Measuring episodic verbal learning ability in alcohol-related cognitive disorders in relation to everyday functioning

Abstract

Adequate and timely assessment of learning abilities in individuals with alcohol-related cognitive disorders is highly relevant to optimize addiction care. Learning curves of episodic verbal memory tests have been used to assess learning ability in various neurocognitive disorders, but studies in alcohol-related cognitive disorders are lacking. Therefore, this study investigated California Verbal Learning Test (CVLT) learning curves in individuals with alcohol-use disorder (AUD) with and without cognitive impairments and examined associations between learning curves and changes in everyday functioning following a multicomponent care program. We fitted learning curves over the five immediate recall trials of the Dutch version of the CVLT of patients with Korsakoff's syndrome (KS; N = 117), alcohol-related cognitive impairment no KS (ARCI; N = 147), and uncomplicated AUD (N = 43) using a generalized non-linear mixed regression. This model was based on three different parameters: initial memory performance (attention), maximum number of correctly recalled words (maximum learning), and the increase of correctly recalled words over the trials (learning rate). Next, we related these learning curves with ratings of everyday activities using the Patient Competency Rating Scale (PCRS) before and after a care program following admission. Modelled learning curves differed across groups, with significant differences in Attention (KS<ARCI<AUD, p < 0.001), Maximum Learning (KS<ARCI<AUD, p<0.001), and Learning Rate (KS<ARCI=AUD, p < 0.001). However, modelled learning curves were not related to reliable improvement in PCRS scores (p>0.05). Although modelled learning curves may be used to differentiate diagnostic groups in alcohol-related cognitive disorders, future studies are needed to establish the criterion validity of learning curves in this population.