Prevalence of high-risk drug use and coverage of opioid substitution treatment and needle and syringe programs in Lithuania in 2015-2016: A multi-method estimation study.

BACKGROUND AND OBJECTIVES: In Lithuania, injecting heroin and other illicit opioids has dominated high-risk drug use since about 2000. More recently, patients have reported a high-risk use of amphetamines. Newly diagnosed HIV cases among people who inject drugs peaked in 2002 and 2009 and drug-related deaths have been on the increase. Yet research has reported a limited number of available harm-reduction programs. This study aimed to estimate the size of high-risk drug using populations in Lithuania and to apply these estimates in assessing the coverage of opioid substitution treatment (OST) and needle and syringe programs (NSP). METHODS: We used indirect prevalence estimation methods (HIV and Mortality Multiplier, Capture-Recapture, Truncated Poisson and the Multivariate Indicator Method) to obtain annual prevalence estimates of the population of high-risk opioid users (HROU) and of people who inject drugs (PWID) in Lithuania in 2015/2016. We computed the coverage of OST (the annual percentage of HROU in these programs) and NSP (the number of provided syringes per PWID per year), using the prevalence estimates and the data from drug services. RESULTS: There were between 4854 and 12,444 HROU and between 8371 and 10,474 PWID in Lithuania in 2015/2016. In addition, we obtained a preliminary estimate of 4742-7000 high-risk amphetamine users. This constitutes around 2.5-6.5 HROU and 4.4-5.3 PWID per 1000 inhabitants aged 15-64. On average, 9.9-25.5% of HROUs were in OST and an average PWID in Lithuania obtained 19-29 syringes via NSPs during the study period. CONCLUSIONS: While the current prevalence of high-risk drug use in Lithuania is comparable to other European countries and for PWID, it is above the average; and the coverage of OST and NSP services in this population is markedly lower than in most countries of the European Union and warrants further investment.

The choice of screening instrument matters: the case of problematic cannabis use screening in spanish population of adolescents.

The aim of this study was to examine the feasibility of problem cannabis use screening instruments administration within wide school surveys, their psychometric properties, overlaps, and relationships with other variables. Students from 7 Spanish regions, aged 14-18, who attended secondary schools were sampled by two-stage cluster sampling (net sample 14,589). Standardized, anonymous questionnaire including DSM-IV cannabis abuse criteria, Cannabis Abuse Screening Test (CAST), and Severity of Dependence Scale (SDS) was self-completed with paper and pencil in the selected classrooms. Data was analysed using classical psychometric theory, bivariate tests, and multinomial logistic regression analysis. Not responding to instruments' items (10.5-12.3%) was associated with reporting less frequent cannabis use. The instruments overlapped partially, with 16.1% of positives being positive on all three. SDS was more likely to identify younger users with lower frequency of use who thought habitual cannabis use posed a considerable problem. CAST positivity was associated with frequent cannabis use and related problems. It is feasible to use short psychometric scales in wide school surveys, but one must carefully choose the screening instrument, as different instruments identify different groups of users. These may correspond to different types of problematic cannabis use; however, measurement bias seems to play a role too.