Cocaine treatment demands in 10 western European countries: observed trends between 2011 and 2018.

AIMS: To describe cocaine treatment demand in 10 western European countries and to examine the size, direction and temporality of recent trends in the proportion of cocaine users among all clients entering treatment. DESIGN: Aggregated data collected through the European Union standardized treatment demand monitoring system (TDI) between 2011 and 2018 were used. SETTING: Belgium, England, France, Germany, Ireland, Italy, Luxembourg, Spain, Switzerland and the Netherlands. PARTICIPANTS: In total, more than 700 000 cocaine treatment records were analysed. Clients in treatment for cocaine as primary drug were predominantly male (85%), with an average age of 35 years. MEASUREMENTS: Number of treatment episodes for substance use and for cocaine as primary or secondary drug were collected year- and country-wise. When available, powder cocaine and crack and patients with and without previous treatment were differentiated. FINDINGS: Among the participating countries the share of cocaine as primary drug in treatment demand ranged between 4.7% [95% confidence interval (CI) = 4.6-4.9%] in Germany and 43.1% in Spain (95% CI = 42.6-43.5%). The general trend analysis showed a decreasing proportion of cocaine-related treatment entrants between 2011 and 2014 among all subgroups followed by a strong increase in 2015. The increase appeared stronger than for powder cocaine. Seven of 10 countries observed a recent significant increase in the proportion of treatment entrants reporting cocaine as the primary substance: Belgium [annual percentage change (APC) = 9.6%, P < 0.01], England (APC = 14.9%, P < 0.05), France (APC = 21.8%, P < 0.01), Ireland (APC = 28.2%, P < 0.01), Italy (APC = 7.8%, P < 0.01), Spain (APC = 7.0%, P < 0.05) and Switzerland (APC = 12.0%, P < 0.05). Trends were similar when looking at cocaine reported as primary or adjunctive substance. CONCLUSIONS: Despite substantial country-specific variation regarding cocaine prevalence and treatment demand, there has been an overall significant increase since 2015 in the share of cocaine-related treatment demand in western Europe.

A comparison of trends in wastewater-based data and traditional epidemiological indicators of stimulant consumption in three locations.

AIMS: To compare long-term trends in wastewater data with other indicators of stimulant use in three locations and to test the reliability of estimates based on 1 week of sampling. DESIGN: Comparison of trends in quantities ('loads') of stimulants or their metabolites in wastewater with trends in other indicators of stimulant use (e.g. treatment, police, population survey data). SETTING AND PARTICIPANTS: Populations in Oslo (Norway), South-East Queensland (Australia) and Eindhoven (the Netherlands). MEASUREMENTS: Wastewater data were modelled for MDMA (3,4-methyl​enedioxy​methamphetamine), benzoylecgonine (a metabolite of cocaine), amphetamine and methamphetamine in Oslo; benzoylecgonine in Eindhoven; and methamphetamine in South-East Queensland. Choice of stimulants modelled in each region was primarily determined by availability of useable data. FINDINGS: In Oslo, wastewater data, driving under the influence of drugs statistics and seizure data all suggested increasing MDMA use between 2009 and 2017. In South-East Queensland, there was an estimated 31.1% [95% confidence interval (CI) = 29.4-32.9%] annual increase in daily loads of methamphetamine in wastewater between 2009 and 2016, compared with a 14.1% (95% CI = 10.9-17.3%) annual increase in seizures. Some of the increase in wastewater can be explained by increased purity. In Eindhoven, there was no evidence of a change in cocaine consumption from wastewater, but a reduction was observed in numbers in treatment for cocaine use from 2012 to 2017. In approximately half the cases examined in Oslo, credible intervals around estimates of annual average loads from a regression model versus estimates based on a single week of sampling did not overlap. CONCLUSIONS: Long-term trends in loads of stimulants in wastewater appear to be broadly consistent with trends in other indicators of stimulant use in three locations. Wastewater data should be interpreted alongside epidemiological indicators and purity data. One week of wastewater sampling may not be sufficient for valid inference about drug consumption.

Long-Term Opioid Agonist Treatment Participation after First Treatment Entry is Similar across 4 European Regions but Lower in Non-Nationals.

