Cardiac autonomic modulation during methadone therapy among heroin users: A pilot study

Background

Methadone therapy benefits heroin users in both the medical and psychosocial dimensions. However, both heroin and methadone have cardiac toxicity. Only limited information is available describing the changes in cardiac autonomic function of heroin users and effects of methadone therapy. We conduct the current study to explore the cardiac vagal function in heroin users as well as the impact of lapse and methadone therapy.

Methods

80 heroin users from a methadone therapy clinic were distributed into 31 compliant and 49 incompliant patients according to whether they lapsed into heroin use within 10 days. 40 healthy control subjects were recruited from the community. Participants underwent electrocardiographic recordings and the heroin users were further investigated before and after methadone therapy. Spectral analysis of heart rate variability (HRV) was computed for cardiac parasympathetic modulation (high-frequency power, HF) and cardiac sympathetic modulation (normalized low-frequency power, LF%).

Results

The baseline HRV parameters found lower HF values for heroin users and lower RR interval values for patients with a recent lapse compared with the healthy control subjects. After 1 h of methadone administration, heroin users who had lapsed showed a significant increase in HF but the heroin users who had not lapsed did not.

Conclusion

Our findings suggest that heroin users show decreased cardiac vagal activity and that methadone therapy immediately facilitates vagal regulation in patients with a recent lapse. The differential patterns of autonomic alteration under methadone between those with and without lapse might offer an objective measure of lapse.     

Australian Trends in Drug User and Drug Dealer Arrest Rates: 1993 to 2006–07

There is a paucity of data available in a concise, accessible form that maps trends in illicit drug crime offences for different types of drugs. The aim of the current article was to collate data on arrests for illicit drugs, examine trends for the main illicit drug types, and explore some potential explanations for emergent trends. Trends for provider-type and consumer-type offences are reviewed in terms of the number of offences per year, and the proportion of total illicit drug offences for each year for each type of drug across the period 1993 to 2006–07. The main findings are: (a) substantially more users than dealers are arrested, (b) the stability of the ratio between consumer-type and provider-type arrests suggests a longstanding law enforcement focus on targeting drug users relative to drug dealers, (c) cannabis arrests consistently account for the greatest proportion of arrests, (d) the proportion of total provider-type arrests for cannabis decreased by 30% between 1993 and 2006–07, (e) heroin arrests peaked in 1998–1999, then declined rapidly around the time of the Australian heroin shortage, and have showed a decline since that time, and (f) arrests for amphetamine-type stimulants and phenethylamines have steadily increased between the early 1990s through to 2006–07. Potential explanations for trends in drug arrests are posited, such as changes in the prevalence of use and shifts in law enforcement focus. The methodological weaknesses of the data are summarized and areas for future research are suggested.     

The effects of alcohol and illicit drugs on the human embryo and fetus

Women at childbearing age often use alcohol and various illicit drugs such as cocaine and heroin. These agents pass through the human placenta and may affect the developing embryo and fetus. Indeed, large amounts of alcohol ingested by the pregnant woman may produce a specific syndrome manifested by prenatal and postnatal growth retardation, a variety of facial dysmorphic features and mental retardation. Ingestion of smaller amounts of alcohol will produce the fetal alcohol effects with only few and minor dysmorphic features but with developmental delay and some degree of intellectual impairment. Cocaine use during pregnancy may apparently result in an increase in the rate of congenital anomalies, of stillbirth and of intrauterine growth retardation. The use of heroin and opiates does not seem to increase the rate of major congenital anomalies, but it reduces fetal growth and increases the rate of intrauterine fetal death. Studies on the developmental outcome of children born to cocaine or heroin dependent mothers seem all to show psychomotor developmental delay at a young age. At school age these children have intellectual impairment and a very high rate of inattention and/or hyperactivity. We should therefore address our efforts in improving the environment of these children and in treating the early symptoms of inattention and hyperactivity, even before the child reaches school.     

