Opiate antagonists in children and adolescents

Prevalence of Polypharmacy and Inappropriate Medication in Adults With Intellectual Disabilities in a Hospital Setting in Switzerland

Background: Polypharmacy and inappropriate prescription are frequent in vulnerable and multi-morbid populations. Adults with intellectual disability (ID) are at risk of being polymedicated because they often present with multiple comorbidities and challenging behaviors. Aim: The objective of this study was thus to evaluate the prevalence of potentially inappropriate medications (PIM) and polypharmacy in a hospital unit dedicated to adults with ID. Methods: A 10-month prospective observational study took place at a hospital unit specializing in the care of adults with ID in Geneva, Switzerland. Once a week, health and prescription data were collected and screened for PIM according to preset definitions. Results: Fourteen patients consented to participate, leading to 20 hospitalization events assessed during the study. Hospitalizations lasted 12.8 weeks on average. ID severities ranged from mild to profound, all degrees of severity being equally represented. One hundred percent of the patients were polymedicated (defined as five drugs or more prescribed simultaneously). A mean number of 9.4 drugs were prescribed per week, including 5.3 psychotropic drugs. The number of prescribed drugs remained stable throughout the hospitalizations. Antipsychotics were the most prescribed drug class (19% of all prescribed drugs), followed by benzodiazepines (13%) and laxatives (12%). A total of 114 PIM were recorded with an average of 5.7 PIM per hospitalization. Conclusions: This study showed that polypharmacy and inappropriate prescription are very common in adults with ID, even though the literature and expert positions advocate for deprescription in these patients. Specific prescribing and deprescribing guidelines are needed for that specific population.

Anorexia nervosa: a unified neurological perspective

The roles of corticotrophin-releasing factor (CRF), opioid peptides, leptin and ghrelin in anorexia nervosa (AN) were discussed in this paper. CRF is the key mediator of the hypothalamo-pituitary-adrenal (HPA) axis and also acts at various other parts of the brain, such as the limbic system and the peripheral nervous system. CRF action is mediated through the CRF1 and CRF2 receptors, with both HPA axis-dependent and HPA axis-independent actions, where the latter shows nil involvement of the autonomic nervous system. CRF1 receptors mediate both the HPA axis-dependent and independent pathways through CRF, while the CRF2 receptors exclusively mediate the HPA axis-independent pathways through urocortin. Opioid peptides are involved in the adaptation and regulation of energy intake and utilization through reward-related behavior. Opioids play a role in the addictive component of AN, as described by the "auto-addiction opioids theory". Their interactions have demonstrated the psychological aspect of AN and have shown to prevent the functioning of the physiological homeostasis. Important opioids involved are β-lipotropin, β-endorphin and dynorphin, which interact with both µ and κ opioids receptors to regulate reward-mediated behavior and describe the higher incidence of AN seen in females. Moreover, ghrelin is known as the "hunger" hormone and helps stimulate growth hormone (GH) and hepatic insulin-like-growth-factor-1(IGF-1), maintaining anabolism and preserving a lean body mass. In AN, high levels of GH due to GH resistance along with low levels of IGF-1 are observed. Leptin plays a role in suppressing appetite through the inhibition of neuropeptide Y gene. Moreover, the CRF, opioid, leptin and ghrelin mechanisms operate collectively at the HPA axis and express the physiological and psychological components of AN. Fear conditioning is an intricate learning process occurring at the level of the hippocampus, amygdala, lateral septum and the dorsal raphe by involving three distinct pathways, the HPA axis-independent pathway, hypercortisolemia and ghrelin. Opioids mediate CRF through noradrenergic stimulation in association with the locus coeruleus. Furthermore, CRF's inhibitory effect on gonadotropin releasing hormone can be further explained by the direct relationship seen between CRF and opioids. Low levels of gonadotropin have been demonstrated in AN where only estrogen has shown to mediate energy intake. In addition, estrogen is involved in regulating µ receptor concentrations, but in turn both CRF and opioids regulate estrogen. Moreover, opioids and leptin are both an effect of AN, while many studies have demonstrated a causal relationship between CRF and anorexic behavior. Moreover, leptin, estrogen and ghrelin play a role as predictors of survival in starvation. Since both leptin and estrogen are associated with higher levels of bone marrow fat they represent a longer survival than those who favor the ghrelin pathway. Future studies should consider cohort studies involving prepubertal males and females with high CRF. This would help prevent the extrapolation of results from studies on mice and draw more meaningful conclusions in humans. Studies should also consider these mechanisms in post-AN patients, as well as look into what predisposes certain individuals to develop AN. Finally, due to its complex pathogenesis the treatment of AN should focus on both the pharmacological and behavioral perspectives.

