Validations of khat use disorder using DSM-5 criteria and assessments of clinically meaningful withdrawal syndromes among frequent khat users

Khat (a natural stimulant plant) has become a public health concern due to adverse health risks and negative social functioning associated with frequent chewing. Increased frequency of khat use is associated with use disorder, dependence and increased physical and psychological health problems. Despite the prevalence of khat use and increasing consumption and use disorder in Ethiopia, there has been inadequate and insufficient research available to understand its potential psychological and health consequences. In the Ethiopian context, very little is known about the nature of khat dependence, the outcome of khat cessation attempts and the characteristics of withdrawal symptoms and craving during khat abstinence. Hence, the main aims of the studies in this thesis is to validate the existence of a khat use disorder syndrome using DSM-5 criteria and to explore the nature and the time course of any withdrawal syndrome in relation to the cessation of khat use among frequent khat users. In Study 1 of this thesis, the presence of khat use disorder syndrome was validated using DSM-5 criteria and its relationship with increased experience of harms was examined on a sample of 400 current khat-chewers (aged 16 and above recruited from khat markets and cafes from university and general community in Adama, Ethiopia) between September 2014 and January 2015. Accordingly, 10.5% (95% CI=7.9– 13.9) were categorized as experiencing mild, 8.8% (95% CI=6.4–12.0) moderate and 54.5% (95% CI=49.6–59.3) severe khat use disorder. Participants demonstrated increased financial, academic and self-reported mental health problems associated with use. Participants with khat use disorder also had higher psychological distress and poorer quality of life. Despite this, there are low levels of help-seeking for these problems. Only one-third (32.9%) of individuals with khat use disorder reported life-time access to help-seeking largely from friends and relatives. Hence, the construct of a substance use disorder syndrome for khat using DSM-5 criteria appears valid and performs in a manner consistent with other substances of dependence In Study 2, a Cross-sectional data from a sample of 388 past year khat consumers (same participants used in study 1) were collected to determine the efficacy of the Severity of Dependence Scale (SDS) as a screening tool for DSM-5 defined Khat Use Disorder. Participants self-completed survey comprising an SDS scale, current substance use disorder symptoms (modified Alcohol Use Disorder and Associated Disabilities Interview Schedule-IV), and validated measures of health, psychological distress, quality of life and academic functioning. Nearly three-quarters (73%) of the sample experienced DSM-5 Khat Use Disorder. The SDS demonstrated excellent discrimination (AUC=0.92), with an optimal cut-off score of 3 or above. Those screened positive had more frequent and higher dose of khat use; greater financial problems in relation to khat use; more problems related to academic functioning in daily life; greater psychological distress and poorer quality of life than their counter partners. The SDS, as a brief and simple screening tool, appears to validly identify individuals with khat use disorder syndrome and higher rates of adverse consequences. Hence, there is clear evidence that some consumers are both concerned with their use and experience problems in relation to khat use. In Study 3, a naturalistic data collected from 59 daily and near daily khat consumers (from Adama University in Ethiopia) using electronic diary, were used to monitor the outcomes of an unassisted quit attempt and to examine predictors of success of khat abstinence. While 80%, reached at least 7 continuous days of abstinence, 93% lapsed, on the average, after 11 days post-quit (SD=7) and only 7% maintained continuous abstinence for 28 days post-quit. Although regular khat chewers have motivation and desire to quit, they seem to have difficulties maintaining abstinence with unassisted quit attempts. Treatment aids are very likely to assist chewers in their quit attempts. None of the demographic factors were predictive of successful abstinence. In Study 4, the elevation and shape of the growth curves of the major withdrawal symptoms and craving of frequent khat chewers (participants used in study 3) were examined for 3 pre-quit and 14post-quit days. Electronic Diary (ED) was used to collect real time data of khat withdrawal symptoms and cravings. The development of withdrawal symptoms was evident, and all withdrawal symptoms followed similar overall patterns with salient elevations after the quit day and curvatures around the first week of post quit period, indicating the persistence and severity of these symptoms over time. In addition, craving, irritability and restlessness had significantly reverted to their baseline level during the 2nd week of the post quit period. The need for interventions is necessary to support individuals during the period of increased symptoms of dysphoria and to reduce the risk of relapse. Participants’ anticipation to quit and the initial quitting experience were likely to intensify withdrawal symptoms and provoke lapse in the long run. In conclusion, khat chewing has multiple effects on frequent and chronic consumers. While khat is a mild stimulant, there is clear evidence of khat use disorder and that some khat users are both concerned with their use and experience substantial and clinically significant problems associated with their use. The SDS, being a brief screening tool, appears to validly identify individuals with khat use disorder syndrome and with high rates of adverse consequences. In addition, self-motivated individuals for unassisted quit attempts seem to experience difficulties in maintaining abstinence since expectation of the quit experience by itself is likely to intensify withdrawal symptoms and craving among the chewers and facilitate eventual lapse. Hence, there is considerable scope to intervene at an organizational level to curb and minimize problems in relation to khat