Carolien Zeetsen

81 CHAPTER Cognitive performance during addiction treatment 5 Methods Design A multiple time–series design was used, in which the MoCA was administered at three time points of assessment during clinical treatment. The first administration took place at intake or clinical admission (T0). The second administration followed after approximately six weeks of admission (T1). The third and final administration was right before clinical discharge (T2). Data were collected between May 2010 and May 2019 and supplemented from an existing clinical research database. The study was approved by the internal review board of Vincent van Gogh Institute for Psychiatry and all patients provided informed consent in accordance with the Dutch General Data Protection Regulation and the declaration of Helsinki. Participants All participants were inpatients of the Centre of Excellence for Korsakoff and Alcohol– Related Cognitive Impairments of Vincent van Gogh Institute for Psychiatry in Venray, the Netherlands. They were referred to the clinic with suspected cognitive impairments related to long–term alcohol use. The patients were diagnosed by a multidisciplinary team in the first 10 to 12 weeks of admission, based on an extensive neuropsychological assessment that was administered after a minimum of six weeks abstinence (Walvoort et al., 2013), a neurological and psychiatric examination, observations from therapists and (psychiatric) nurses, physical exams, and neuroradiological examination (MRI). Note that the MoCA was not used in this diagnostic process. Three patient groups were included in the study, all of whom fulfilled the DSM–5 criteria for AUD, with two groups also fulfilling the DSM–5 criteria for mild and major substance– induced (alcohol) neurocognitive disorder (NCD; APA, 2013). The first group was diagnosed with AUD (not fulfilling the criteria for NCD), the second group with ARCI (fulfilling the criteria for mild NCD) and the third group with KS (fulfilling the criteria for major NCD). The latter group also fulfilled the clinical criteria of KS described by Kopelman (2002) and Arts et al. (2017). These include 1) the presence of a persistent memory impairment resulting in severe deficits in social functioning, 2) the absence of delirium or dementia due to a neurodegenerative disease, 3) evidence for a history of Wernicke encephalopathy, 4) confabulatory behaviour, and 5) a history of malnutrition or thiamine deficiency. None of the patients had any evidence of brain abnormalities that could account for their condition apart from atrophy or white–matter lesions associated with chronic alcohol use (Arts et al., 2017), and none of the patients fulfilled the proposed criteria for alcohol–related dementia (Oslin et al., 1998). Finally, none of the included patients had hearing problems, language or communication deficits, or visual deficits that made MoCA administration impossible.