Neuropathology of substance use disorders

Addictions to licit and illicit drugs are chronic relapsing brain disorders that affect circuits that regulate reward, motivation, memory, and decision-making. Drug-induced pathological changes in these brain regions are associated with characteristic enduring behaviors that continue despite adverse biopsychosocial consequences. Repeated exposure to these substances leads to egocentric behaviors that focus on obtaining the drug by any means and on taking the drug under adverse psychosocial and medical conditions. Addiction also includes craving for the substances and, in some cases, involvement in risky behaviors that can cause death. These patterns of behaviors are associated with specific cognitive disturbances and neuroimaging evidence for brain dysfunctions in a diverse population of drug addicts. Postmortem studies have also revealed significant biochemical and/or structural abnormalities in some addicted individuals. The present review provides a summary of the evidence that has accumulated over the past few years to implicate brain dysfunctions in the varied manifestations of drug addiction. We thus review data on cerebrovascular alterations, brain structural abnormalities, and postmortem studies of patients who abuse cannabis, cocaine, amphetamines, heroin, and “bath salts”. We also discuss potential molecular, biochemical, and cellular bases for the varied clinical presentations of these patients. Elucidation of the biological bases of addiction will help to develop better therapeutic approaches to these patient populations.     

Visual-spatial attention in alcoholics and illicit stimulant abusers: effects of nicotine replacement

Reports of alcohol or illicit drug-related cognitive impairments have frequently disregarded the potentially confounding effects of smoking status and nicotine withdrawal on these measures. This study addressed this issue by measuring visual-spatial attention via an adaptation of the Posner paradigm in three groups of tobacco smokers: controls without a history of alcoholism or illicit drug use (n=27; 20 male), chronic alcoholics (n=22; 18 male), and illicit stimulant abusers (n=36; 21 male). Throughout testing, nicotine levels were stabilized by the double-blind administration of a high (14 or 21 mg) or low (7 mg) dose transdermal nicotine patch. A significant effect of group was observed for number of correct responses to restriction trials (F=5.48, 2/79 df; p=.006). Performance was normalized in the illicit stimulant group, and alcoholic participants exhibited superior performance relative to both illicit stimulant abusers (p=.002) and controls (p=.01). These findings support the hypothesis that nicotine may have a compensatory or normalizing effect on attentional functions in substance abusers. Whether these results reflect the central nervous system-activating effects of nicotine or merely alleviation of nicotine withdrawal is a topic of ongoing research.     

Comorbidity: cannabis and complexity

Cannabis is one of the most commonly used illicit drugs, and its effects have traditionally been seen as less harmful than outcomes associated with the highly prevalent use of alcohol and other illicit substances (e.g., cocaine and amphetamines), and injecting drugs. Consequently, less attention has been focused on developing and evaluating interventions in this area. However, current research supports the idea that cannabis does pose a number of acute and chronic health risks to the individual and to society. The authors review findings concerning the physiological and neurological effects of cannabis, prevalence of use, and studies concerning its possible role as a "gateway" drug. Diagnostic criteria for cannabis dependence and abuse are discussed, with a focus on whether a cannabis withdrawal syndrome exists and if so how it can be diagnosed. There is strong support for a link between cannabis and the development and exacerbation of psychosis and other mental health conditions (e.g., anxiety, depression). Further research is needed to determine the underlying neurochemical processes and their possible contribution to etiology, as well as the social factors that contribute to the increasing use of cannabis by young people. In addition there is a need for systematic evaluation using randomized controlled trials to determine effective prevention and treatment strategies. A number of public health programs that address cannabis use are reviewed along with available evidence for their effectiveness.     