Non-suicidal self-injurious behavior, endogenous opioids and monoamine neurotransmitters

BACKGROUND

Self-inflicted injury, including cutting or burning, is the most frequent reason for psychiatric visits to medical emergency departments. This behavior, particularly when there is no apparent suicidal intent, is poorly understood from both biological and clinical perspectives.

OBJECTIVE

To examine the role of endogenous opioids and monoamine neurotransmitters in non-suicidal self-injury (NSSI).

METHODS

We compared cerebrospinal fluid (CSF) levels of endogenous opioids, 5 hydroxyindolacetic acid (5-HIAA) and homovanillic acid (HVA) in individuals with a history of repetitive non-suicidal self-injury with a diagnostically-matched group of individuals who had never engaged in non-suicidal self-injury. History of suicidal behavior, demographic background and psychopathology was assessed. All patients were diagnosed with a Cluster B personality disorder (i.e. borderline, antisocial, narcissistic or histrionic) (N=29) and had a history of at least one suicide attempt. Fourteen participants had a history of repeated non-suicidal self-injurious behavior (NSSI) in adulthood and 15 did not (no NSSI).

RESULTS

The NSSI group had significantly lower levels of CSF beta-endorphin and met-enkephalin when compared with the non-NSSI group. CSF dynorphin, HVA and 5-HIAA levels did not differ. Severity of depression, hopelessness and overall psychopathology was greater in the NSSI group.

CONCLUSION

beta-endorphin and met-enkephalin, opioids acting upon receptors involved in mediating stress-induced and physical pain analgesia respectively, are implicated in NSSI. Serotonergic and dopaminergic dysfunctions do not appear to be related to NSSI. Based on our findings, we propose a model of non-suicidal self-injury. Our results suggest that drugs acting on the opioid system warrant exploration as pharmacological treatments for NSSI.

Elimination diets in autism spectrum disorders: any wheat amidst the chaff?

The use of complementary or alternative treatment approaches in children with autism spectrum disorders (ASDs) is increasing, and the most popular of such approaches are diets that eliminate either gluten or casein, or both. The popularity of these diets indicates a need for more rigorous research into their efficacy. Owing to significant methodological flaws, the currently available data are inadequate to guide treatment recommendations. The purpose of this review is to examine the available trials of gluten/casein diets in children with ASDs regarding the strength of their findings and also concerning points that may be useful in the design of future studies. Seven trials of these diets in ASD are critically reviewed; 6 of these were uncontrolled trials and 1 used a single-blind design. All reported efficacy in reducing some autism symptoms, and 2 groups of investigators also reported improvement in nonverbal cognition. Design flaws in all of the studies weaken the confidence that can be placed in their findings. Careful double-blind, placebo-controlled studies are needed to evaluate whether actual benefit undergirds the diets' popularity and to provide better guidance to clinicians and caregivers. The literature currently available suggests that diets eliminating both gluten and casein (rather than either alone) should be studied first and that outcome measures should include assessments of nonverbal cognition.

