To determine the seroprevalence of hepatitis B (HBV), hepatitis C (HCV) and HIV infections in problem drug users (PDU) in Luxembourg. To measure the validity of self-reported test results provided by study participants as well as obtained through the national drug-monitoring system (RELIS).
In a cross-sectional multisite study, data were collected by voluntary, anonymous and assisted questionnaires and serological detection of antibodies and antigens. Out of 1169 contacts, 397 participants were recruited within in and out-of-treatment settings (84.2% injecting drug users; IDU).
The prevalence of antibodies to HIV was 8/272 (2.9%; 95% CI 0.9% to 4.9%), to HCV 245/343 (71.4%; 66.6% to 76.2%), and 67/310 (21.6%; 17.1% to 26.2%) to total HBV antibodies and surface antigen (for IDU 5/202, 218/268 and 59/239, respectively). Specificity of study self-reports was very high for HBV and perfect for HCV and HIV. Sensitivity was 0.224, 0.798 and 0.800, respectively. Kappa scores provided degrees of agreement between serological tests and study self-reports of 0.89 for HIV, 0.65 for HCV and 0.25 for HBV. In contrast to simultaneous cross-sectional self-reports, secondary self-reported data (RELIS) showed high agreement for HIV and HBV infections and provided a good proxy for estimation of HCV seroprevalence.
HIV testing routines in PDU should be completed at least by HBV and HCV detection given the poor validity of cross-sectional self-reports on hepatitis infections. HIV and hepatitis prevalence estimations in PDU gain by relying on multisite/setting data collection. Research should further investigate the validity of HIV and hepatitis self-reports from routine drug-monitoring systems versus cross-sectional surveys.
- Date de parution: janvier 2012
- Alain ORIGER, Jean-Claude SCHMIT
- Editeur: BMJ
To estimate the prevalence of problem drug use (PDU) and injecting drug use (IDU) in Luxembourg and analyze trends between 1997 and 2009. To assess the feasibility of prevalence estimations based on drug use surveillance systems.
Serial multi-method PDU/IDU prevalence estimations based upon capture-recapture, Poisson regression, multiplier and back-calculation methods. Comparative analysis of methods and assessment of their robustness to variations of external factors.
National PDU and IDU prevalence rates were estimated at 6.16/1,000 (95% CI 4.62/1,000 to 7.81/1,000) and 5.68/1,000 (95% CI 4.53/1,000 to 6.85/1,000) inhabitants aged 15-64 years, respectively. Absolute prevalence and prevalence rates of PDU increased between 1997 and 2000 and declined from 2003 onwards, whereas IDU absolute prevalence and prevalence rates witnessed an increasing trend between 1997 and 2007.
Drug use surveillance systems can be valuable instruments for the estimation and trend analysis of drug misuse prevalence given multiple methods are applied that rely on serial and representative data from different sources and different settings, control multiple counts and build upon standardized and sustained data collection routines. The described institutional contact indicator revealed to be a useful tool in the context of PDU/IDU prevalence estimations and thus contributes to enhancing evidence-based drug policy planning.
- Date de parution: octobre 2012
- Alain ORIGER
- Editeur: Karger