Harmen Beurmanjer

151 Supplements Population description and results Demographics: 67.7% male; over 30 years (40.0%); Median annual household income (x10.000 dollars): 5.2; Median home value (x100.000 dollars): 3.4; mainly urban participants. GHB use: Reported GHB dependence in 18% of cases. Likelihood of major GHB adverse health outcomes increased 40% for every 100,000 dollar increase in median home values. There was a similar association regarding household income and related to 3 out of 4 high-risk behaviours (GHB dependence, GHB congener use, and co-use of other substances). Other substance use: Co-use with other substances (16%) and alcohol alone (20%) at any time. Reported polydrug-use in past in 33.3%: alcohol (20.5%), amphetamine (6.7%), benzodiazepine (4.3%), cocaine (2.9%), cannabis (1.9%), MDMA (1.4%), opiates (1.0%), ketamine (0.5%), thyroid (0.5%), and SSRI’s (0.5%). Demographics: 55 % male (percentage of women increased from 38% to 60% between 1999 and 2003); M=27, SD=9 years; No/moderate income (26%), moderate (59%). GHB use: 76% decrease of reported GHB cases from 1999 (n=426) to 2003 (n=101). Moderate severity in 59% of the cases. Other substance use: Polydrug use was common. Alcohol use (self-reported) in 59% and 21% by laboratory testing. Laboratory results (n=152): ecstasy (29%), amphetamines (24%), cocaine (12.5%), cannabis (12%), benzodiazepines (10%). Demographics: 57% male (n=4), M=21.9 years. GHB use: Only substance GHB in 1 case. Other substance use: 6 cases with co-ingestion of other substances; most mentioned were alcohol (n=3) and heroin (n=3). Demographics: 49% male (group A) and 57% (group B); Median 24 (range 22-27) years (group A) and median 25 (range 23-29) years (group B). Other: Location: group A: private (10%), public indoors (41%), and outdoors (41%); group B: private (25%), public indoors (18%), and outdoors (53%). Other substance use: history of injecting drug-use 33% (group A) and 59% (group B). Polydrug and alcohol use was 80% (group A) and 62% (group B).