Heroin users in opioid agonist treatment (OAT) show markedly reduced heroin consumption, less crime and a lower mortality rate. However, the extent of long-term OAT participation over subsequent treatment episodes remains unclear. We analysed the annual proportion of patients in treatment (at least 1 day) since the start of first OAT in 4 European regions: Barcelona (BA) 1996-2012: 8,602 patients; Czech -Republic (CZ) 2000-2014: 4,377 patients; Netherlands (NL) 1994-2014: 33,235 patients, Zurich (ZU) 1992-2015: 11,795. We estimated the long-term decline of treatment need due to mortality or abstinence and also a "nuisance" short-term decline until the equilibrium level of cycling in and out of OAT is reached to obtain the adjusted treatment participation value. The adjusted treatment participation was around 50% (BA: 47.4-51.4%; CZ: 49.8-53.9%; NL: 52.3-54.0%; ZU: 46.4-49.3%), and the annual decline of treatment need was close to 4%. Non-nationals (NL patients with a migrant background) showed substantial lower adjusted treatment participation (rate ratio BA: 0.059-0.343; NL: 0.710-0.751; ZU: 0.681-0.797; CZ: n.a.). Our method may provide a policy-relevant indicator of long-term provision, quality and access to OAT following first treatment.

Changes in cannabis potency and first-time admissions to drug treatment: a 16-year study in the Netherlands.

BACKGROUND: The number of people entering specialist drug treatment for cannabis problems has increased considerably in recent years. The reasons for this are unclear, but rising cannabis potency could be a contributing factor. METHODS: Cannabis potency data were obtained from an ongoing monitoring programme in the Netherlands. We analysed concentrations of δ-9-tetrahydrocannabinol (THC) from the most popular variety of domestic herbal cannabis sold in each retail outlet (2000-2015). Mixed effects linear regression models examined time-dependent associations between THC and first-time cannabis admissions to specialist drug treatment. Candidate time lags were 0-10 years, based on normative European drug treatment data. RESULTS: THC increased from a mean (95% CI) of 8.62 (7.97-9.27) to 20.38 (19.09-21.67) from 2000 to 2004 and then decreased to 15.31 (14.24-16.38) in 2015. First-time cannabis admissions (per 100 000 inhabitants) rose from 7.08 to 26.36 from 2000 to 2010, and then decreased to 19.82 in 2015. THC was positively associated with treatment entry at lags of 0-9 years, with the strongest association at 5 years, b = 0.370 (0.317-0.424), p < 0.0001. After adjusting for age, sex and non-cannabis drug treatment admissions, these positive associations were attenuated but remained statistically significant at lags of 5-7 years and were again strongest at 5 years, b = 0.082 (0.052-0.111), p < 0.0001. CONCLUSIONS: In this 16-year observational study, we found positive time-dependent associations between changes in cannabis potency and first-time cannabis admissions to drug treatment. These associations are biologically plausible, but their strength after adjustment suggests that other factors are also important.

Treatment consumption and treatment re-enrollment in GHB-dependent patients in The Netherlands.

BACKGROUND: The objective of this study was to assess treatment consumption and re-enrollment in treatment in patients with gamma-hydroxybutyrate (GHB)-dependence in Dutch Addiction Treatment Centers (ATCs) in comparison with other addictions. METHODS: A cohort-study using nationwide administrative data from regular Dutch ATCs associated with the Dutch National Alcohol and Drugs Information System (LADIS), covering an estimated 95% of ATCs. We selected in- and out-patients with alcohol, drug and/or behavioral addictions with a first treatment episode in 2008-2011 and consecutive treatments until 2013 (n=71,679). Patients still in treatment at that date (n=3686; 5.1%), forensic patients (n=1949; 2.7%) and deceased patients (n=570; 0.8%) were excluded, leaving 65,474 patients (91.3%). Of those, 596 (0.9%) patients had GHB dependence. We analyzed number of treatment contacts, treatment duration, admissions and admission duration of the first treatment episode, and re-enrollment (defined as having started a second treatment episode in the study period). RESULTS: GHB-dependent patients showed the highest number of treatment contacts, duration of treatment and chance of being admitted. Re-enrollment rates were 2-5 times higher in GHB-dependent patients than other patients with adjusted HR of other addictions ranging from 0.18 (95% confidence interval [CI]: 0.15-0.21) to 0.53 (95% CI: 0.47-0.61). CONCLUSIONS: This study demonstrates high levels of treatment consumption and high rates of treatment re-enrollment in GHB-dependent patients. These findings highlight the urgency of developing effective relapse prevention interventions for GHB-dependent patients.