Carolien Zeetsen

79 CHAPTER Cognitive performance during addiction treatment 5 Introduction About 30% – 80% of the people seeking treatment for alcohol use disorder (AUD) have cognitive impairments (Copersino et al., 2009; Bruijnen, Dijkstra, et al., 2019). In patients with Korsakoff’s syndrome (KS) cognitive impairments are severe and a hallmark of the disorder. KS in chronic alcoholics is caused by thiamine deficiency, which is an indirect effect of the chronic alcohol use (Arts et al., 2017). Its symptoms include severe memory deficits, confabulations, apathy, disorders of affect, social–cognitive problems and impaired insight into the illness (Arts et al., 2017; Rensen et al., 2017). However, most patients with alcohol– related cognitive impairments (ARCI; Heirene et al., 2018) do not fulfil the criteria for KS, as they have less severe cognitive deficits, which are often overlooked and underdiagnosed by clinicians. ARCI may be the result of indirect effects of alcohol use, such as liver cirrhosis or cerebrovascular risk factors, but may also be caused by direct effects of long–term alcohol abuse in individuals who are not (or not long) abstinent from alcohol, like the toxic actions of alcohol itself or the consequences of alcohol withdrawal. Acute alcohol intoxication primarily acts upon executive functions such as planning, verbal fluency, memory and complex motor control (Peterson et al., 1990; Lyvers et al., 2010). However, both residual and chronic symptoms of alcohol intoxication are diffuse and found in all cognitive domains (Stavro et al., 2013). Patients with ARCI themselves do not always report subjective complaints because these may be obscured by the addiction itself, or because of a lack of insight into their own cognitive deficits (Walvoort et al., 2016). In general, the absence of subjective experiences of cognitive deficits is a poor predictor of cognitive performance on objective measures (Horner et al., 1999). In order to detect cognitive impairments in individuals with AUD, cognitive screens can be used that quantify cognitive performance. A relatively short and easy to administer screener is the Montreal Cognitive Assessment (MoCA; Nasreddine et al., 2005). The MoCA is often used for the detection of ARCI at an early stage of addiction treatment (Bruijnen, Jansen, et al., 2019) and is being implemented in addiction care more and more (Copersino et al., 2009; Alarcon et al., 2015; Ewert et al., 2018; Ridley et al., 2018). Oudman et al. (2014) found the MoCA to be superior to the Mini–Mental State Examination (Folstein et al., 1975) in distinguishing patients with KS from controls. The availability of three alternate forms of the MoCA makes it possible to retest individuals over time (Chertkow et al., 2011) and thus follow the course of cognitive functioning during treatment. All three versions are found to be largely equivalent and the MoCA total score is a reliable measure for screening cognitive performance (Bruijnen et al., 2020).