA e 2-AG, entre outros), ação indireta do álcool no sistema límbico e opioide, ação sobre canais de cálcio, potássio e proteínas reguladas por GABA no hipocampo, além de ações centrais mediadas pela deficiência de vitamina B1.Conclusão:a ação multifocal do álcool sobre o SNC resulta em efeito geral de depressão psicomotora, dificuldades no armazenamento de informações e no raciocínio lógico, incoordenação motora, além da estimulação do sistema de recompensa, o que pode explicar o desenvolvimento da dependência química. O conhecimento das vias de sinalização neuronais alteradas pelo álcool permite reconhecer a descrição de efetores que possam reduzir sua ação central e, assim, vislumbrar novas perspectivas terapêuticas para a reabilitação de adictos a essa substância.

A quantitative evaluation of alcohol withdrawal tremors.

This paper evaluates the relation between Alcohol Withdrawal Syndrome tremors in the left and right hands of patients. By analyzing 122 recordings from 61 patients in emergency departments, we found a weak relationship between the left and right hand tremor frequencies (correlation coefficient of 0.63). We found a much stronger relationship between the expert physician tremor ratings (on CIWA-Ar 0-7 scale) of the two hands, with a correlation coefficient of 0.923. Next, using a smartphone to collect the tremor data and using a previously developed model for obtaining estimated tremor ratings, we also found a strong correlation (correlation coefficient of 0.852) between the estimates of each hand. Finally, we evaluated different methods of combining the data from the two hands for obtaining a single tremor rating estimate, and found that simply averaging the tremor ratings of the two hands results in the lowest tremor estimate error (an RMSE of 0.977). Looking at the frequency dependence of this error, we found that higher frequency tremors had a much lower estimation error (an RMSE of 1.102 for tremors with frequencies in the 3-6Hz range as compared to 0.625 for tremors with frequencies in the 7-10Hz range).

Moderating effect of working memory capacity on acute alcohol effects on BOLD response during inhibition and error monitoring in male heavy drinkers.

RATIONALE: While alcohol intoxication is known to increase disinhibited behavior, the degree to which disinhibition occurs appears to depend on a number of factors including executive functioning ability. However, the neural mechanisms by which individual differences in executive functioning lead to variable degrees of disinhibition remain unclear. OBJECTIVES: The aim of the current study was to examine the neural mechanisms by which individual differences in working memory (WM) capacity moderate alcohol-induced disinhibition. METHODS: Seventeen heavy-drinking males participated in a within-subjects design in which two sessions were completed: an alcohol session (.82 g/kg) and a control session. Participants completed a go/no-go task while undergoing functional magnetic resonance imaging (fMRI) after ingestion of the control or alcohol beverage. WM capacity was measured using an operation span task. RESULTS: Significant interactions of session and WM capacity emerged in contrasts examining successful response inhibition within superior temporal gyrus and unsuccessful inhibition in regions within the default mode network. In all cases, individuals with low WM capacity demonstrated a relative decrease in blood oxygen level-dependent (BOLD) response during the alcohol compared to control session, whereas the high-WM-capacity group demonstrated relative increases in BOLD response in the alcohol compared to control session. CONCLUSIONS: Low WM capacity appears to be associated with decreased neural response to signals indicating a need for behavioral control, an effect that may lead to increased difficulty with inhibiting responses and increased negative consequences from alcohol intoxication.

Human alcohol-related neuropathology.

Alcohol-related diseases of the nervous system are caused by excessive exposures to alcohol, with or without co-existing nutritional or vitamin deficiencies. Toxic and metabolic effects of alcohol (ethanol) vary with brain region, age/developmental stage, dose, and duration of exposures. In the mature brain, heavy chronic or binge alcohol exposures can cause severe debilitating diseases of the central and peripheral nervous systems, and skeletal muscle. Most commonly, long-standing heavy alcohol abuse leads to disproportionate loss of cerebral white matter and impairments in executive function. The cerebellum (especially the vermis), cortical-limbic circuits, skeletal muscle, and peripheral nerves are also important targets of chronic alcohol-related metabolic injury and degeneration. Although all cell types within the nervous system are vulnerable to the toxic, metabolic, and degenerative effects of alcohol, astrocytes, oligodendrocytes, and synaptic terminals are major targets, accounting for the white matter atrophy, neural inflammation and toxicity, and impairments in synaptogenesis. Besides chronic degenerative neuropathology, alcoholics are predisposed to develop severe potentially life-threatening acute or subacute symmetrical hemorrhagic injury in the diencephalon and brainstem due to thiamine deficiency, which exerts toxic/metabolic effects on glia, myelin, and the microvasculature. Alcohol also has devastating neurotoxic and teratogenic effects on the developing brain in association with fetal alcohol spectrum disorder/fetal alcohol syndrome. Alcohol impairs function of neurons and glia, disrupting a broad array of functions including neuronal survival, cell migration, and glial cell (astrocytes and oligodendrocytes) differentiation. Further progress is needed to better understand the pathophysiology of this exposure-related constellation of nervous system diseases and better correlate the underlying pathology with in vivo imaging and biochemical lesions.