Innovations in agonist maintenance treatment of opioid-dependent patients

PURPOSE OF REVIEW: To provide an overview of published studies on agonist maintenance treatment options for opioid-dependent patients. RECENT FINDINGS: The recent publication of controlled trials confirms earlier clinical evidence of the efficacy of diamorphine (heroin) in the treatment of opioid dependence. Findings show not only efficacy with respect to improvement of health, reduction of illicit drug use, reduction of criminality and stabilization of social conditions, but also cost effectiveness in the treatment of chronic treatment-resistant heroin addicts. SUMMARY: Agonist maintenance treatment has become the first-line treatment for chronic opioid dependence. High-quality studies demonstrate the effectiveness of a growing number of different agonist maintenance treatments for opioid dependence such as methadone and buprenorphine. In addition, there is new evidence for the effectiveness of other agonists, mainly slow-release morphine, intravenous and inhalable diamorphine and possibly oral diamorphine. Maintenance treatment with intravenous or inhalable diamorphine should be implemented into the healthcare system to treat a group of severely dependent treatment-resistant patients. Furthermore, the opioid-dependent patients not under treatment need to be engaged in maintenance treatments through other harm reduction measures. Agonist maintenance treatment is very effective in stabilizing the health condition and social situation, while also reducing harm, thereby increasing life expectancy and quality of life.     

Recidivism among male subjects incarcerated for illicit drug use in Taiwan

Illicit drug users are generally considered both patients and criminals in Taiwan. This study presents drug use behaviors and criminal recidivism of male subjects incarcerated for illicit drug use in Taiwan after detoxification at a detention center. This study also examined the relationship between drug use behaviors and subsequent recidivism. Charts and crime records of 794 male patients from the acute detoxification unit in a detention center in northern Taiwan were reviewed. These subjects were incarcerated for methamphetamine or/and heroin use. The authors examined the relationship between the variables collected during detoxification and subsequent recidivism of illicit drug use in the following 5 years after detoxification. Of 794 subjects, 539 (67.9%) were repeat offenders during the following 5 years after detoxification. Their recidivism occurred primarily within the first 2 years after being released into the community. The recidivism rate for heroin users was significantly higher than that of methamphetamine users. Aged under 30 years, a previous criminal record, and a positive urine analyses test for illicit drugs upon entering the detoxification unit were significantly associated with recidivism. Recidivism rates of illicit drug users in Taiwan after detoxification in the detention center were substantially high. The efficacy of detoxification programs at detention centers in Taiwan needs to be re-evaluated.     

Old patients suffering from long-standing schizophrenia: clinical aspects

Although some patients suffering from schizophrenia experience an age-related amelioration, a great number of people who are entering old age suffer from long-standing schizophrenia. These patients show specific psychiatric and somatic problems that must be taken into account. Firstly, some display high levels of all schizophrenic symptoms, while others experience changes in the symptom profile with aging, i.e. a reduction in positive symptoms and an increase in negative ones. Secondly, the occurrence of significant depressive symptoms among elderly patients with schizophrenia is well recognized. Thirdly, in recent years, studies have begun to shed more light on the trajectories of cognitive impairment of these patients in old age. Lastly, aged persons with schizophrenia often have side effects due to long-term antipsychotic medications and medical co-morbidity, more untreated somatic disorders (diabetes, cardiovascular diseases) and higher mortality rates. These may be the result of both lifestyle factors and lack of adequate medical care. Levels of adaptive functioning and quality of life are closely associated with clinical and social factors. Thus, we must consider all these different aspects in order to effectively manage the therapeutic and service needs of these patients.     

Electroencephalographic power and coherence analyses suggest altered brain function in abstinent male heroin-dependent patients

Previous studies have shown that drug abuse is associated with altered brain function. However, studies of heroin abuse-related brain dysfunctions are scarce. Electroencephalographic (EEG) power and coherence analyses are two important tools for examining the effects of drugs on brain function. In the present study, we compared EEG power and coherence measures of 18 abstinent heroin-dependent subjects with those of 12 healthy control subjects. Furthermore, within the heroin group, associations between heroin use in the past, heroin craving and these EEG measures were studied. The results show that heroin-dependent subjects have increased relative beta-2 power and increased left intrahemispheric gamma coherence compared with control subjects. Furthermore, coherence measures showed correlations with clinical variables. These EEG abnormalities may reflect underlying changes in brain function due to long-term drug abuse and premorbid characteristics.