Harmen Beurmanjer

67 Tapering GHB or BZDs for Detoxification in GHB-Dependent Patients 5 Participants ParticipantswerepatientswithGUDwho received an indication for inpatient detoxification. Patients were Included if they had 1) a diagnosis of GHB dependence according to the DSM-IV-TR, and 2) where aged >18 at time of admission to the hospital. Patients were excluded if theywere not able to complete the study questionnaires, e.g. due to insufficient knowledge of the Dutch language or in the case of severe, acute psychiatric co morbidity that required immediate medical attention, interfering with study participation (e.g. Delirium, mania, psychosis or suicidal tendencies). Participants for BZD treatment were those admitted at the psychiatric ward of the Sint-Erasmus Hospital (part of Ziekenhuis Netwerk Antwerpen (ZNA) in Belgium (n=42) between October 2015 and May 2018, where BZD tapering is treatment-as-usual. Participants for pharmaceutical GHB tapering were selected from a historical sample (n=229) previously recruited, between March 2011 and December 2012, from six addiction treatment centres in The Netherlands (IrisZorg, Novad- ic-Kentron, Tactus, Victas, Mondriaan GGZ and Verslavingszorg Noord Nederland) (Dijkstra et al., 2017). Based on this sample a matched group (n=42) was selected. For matching a 3-step approach was used. First, based on the Belgium sample the range for age, months of daily GHB use and the daily dose of GHB before admission was determined. Second, all patients within the historical comparison group of pharmaceutical GHB tapering who scored outside these ranges on one or more variables were excluded. Next, we drew a random sample of 42 patients from this comparison sample. Written informed consent was obtained from all patients prior to data collection in both samples Measurements Socio demographics and substance use Demographics and other clinical data were obtained from chart reviews (admission data, discharge data and the discharge summary). Substance use and classification of substance dependence was assessed using the Measurement of Addicts for Triage and Evaluation (MATE) section one (Schippers et al., 2010). The MATE section one defines participants’ current substance use (last thirty days) and lifetime substance use. For GHB use, the GHB questionnaire was used (Dijkstra et al., 2017). This GHB questionnaire assesses the pattern of GHB use, including the total years of use, daily dose in ml, ml per dose and time interval between doses. Withdrawal symptoms Withdrawal severity was assessed using the Subjective and Objective Withdrawal Scale (SWS/OWS) (Handelsman et al., 1987). The SWS, a 5-point Likert scale (0-4) with a maximum score of 132, is filled out by patients and consists of 33 items related to withdrawal. It includes both mental and physical withdrawal items like “I feel anxious,” “I see things that aren’t there,” “I’m trembling” and “I’m tired”. The OWS is filled out by the nursing staff and is based on clinical observations. The scale consists of 33 items scored dichotomously (Yes or No).