Perinatal ethanol exposure alters met-enkephalin levels of male and female rats

This study used a rat model of Fetal Alcohol Syndrome to investigate whether combined prenatal and postnatal ethanol exposure affects met-enkephalin levels in the brains of male and female Long-Evans adult rats. Intragastric ethanol was administered to a group of rats (ET) from gestational day (GD) 1 through 22 and from postnatal day (PD) 2 through 10. The control groups consisted of a nontreated control group (NTC) and an intubated control group (IC) that received the intragastric intubation procedure but no exposure to ethanol. We measured met-enkephalin levels in the prefrontal cortex, nucleus accumbens, hypothalamus, central and basolateral nucleus of amygdala and ventral tegmental area. Met-enkephalin levels in the hypothalamus of male and female ET animals were significantly higher than those in either the NTC or IC animals. Met-enkephalin levels in the central nucleus of the amygdala of male and female ET animals were significantly lower than the levels in the NTC animals. Met-enkephalin levels in the nucleus accumbens of ET females were significantly greater than those in the IC females. These results demonstrate that the combination of prenatal and postnatal ethanol exposure affects basal met-enkephalin levels in specific regions in a sex-specific manner. These changes in met-enkephalin levels may explain how early ethanol exposure affects opioid-regulated behaviors such as social play, sexual behavior, and other social behaviors.

Effects of naltrexone on the acquisition of alcohol intake in male and female periadolescent and adult alcohol-preferring (P) rats

The objective of this study was to compare the effects of naltrexone (NTX) on the acquisition of alcohol drinking, during periadolescence and adulthood in rats using a rodent model of alcoholism. Periadolescent and adult alcohol-preferring (P) rats of both sexes were given access to water and 15% (v/v) alcohol 24-hr/day for 45 days. Alcohol access started at 1200 hr on post-natal day (PND) 30 for the periadolescent rats and approximately PND 90 for the adult rats. Subcutaneous (SC) injections of NTX (0, 5, 10, 20, and 30 mg/kg) were administered daily between 1600-1700 hr to separate groups of animals during the first 10 days of alcohol access. During the treatment period, differential effects on alcohol intake were seen between periadolescent and adult animals: (a) lower doses of NTX were more effective in the periadolescent than the adult P rats, and (b) greater tolerance to repeated dosing was displayed by adult, compared with periadolescent, rats. By the 20h day of alcohol access there were no significant differences between the NTX dose groups. Additionally, there were no sex of animal differences at the ages tested. These findings indicate that the endogenous opioid system(s) mediating alcohol intake are developmentally present in periadolescent P rats, such that NTX not only interfered with the acquisition of alcohol intake by adolescent P rats but appeared to also have a greater effect than that observed in adult P rats. Therefore, NTX may serve as an effective treatment in reducing alcohol abuse and dependence in genetically, and perhaps environmentally, at-risk youth.

