Dieter Ladewig

Double-blind randomized trial of buprenorphine and methadone in opiate dependence

This study compared the safety and efficacy of sublingual buprenorphine tablets with oral methadone in a population of opioid-dependent individuals in a double-blind, randomized, 6-week trial using a flexible dosing procedure. Fifty-eight patients seeking treatment for opioid dependence were recruited in three outpatient facilities and randomly assigned to substitution with buprenorphine or methadone. The retention rate was significantly better in the methadone maintained group (90 vs. 56%; P<0.001). Subjects completing the study in both the treatment groups had similar proportions of opioid positive urine samples (buprenorphine 62%; methadone 59%) and positive urine specimens, as well as mean heroin craving scores decreased significantly over time (P=0.035 and P<0.001). The proportion of cocaine-positive toxicology results did not differ between groups. At week six mean stabilization doses were 10.5 mg per day for the sublingual buprenorphine tablet, and 69.8 mg per day for methadone, respectively. Patient performance during maintenance was similar in both the groups. The high attrition rate in the buprenorphine group during the induction phase might reflect inadequate induction doses. Thus, buprenorphine is a viable alternative for methadone in short-term maintenance treatment for heroin dependence if treatment induction is done with adequate dosages.

Benzodiazepine prescribing to the Swiss adult population: results from a national survey of community pharmacies.

The purpose of the study was to assess prevalence of benzodiazepine use in the Swiss adult population and to assess on benzodiazepine prescription patterns of physicians in domiciliary practice. Study designA retrospective, population-based cross-sectional study with 520 000 patients covering a 6-month period. MethodsWe estimated the prevalence, amount and duration of benzodiazepine use using a pharmacy dispensing database. ResultsOf all patients, 9.1% (n=45 309) received at least one benzodiazepine prescription in the 6-month period. Most persons receiving benzodiazepine prescriptions were women (67%), and half of all patients were aged 65 or older. Of 45 309 patients with benzodiazepine prescriptions, 44% (n=19 954) had one single prescription, mostly for a short period (<90 days) and in lower than the recommended dose range. Fifty-six percent (n=25 354) had repeated benzodiazepine prescriptions, mostly for a long time period (>90 days), and in lower than the recommended or within the recommended dose range. In patients with long-term use (n=25 354), however, 1.6% had benzodiazepine prescriptions in extremely high doses. The sample of patients with repeated prescriptions allowed an estimation of a benzodiazepine use of 43.3 daily defined doses per 1000 inhabitants in Switzerland. ConclusionsBenzodiazepine prescriptions were appropriate for most patients and thus were prescribed in therapeutic doses, as indicated in the treatment guidelines. On the other hand, our survey showed that 1.6% of the patients had prescriptions for long time periods at very high doses, indicating an abuse or dependence on benzodiazepines in this subgroup.

High prevalence and coinfection rate of hepatitis G and C infections in intravenous drug addicts

BACKGROUND/AIMS The hepatitis G virus is a newly discovered RNA virus which is possibly transmitted parenterally. Hepatitis G virus is associated with acute or chronic hepatitis and may lead to cirrhosis and liver cancer, characteristics shared by the hepatitis C virus. Hepatitis C virus is prevalent in drug users, but the frequency and role of hepatitis G virus is not yet well established. METHODS One hundred and seventeen heavy i.v. drug users were enrolled in a prospective, controlled, randomized study for i.v. administration of heroin and/or methadone. Hepatitis G virus was detected using a hot start polymerase chain reaction followed by an ELISA polymerase chain reaction assay. Hepatitis C virus genotyping was done using the Inno-Lipa strip assay. RESULTS Hepatitis G virus infection was detected in 35% (41/117) of the study population and hepatitis C virus infection in 95.7% (112/117). Ninety-seven percent of hepatitis G virus positive patients were coinfected with hepatitis C virus, of whom 75% were infected with hepatitis C virus genotype 3a. This genotype was prevalent in 48.3% of patients infected with hepatitis C virus alone. The presence or absence of hepatitis G virus infection had no influence on chronic hepatitis. Twenty-two percent of patients who started injecting heroin before 1980 and 40% of those who started after 1980 were hepatitis G virus positive. Overall, 16 patients were infected with human immunodeficiency virus, six were coinfected with hepatitis G virus and hepatitis C virus, and 10 only with hepatitis C virus. CONCLUSIONS Hepatitis G virus infection is highly prevalent in i.v. drug users, but less frequent than hepatitis C virus infection. The fact that all but two patients were coinfected with hepatitis C virus, 75% with one genotype, supports a common route of transmission for both viruses. The course of hepatitis C virus infection is not altered by hepatitis G virus infection.

Ethyl glucuronide: on the time course of excretion in urine during detoxification.

Ethyl glucuronide (EtG) is a promising new biological state marker of recent alcohol consumption that detects alcohol use reliably over a definite time period. Other currently available markers lack acceptable sensitivity and specificity. Our aim is to elucidate under naturalistic conditions the time course of EtG excretion in urine following alcohol consumption and to show how this can be utilized for monitoring and prognosis in patients. There are no other existing data on this issue to date. One hundred and thirty‐eight urine samples from 28 male alcohol withdrawal patients were drawn every 3‐24 hours for up to 94 hours after hospitalization. Breath ethanol concentration (mean) at hospitalization was 900 mg/L. Patient age in years was 40.3 (mean). Determination of urine EtG was performed by gas chromatography/mass spectrometry (GC/MS) with deuterium‐labelled EtG as an internal standard. The strongest correlations (p<0.01) were found between EtG determinations in the different patient when breath ethanol concentrations (BEC) were 0 and 48 hours after BEC=0 (r=0.747), EtG 24 and 48 hours after BEC=0 (r=0.872), and in the time frame of detection (hours) of EtG and EtG 48 hours after BEC=0 (r=0.762). No significant correlation was found (Mann‐Whitney test) between EtG concentrations in urine at different time points between the groups of patients with (a) 1 or less‐2, (b) 3‐4 or more previous hospitalizations, (c) a history of seizures (yes/no) or (d) an age above or below the median (40.5). EtG excretion in urine is not random, but seems rather to follow a kinetic profile. Furthermore our preliminary data indicate, that there is no significant difference for EtG concentration in urine when correlated to group variables such as age, seizures and hospitalizations.

