Concomitant consumption of benzodiazepines (BZDs) and opioids is a major problem in patients with opioid dependence. It may have substantial impact on morbidity, mortality and clinical course. The current retrospective study aims to determine whether there are differences in the additional use of BZDs among addicts regularly taking methadone or codeine medications in treatment and untreated addicts injecting heroin. The records of 1,685 patients admitted for detoxification were analyzed using bivariate analysis and multiple logistic regression analysis. Demographic and drug related variables were considered, both as possible confounders and predictors of concomitant BZD use. Daily intake of BZDs was reported in 44.4% of the patients. Patients treated with methadone or codeine medications report daily intake of BZDs significantly more often than the heroin-dependent patients (p < 0.01). Using multiple regression analyses, the results were confirmed as independent from the assessed possible confounders. Further we found that daily use of alcohol or barbiturates, early onset of opioid use (p < 0.01), unemployment, having a substance dependent family member with, and a history of imprisonment (for all p < 0.05) were associated with concomitant daily consumption of BZDs in opioid dependent subjects. These finding underline the need to further explore the causes, interactions and consequences of concomitant BZD and opiate use.

Background/Aim: Injection drug users (IDUs) have a high risk of acquiring an infection with the human immunodeficiency virus (HIV). To improve counseling and prevention, a better understanding of risk factors and predictors for an infection must be gained. This retrospective study has the aim to determine the risk factors for acquisition of HIV infection other than sharing of needles/syringes. Methods: The study population consisted of all patients admitted to the detoxification unit between 1991 and 1996 who met ICD-10 criteria for opioid dependency, who reported to share needles, and who agreed to have an antibody test. Possible risk factors were assessed by interview. Cross tables based on bivariate logistic regression were constructed to estimate the relative odds. Multiple logistic regression modeling procedures were used to adjust possible confounding factors. Results: A total of 1,049 out of 1,656 patients admitted were included into the study. 4.8% of the patients were HIV-1 seropositive. The prevalence was higher among older patients and among patients living with a significant other substance drug user with substance dependency, after a longer duration of drug use, and after coinfection with hepatitis B virus and/or hepatitis C virus (HCV). Using multiple logistic regression analyses and including all individually significant risk factors, we found only coinfection with HCV to remain significant. 92% of the HIV-infected patients were also HCV infected. In the group younger than 23 years of age, a total of 53.5% of the IDUs were still seronegative for HIV, hepatitis A and B virus, and HCV. Conclusions: Despite the high rate of HCV coinfection (92%) in HIV-infected patients, we found more than 50% of IDUs younger than 23 years to be neither infected with HCV nor with HIV. Early prevention strategies against infectious diseases should especially focus on young IDUs.