Binge drinking in adolescents: a review of neurophysiological and neuroimaging research.

AIMS: While the relationship between chronic exposure to alcohol and neurobiological damage is well established, deleterious brain effects of binge drinking in youths have only recently been studied. METHODS: Narrative review of studies of brain disturbances associated with binge drinking as assessed by neuroimaging (EEG and IRMf techniques in particular) in adolescent drinkers. RESULTS: Some major points still deserved to be investigated; directions for future research are suggested. CONCLUSIONS: Information and prevention programs should emphasize that binge drinking is not just inoffensive social fun, but if carried on, may contribute to the onset of cerebral disturbances possibly leading to alcohol dependence later in life.

Time-frequency visualization of alcohol withdrawal tremors.

In this paper, we propose a signal processing method of assessing the severity tremors caused by alcohol withdrawal (AW) syndrome. We have developed an iOS application to calculate the Clinical Institute Withdrawal Assessment (CIWA) score which captures iPod movements using the built-in accelerometer in order to reliably estimate the tremor severity component of the score. We report on the characteristics of AW tremor, the accuracy of electronic assessment of tremor compared to expert clinician assessment, and the potential for using signal processing assessment to differentiate factitious from real tremor in patients seen in the emergency department, as well as in nurses mimicking a tremor. Our preliminary results are based on 84 recordings from 61 subjects (49 patients, 12 nurses). In general we found a linear relationship between energy measured by the accelerometer (in the 4.4-10 Hz range) and the expert rating of tremor severity. Additionally, we demonstrate that 75% of the recordings from patients with actual AW syndrome had a mean peak frequency higher than 7 Hz whereas only 17% of the nurses' factitious tremors were above 7 Hz, suggesting that tremor above 7 Hz could be a potential discriminator of real versus factitious tremors.

Sex differences in neuroadaptation to alcohol and withdrawal neurotoxicity.

Recent work suggests that sex differences exist with regard to both the nature of neuroadaptation to alcohol during the development of dependence, and possibly, the neurodegenerative consequences of alcohol dependence. Volumetric studies in human samples show that females may demonstrate increased volumetric brain loss with equal or lesser dependence histories than males. Furthermore, animal studies demonstrate sex differences in glutamatergic, GABAergic, and adenosinergic receptor signaling and endocrine responses following prolonged alcohol exposure. These differences may influence the development of dependence, neuronal function, and viability, particularly during alcohol withdrawal. The present review discusses the current state of knowledge in this regard. It is concluded that there exists a clear need for a more extensive examination of potential sex differences in neurodegenerative consequences of alcohol dependence in men and women, particularly with regard to the role that alterations in amino acid signaling and hypothalamic-pituitary-adrenal axis function may play. Furthermore, we note the need for expanded examination of the unique role that alcohol withdrawal-associated neuronal activity may have in the development of dependence-associated neurotoxicity.

Assessment of alcohol withdrawal in Native American patients utilizing the Clinical Institute Withdrawal Assessment of Alcohol Revised Scale.

BACKGROUND: The Clinical Institute Withdrawal Assessment of Alcohol Revised (CIWA-Ar) is a commonly used scale for assessing the severity of alcohol withdrawal syndrome in the acute setting. Despite validation of this scale in the general population, the effect of ethnicity on CIWA-Ar scoring does not appear in the literature. The purpose of our study was to investigate the validity of the CIWA-Ar scale among Native American patients evaluated for acute alcohol detoxification. METHODS: A case series of all patients seen for alcohol withdrawal at an Acute Drug and Alcohol Detoxification facility was conducted from June 1, 2011, until April 1, 2012. The CIWA-Ar scores were recorded by trained nursing staff on presentation to Triage Department and every 2 hours thereafter. At our institution, a score of 10 or greater indicates the need for inpatient hospital admission and treatment. Ethnicity was self-reported. Age, sex, blood alcohol concentration, blood pressure, and pulse were recorded on presentation and vital signs repeated every 2 hours. Patients were excluded from the study if other drug use was noted by history or initial urine drug screen. A multivariate logistic regression model was utilized to identify statistically significant variables associated with admission to the inpatient unit and treatment. The relationship of CIWA-Ar scores and ethnicity was compared using analysis of variance. RESULTS: A total of 115 whites, 45 Hispanics, and 47 Native Americans were included in the analysis. Native Americans had consistently lower CIWA-Ar scores at 0, 2, 4, and 6 hours than the other 2 ethnic groups (P = 0.002). In addition, Native Americans were admitted to the hospital less often than the other 2 groups for withdrawal (P < 0.001). CONCLUSIONS: The CIWA-Ar scale may underestimate the severity of alcohol withdrawal syndrome in certain ethnic group such as Native Americans. Further prospective studies should be undertaken to determine the validity of the CIWA-Ar scale in assessing alcohol withdrawal across different ethnic populations.