Comparison of Buprenorphine and Methadone in the Treatment of Opioid Dependence

A three-centre, randomised, double-blind study was designed to compare the efficacy and safety of buprenorphine and methadone. This was the first European study to compare these agents and was based on a previous trial performed in the US. Opioid-dependent subjects were randomised to receive either sublingual buprenorphine or oral methadone daily. Both objective and subjective measures of efficacy were monitored weekly, and safety parameters were regularly monitored over the entire six-week study. Urinalysis showed that the two treatments were similar with a slight increase in opioid-negative urines noted in both groups. The retention rate in the buprenorphine group was lower than in the methadone group, although it has been suggested that the buprenorphine dose may have been too low for some patients. None of the side effects noted were considered serious and all were attributable to chronic opioid dependence. Experience of two years substitution treatment in Fribourg suggests that initial induction onto buprenorphine allows for patients to be subgrouped before being given the most appropriate maintenance agent. Further investigation is required into the different dose-related effects of buprenorphine seen in particular subsets of addicts.

Rapid cortical hemoglobin deoxygenation after heroin and methadone injection in humans: a preliminary report.

The short-term effects of intravenous opioids (heroin 20-300 mg, methadone 30-180 mg) on cortical hemoglobin oxygenation were examined by near infrared spectroscopy in ten opioid-dependent subjects and were compared with the effects of saline in ten age-matched normal controls. Heroin and methadone produced a rapid and dramatic decrease in cortical hemoglobin oxygenation. Saline had no effects. Opioid-induced acute deoxygenation of cortical hemoglobin is most likely associated with respiratory depression. Thorough medical monitoring is strongly recommended in intravenous opioid maintenance treatments.

Safety of injectable opioid maintenance treatment for heroin dependence

BACKGROUND There is a growing debate about injectable opioid treatment programs in many Western countries. This is the first placebo-controlled study of the safety of injectable opioids in a controlled treatment setting. METHODS Twenty-five opioid-dependent patients on intravenous (IV) heroin or IV methadone maintenance treatment were randomly assigned to either their individual prescribed IV maintenance dose or placebo. Acute drug effects were recorded, focusing on electrocardiography, respiratory movements, arterial blood oxygen saturation, and electroencephalography (EEG). RESULTS After heroin injection, marked respiratory depression progressing to a Cheyne-Stokes pattern occurred. Peripheral arterial blood oxygenation decreased to 78.9 +/- 8.7% (mean +/- SD) ranging from 52%-90%. During hypoxia, 7 of the 16 subjects experienced intermittent and somewhat severe bradycardia. Five subjects exhibited paroxysmal EEG patterns. After methadone injection, respiratory depression was less pronounced than after heroin injection. No relevant bradycardia was noted. CONCLUSIONS Opioid doses commonly prescribed in IV opioid treatment induce marked respiratory and circulatory depression, as well as occasionally irregular paroxysmal EEG activity. Further studies are needed to optimize the clinical practice of IV opioid treatment to prevent serious complications. Moreover, the extent of the observed effects raises questions about the appropriateness of IV opioid treatment in the present form.

Onset and pattern of substance use in intravenous drug users of an opiate maintenance program.

OBJECTIVES To assess the initiation of substance use of participants in an opiate maintenance program by a cross-sectional survey. METHOD Participants (n=184) filled out a questionnaire assessing age at initial substance use and age at onset of regular drug use. RESULTS Of 15 substances investigated, alcohol, nicotine, analgesics and marijuana were initiated and consumed regularly before the age of 18 years. Barbiturates, benzodiazepines, cocaine, and opiates were begun later. The time gap between initial and regular use varied depending on the substance. Regular use exceeded 50% for alcohol, benzodiazepines, cocaine, heroin, marijuana and nicotine. CONCLUSIONS Specific knowledge about the age of onset and sequence of substances used by drug addicts may help to prevent substance use more age specifically.

The role of beta-carbolines (harman/norharman) in heroin addicts.

Endogenous substances resulting from interactions between alcohol and possibly opioid metabolites and neurotransmitters (dopamine, indolamines) could be mediators of the pathochemical process towards dependence. Beta-carbolines (harman/norharman) are increased in alcoholics and - according to the presented results - in heroin addicts. Psychopathological disorders such as anxiety or depression do not seem to influence the level of beta-carbolines.

Changes in EEG, blood levels, mood scales and performance scores during long term treatment with diazepam, phenobarbital or placebo in patients

1. The patient population consisting of fifteen patients was divided into three groups, namely: diazepam group, phenobarbital group and placebo group. After three weeks the medicated groups were switched to placebo for a week and the placebo group was given phenobarbital. 2. The parameters to be assessed once a week comprised frequency-analyzed EEG recordings, performance in two attention tests and subjectively estimated mood modalities. 3. The EEG analysis suggested that EEG patterns: a) were drug-dependent, with a differential distribution for each drug of the four frequency bands analyzed; b) showed no change during the three-week treatment period; c) changed on cessation of medication or on switch from placebo to active medication; d) were task-dependent and changed in a systematic way with the level of activation (stress, vigilance or relaxation). 4. The results would allow a better understanding of the clinical course, the choice of therapeutic measures and of the underlying mechanisms of action.