Brief screening for cognitive impairment in addictive disorders

Chronic use of mind altering substances can lead to a wide variety of neuropsychological deficits, affecting the domains of attention, learning, memory, reasoning. Executive functions such as working memory, cognitive flexibility and inhibitory control may specifically be impaired. These deficits can impact engagement in effective psychosocial interventions. Mild to moderate cognitive dysfunction may not be picked up in routine clinical examination or through commonly used tests like the mini-mental state examination (MMSE). Detailed neuropsychological tests, although extremely valuable, are time and human-resource intensive and are not readily available to the clinician. This study attempted to devise a brief cognitive screen (BCS- AUD) for alcohol use disorders. Ninety subjects who fulfilled ICD-10 criteria for alcohol use disorders were assessed on the MMSE and selective tests from the NIMHANS neuropsychological battery. While 79 (87.78%) of patients had adequate scores on the MMSE (>25), cognitive deficits were noted with relatively high frequency on finger tapping (92.22-93.33%), auditory verbal learning test delayed recall AVLTDR (37-63%) and Tower of London 5 move subtest (42%). Statistically significant associations were found between MMSE and Digit symbol total time (0.05), Finger tapping right hand (0.01), Tower of London total number of problems solved with minimum moves (TNPSMM) (0.05), Verbal working memory two back hits (VM2BKHIT) (0.01), AVLTDR (0.01), and complex figure test-copy (0.01). Principal component analysis helped to identify three tests that merited inclusion in the BCS-AUD, namely Finger Tapping Test, Verbal Working Memory N Back Test and Auditory Verbal Test (AVLT). The utility of the BCS-AUD in identifying cognitive dysfunction in other substance use disorders needs to be examined. Patients rating positive on the cognitive screener would require in-depth evaluation, monitoring and remediation.