[Cognitive impairments in alcohol dependence: From screening to treatment improvements]. / Troubles cognitifs dans l'alcoolodépendance : intérêt du dépistage dans l'optimisation des prises en charge.

Alcohol-related cognitive impairments are largely underestimated in clinical practice, even though they could limit the benefit of alcohol treatment and hamper the patient's ability to remain abstinent or to respect his/her therapeutic contract. These neuropsychological deficits can impact the management of patients well before the development of the well-known Korsakoff's syndrome. Indeed, even in the absence of ostensible neurological complications, excessive and chronic alcohol consumption results in damage of brain structure and function. The frontocerebellar circuit and the circuit of Papez, respectively involved in motor and executive abilities and episodic memory, are mainly affected. Those brain dysfunctions are associated with neuropsychological deficits, including deficits of executive functions, episodic memory, social cognition, as well as visuospatial and motor abilities. Such cognitive disorders can interfere with the motivation process to abandon maladjusted drinking behavior in favor of a healthier lifestyle (such as abstinence or controlled alcohol consumption). They can also limit the patient's capacity to fully benefit from treatment (notably psychoeducation and cognitive-behavioural treatments) currently widely proposed in French Addiction departments. In addition, they may contribute to relapse which is multi-determinated. A neuropsychological assessment appears therefore crucial to take relevant clinical decisions. However, very few addiction departments have the human and financial resources to conduct an extensive neuropsychological examination of all patients with alcohol dependence. Some brief screening tools can be used, notably the MOntreal Cognitive Assessment and the Brief Evaluation of Alcohol-Related Neuropsychological Impairments, which has been especially designed to assess cognitive and motor deficits in alcoholism. These tools can be used by non-psychologist clinicians to detect alcohol-related cognitive deficits, which require an extensive cognitive examination conducted by a neuropsychologist. The presence of cognitive dysfunctions in patients early in abstinence should encourage clinicians to adjust the modalities of the treatment. The fact to favor recovery of cognitive functions and brain volumes with abstinence or drastic reduction of alcohol consumption could be a first way to make it possible for patients to be cognitively able to benefit from treatment. Further studies are required to determine whether specifically designed cognitive remediation could boost (accelerate or increase) the recovery of brain functioning. Additionally, a potential effect of thiamine to limit alcohol-related cognitive deficits before the development of neurological complications remains to be determined. In this review, we presented the pattern of structural brain damage and the associated cognitive and motor impairments in alcohol-dependent patients. We then emphasized the harmful effects of neuropsychological deficits in the management of these patients. We also pointed how relevant it is to screen patients with neuropsychological impairments and we focused on the presentation of two brief screening tools for cognitive impairments, especially designed for alcohol-related deficits or not. Finally, we reported how these neuropsychological impairments could be taken into consideration the treatment of alcohol addiction by adjusting its timing and modalities.

Impaired decision-making and brain shrinkage in alcoholism.

Alcohol-dependent individuals usually favor instant gratification of alcohol use and ignore its long-term negative consequences, reflecting impaired decision-making. According to the somatic marker hypothesis, decision-making abilities are subtended by an extended brain network. As chronic alcohol consumption is known to be associated with brain shrinkage in this network, the present study investigated relationships between brain shrinkage and decision-making impairments in alcohol-dependent individuals early in abstinence using voxel-based morphometry. Thirty patients performed the Iowa Gambling Task and underwent a magnetic resonance imaging investigation (1.5T). Decision-making performances and brain data were compared with those of age-matched healthy controls. In the alcoholic group, a multiple regression analysis was conducted with two predictors (gray matter [GM] volume and decision-making measure) and two covariates (number of withdrawals and duration of alcoholism). Compared with controls, alcoholics had impaired decision-making and widespread reduced gray matter volume, especially in regions involved in decision-making. The regression analysis revealed links between high GM volume in the ventromedial prefrontal cortex, dorsal anterior cingulate cortex and right hippocampal formation, and high decision-making scores (P<0.001, uncorrected). Decision-making deficits in alcoholism may result from impairment of both emotional and cognitive networks.