Neurological, nutritional and alcohol consumption factors underlie cognitive and motor deficits in chronic alcoholism. (15th December 2017)

• Record Type: Journal Article
• Authors: Fama, Rosemary; Le Berre, Anne‐Pascale; Hardcastle, Cheshire; Sassoon, Stephanie A.; Pfefferbaum, Adolf; Sullivan, Edith V.; Zahr, Natalie M.
• Is Part Of: Addiction biology. Volume 24:Number 2(2019)
• Page Start: 290
• Page End: 302
• Publication Date: 2017-12-15
• Subjects: alcohol -- ataxia -- Caine criteria -- memory -- thiamine -- Wernicke's encephalopathy; Substance abuse -- Periodicals; Substance abuse -- Physiological aspects -- Periodicals; Substance-Related Disorders -- periodicals; 616.86
• DOI: 10.1111/adb.12584
• Languages: English
• ISSNs: 1355-6215

Abstract

Abstract: Variations in pattern and extent of cognitive and motor impairment occur in alcoholism (ALC). Causes of such heterogeneity are elusive and inconsistently accounted for by demographic or alcohol consumption differences. We examined neurological and nutritional factors as possible contributors to heterogeneity in impairment. Participants with ALC ( n = 96) and a normal comparison group ( n = 41) were examined on six cognitive and motor domains. Signs of historically determined subclinical Wernicke's encephalopathy were detected using the Caine et al. criteria, which were based on postmortem examination and chart review of antemortem data of alcoholic cases with postmortem evidence for Wernicke's encephalopathy. Herein, four Caine criteria provided quantification of dietary deficiency, cerebellar dysfunction, low general cognitive functioning and oculomotor abnormalities in 86 of the 96 ALC participants. Subgroups based on Caine criteria yielded a graded effect, where those meeting more criteria exhibited greater impairment than those meeting no to fewer criteria. These results could not be accounted for by history of drug dependence. Multiple regression indicated that compromised performance on ataxia, indicative of cerebellar dysfunction, predicted non‐mnemonic and upper motor deficits, whereas low whole blood thiamine level, consistent with limbic circuit dysfunction, predicted mnemonic deficits. This double dissociation indicates biological markers that contribute to heterogeneity in expression of functional impairment in ALC. That non‐mnemonic and mnemonic deficits are subserved by the dissociable neural systems of frontocerebellar and limbic circuitry, both commonly disrupted in ALC, suggests neural mechanisms that can differentially affect selective functions, thereby contributing to heterogeneity in pattern and extent of dysfunction in ALC. Abstract : Dissociable alcohol, nutritional and neurological factors were predictive of selective cognitive and motor deficits in sober alcoholics. The study revealed a double dissociation: lower thiamine level and greater lifetime alcohol consumption selectively predicted episodic memory deficits, whereas ataxia selectively predicted executive function and upper motor deficits. This double dissociation identified biological markers that contribute to the heterogeneity in expression of functional impairment in alcoholism and highlights the importance of assessing occult Wernicke's encephalitis in individuals with alcohol use disorder.