Disordered gambling in adolescents : epidemiology, diagnosis, and treatment

Rapid expansion of legalized gambling has been associated with increased rates of gambling disorders among adults and adolescents worldwide. Epidemiologic studies suggest that, in North America, up to 6% of adults and 20% of adolescents have a gambling problem. Despite increasing prevalence rates of gambling disorders, little research is available on how to treat such disorders in adolescents. Much of what is known about how to treat adolescent problem and pathological gambling comes from research on psychosocial and psychopharmacologic treatments for adult pathological gambling. Risk factors for adolescent gambling disorders include male gender, alcohol and drug use, deviant peers, family history of gambling, and impulsive behavior. While several risk factors characterize disordered gambling among adolescents, the extent to which these characteristics are related remains to be determined. In terms of screening for adolescent problem and pathological gambling, several instruments designed to reflect the Diagnostic and Statistical Manual of Mental Disorders diagnostic criteria for pathological gambling are available. Psychosocial approaches used to treat adult pathological gambling include Gamblers Anonymous, cognitive-behavioral therapy (CBT), and motivational enhancement therapy (MET). Among adolescents, CBT as well as an eclectic therapy have been helpful in reducing problematic gambling behavior. In terms of pharmacotherapy, three classes of psychotropic drugs have been used to treat adult pathological gambling - serotonin reuptake inhibitors, opioid antagonists, and mood stabilizers. While some of these pharmacotherapies have been efficacious in treating adult pathological gambling, additional double-blind, placebo-controlled studies are needed to determine the long-term effectiveness of these treatments. No known study has evaluated the use of psychopharmacologic agents in treating adolescent pathological gambling. Possible reasons for the lack of research on treatment for adolescent gambling disorders include lack of motivation to pursue treatment, feelings of self-control, and negative perception of therapy. Referrals from parents, teachers, and peers of adolescents, as well as community outreach programs, may be useful in successfully deriving a treatment population. Clinicians are advised to be sensitive to behavioral risk factors and to screen for disordered gambling in high risk adolescents. A combination of CBT and MET, as well as medication for any comorbid psychiatric condition, is recommended.

Efficacy of naltrexone on acetylcholine-induced alloknesis in atopic eczema

Atopic eczema (AE) is a chronically pruritic inflammatory skin disease. Although the mediators and exact mechanisms eliciting and sustaining pruritus are not completely known, AE patients in clinical trials have been shown to benefit under treatment with morphine antagonists. Naltrexone (NAL) is a relatively pure morphine antagonist that blocks the effects of opioids twice as much as naloxone. NAL exhibits minimal pharmacological activity and displaces endorphines at mu- and kappa-receptors without its own intrinsic activity. NAL's excellent oral bioavailability and linear increases in the area under plasma concentration-time curve make it ideal for use in experimental studies. We designed our present experiments similar to former experiments evaluating both peripheral cutaneous sensations and central itch procession in order to gain more information about the possible distribution of opioid receptors and their involvement in the pathophysiology of pruritus. Eleven AE patients participated in our double-blind study. Either 25 mg of NAL (Nemexin) or a placebo (PLA) was given to the participants 60 min prior to the acetylcholine (ACH) injection [intracutaneous (i.c.) injection of 0.02 ml of 0.55 M]. A PLA stimulus with buffered saline served as control on the opposite forearm. We used laser Doppler flowmetry to measure the vasomotoric changes after ACH injection and recorded the duration and intensity of itch with a visual analogue scale (VAS). Following the evaluation of wheal and flare sensation, we obtained the area of itchy skin around the injection site (alloknesis) by gently stroking the surrounding skin with a brush in the centripetal direction towards the injection site. The results were planimetrically evaluated. Oral NAL reduced the perifocal itch significantly (P < 0.009). In four of our observations the area of alloknesis completely disappeared. Itch duration was reduced by 20 s and the intensity of itch was diminished, yet not significantly. NAL had no significant effects on cholinergic vasoreactions measured by the laser Doppler (P > 0.50) and especially failed to decrease the initial flux response, which is a typical sign of an altered vascular reaction (P > 0.25). The decrease of wheal (P = 0.008) and flare (P = 0.01) extension indicates an appropriate dosage of our treatment for this experiment. The most significant effects of NAL were observed in parameters of itch processing such as alloknesis (P = 0.009) and flare extension (P = 0.01). Therefore we favour the concept that NAL might have a stronger impact on central nervous mechanisms than on peripheral nociceptive structures.

Bulimia in children and adolescents

Although there have been many recent advances in research, much work remains to be done in the area of child and adolescent eating disorders. More data are needed regarding the normal development of eating behavior, resilience and risk factors for eating pathology, and treatment studies in children and adolescents. The best studied areas include epidemiology, short-term treatment for bulimia nervosa (BN), and outcome in anorexia nervosa. A case report of the single blind use of repetitive transcranial magnetic stimulation in a patient with BN has been reported, but its safe use in children and adolescents remains to be established.