The use of selective serotonin reuptake inhibitors in autism and related disorders

Sleep disturbances in autism spectrum disorder: Animal models, neural mechanisms, and therapeutics

Sleep is crucial for brain development. Sleep disturbances are prevalent in children with autism spectrum disorder (ASD). Strikingly, these sleep problems are positively correlated with the severity of ASD core symptoms such as deficits in social skills and stereotypic behavior, indicating that sleep problems and the behavioral characteristics of ASD may be related. In this review, we will discuss sleep disturbances in children with ASD and highlight mouse models to study sleep disturbances and behavioral phenotypes in ASD. In addition, we will review neuromodulators controlling sleep and wakefulness and how these neuromodulatory systems are disrupted in animal models and patients with ASD. Lastly, we will address how the therapeutic interventions for patients with ASD improve various aspects of sleep. Together, gaining mechanistic insights into the neural mechanisms underlying sleep disturbances in children with ASD will help us to develop better therapeutic interventions.

Psychological Comorbidities in Autism Spectrum Disorder

Autism spectrum disorder (ASD) is characterized by impairment in behavior, communication, and social interaction. Thus, accurate identification, regular behavioral and other nonmedical interventions would improve the diagnosis, management, and treatment of this condition.In this chapter, we investigate the importance of diagnosing and identifying comorbid psychiatric disorders that occur with ASD as these conditions can often complicate treatment, and failure to recognize them can result in deficits that can persist into adolescence and adulthood. In addition, we explore the impact of comprehensive psychological intervention in ASD patients with comorbid psychiatric disorders with the ultimate goal of improving overall quality of life.

Psychotropic Medication Use for Adults with Autism Spectrum Disorder who Receive Services and Supports Through Adult Developmental Disability Services in the United States

Individuals with autism spectrum disorder (ASD) have higher rates of co-occurring diagnoses and use of psychotropic medication prescriptions than people with other developmental disabilities. Few studies have examined these trends in samples of people with intellectual and developmental disabilities (IDD) with and without ASD. Using a random sample of 11,947 adult IDD service users from 25 states, co-occurring diagnoses and psychotropic medication use were compared for those with and without ASD. Regardless of diagnosis, individuals with ASD had higher percentages of psychotropic medication use. Controlling for co-occurring condition, age, gender, and ID level, a diagnosis of ASD predicted number of medications used. Further research is needed to understand why individuals with ASD are prescribed more medication, more often, than similarly functioning groups of individuals without ASD.

Pharmacological management of core and comorbid symptoms in autism-spectrum disorder

In this article we review the evidence base and practical experience supporting the use of psychopharmacological treatments for autism-spectrum disorders across the lifespan. Recent advances in knowledge are highlighted, as are the shortcomings of published data in this field. Psychosocial and educational interventions remain the core of treatment, but there is now evidence that medication management is a good option for certain domains of behaviour. We discuss the evidence in terms of symptom clusters, including the underlying social deficit of autism and common psychiatric comorbidities.

Oxidative stress, serotonergic changes and decreased ultrasonic vocalizations in a mouse model of Smith-Lemli-Opitz syndrome

Smith-Lemli-Opitz syndrome is an inherited monogenic disorder in which mutations to the 7-dehydrocholesterol (7-DHC) reductase (Dhcr7) gene lead to deficits in cholesterol synthesis. As a result, many patients suffer from gross physiological and neurological deficits. The purpose of this study was to identify a potential abnormal behavioral phenotype in a compound mutant mouse model for Smith-Lemli-Opitz disease (Dhcr7 ^Δ3-5/T93M ) to further validate the model and to provide potential targets for future therapeutic interventions. We also sought to identify some of the underlying changes in brain function that may be responsible for behavioral differences among groups. The Dhcr7 compound mutant mice were smaller than their single mutant littermates. Both single and compound heterozygous mice made fewer ultrasonic vocalizations when separated from the dam, which may suggest a communication deficit in these animals. Striking increases of the highly oxidizable 7-DHC were observed in the compound mutant mice. 7-Dehydrocholesterol is the precursor to cholesterol and builds up because of decreased function of the mutated Dhcr7 enzyme. Additionally, several differences were noted in the serotonergic system including increased expression of the serotonin transporter and increased uptake of serotonin by isolated synaptosomes. We propose that changes to the oxidative environment during development can have a significant impact on the development of serotonergic function and that this contributes to behavioral differences observed in the mutant mice.

Risk Factors for Depression in Children and Adolescents with High Functioning Autism Spectrum Disorders

The objective of our study was to examine, discuss, and provide proposals on diagnostic comorbidity of depression in children and adolescents with high functioning autism spectrum disorder (HFASD) in the following aspects. (1) Prevalence. It was concluded that there are an elevated depression rate and the need for longitudinal studies to determine prevalence and incidence based on functioning level, autistic symptoms, gender, age, type of depression, prognosis, duration, and treatment. (2) Explicative Hypotheses and Vulnerability. The factors that present the greatest specific risk are higher cognitive functioning, self-awareness of deficit, capacity for introspection, stressful life events, adolescence, quality of social relationships, and alexithymia. (3) Risk of Suicide. The need for control and detection of suicidal tendencies and bullying is emphasised. (4) Depressive Symptoms. Indicators for early detection are proposed and their overlap with HFASD is analysed, examining the assessment techniques used and arguing that specific adapted tests are needed.

Pharmacogenomic medicine in autism: challenges and opportunities

Autism spectrum disorder (ASD) affects 1 in 68 children in the US and is distinguished by core deficits in social interactions. Developing pharmacologic treatments for ASD is complicated by clinical and genetic heterogeneity. Although pharmacological treatments have not been shown to be effective in treating the core symptoms of ASD (i.e., social deficits), there is evidence that the burden of emotional and behavioral problems can be reduced with pharmacotherapy. Numerous randomized clinical trials of treatments for the core ASD deficits have been conducted; however, most have provided inconclusive results due to the substantial variation in treatment response. Variation also exists in the considerable metabolic side effects of many of the current treatments. Some of this variation may be explained by differences in the underlying genetic pathways. Exploiting the link between genetic heterogeneity and clinical variation associated with behavioral problems may provide an opportunity for targeted treatment of ASD. In this review, we summarize the recent findings from pharmacogenomics studies of ASD and suggest further how understanding how genetic liability modifies the effect of drugs may present an opportunity to address the challenges of personalized medicine in autism.

Identifying individual differences of fluoxetine response in juvenile rhesus monkeys by metabolite profiling

Fluoxetine is the only psychopharmacological agent approved for depression by the US Food and Drug Administration for children and is commonly used therapeutically in a variety of neurodevelopmental disorders. Therapeutic response shows high individual variability, and severe side effects have been observed. In the current study we set out to identify biomarkers of response to fluoxetine as well as biomarkers that correlate with impulsivity, a measure of reward delay behavior and potential side effect of the drug, in juvenile male rhesus monkeys. The study group was also genotyped for polymorphisms of monoamine oxidase A (MAOA), a gene that has been associated with psychiatric disorders. We used peripheral metabolite profiling of blood and cerebrospinal fluid (CSF) from animals treated daily with fluoxetine or vehicle for one year. Fluoxetine response metabolite profiles and metabolite/reward delay behavior associations were evaluated using multivariate analysis. Our analyses identified a set of plasma and CSF metabolites that distinguish fluoxetine- from vehicle-treated animals and metabolites that correlate with impulsivity. Some metabolites displayed an interaction between fluoxetine and MAOA genotype. The identified metabolite biomarkers belong to pathways that have important functions in central nervous system physiology. Biomarkers of response to fluoxetine in the normally functioning brain of juvenile nonhuman primates may aid in finding predictors of response to treatment in young psychiatric populations and in progress toward the realization of a precision medicine approach in the area of neurodevelopmental disorders.

An Exploratory Survey for Understanding Perceptions, Knowledge and Educational Needs of General Practitioners (GSs) Regarding Autistic Disorders in New South Wales (NSW), Australia

AIM

A survey was conducted to ascertain General Practitioners (GPs') perceptions, knowledge and educational needs regarding autistic disorders in childhood.

METHODS

A concurrent mixed method approach was used for data collection and analysis. Exploratory factor analysis (EFA) of the data was done and groups were compared using appropriate statistical tests.

RESULTS

There was more response from female GPs, Australian medical graduates and those with an interest in mental and /or child health. Variability was noted in how GPs perceived their competence and knowledge of autistic disorders. About 60% correctly believed that an early-individualised treatment programme was evidence based. Knowledge was inversely related to the number of years in practice and enhanced by personal involvement with children of these disorders and awareness of community resources. Parallel analysis of knowledge scale revealed a "general knowledge" dimension loading items helpful for early identification and referral and a "surveillance" dimension helpful for ongoing involvement of GPs for management of children with ASDs.

CONCLUSIONS

Although further development and refinement of knowledge questionnaire using these dimensions for primary care physicians are needed these are relevant target areas for education.

Utilization patterns of conventional and complementary/alternative treatments in children with autism spectrum disorders and developmental disabilities in a population-based study

OBJECTIVE

To compare the utilization of conventional treatments and utilization of complementary and alternative medicine in preschoolers with autism spectrum disorders (ASD) and other developmental disabilities (DD).

METHODS

Participants were 578 children who were part of an ongoing population-based, case-control study of 2- to 5-year olds with ASD, DD, and the general population. Parents completed an interview on past and current services.

RESULTS

Four hundred fifty-three children with ASD and 125 DD children were included. ASD families received more hours of conventional services compared with DD families (17.8 vs 11; p < .001). The use of psychotropic medications was low in both groups (approximately 3%). Overall, complementary and alternative medicine (CAM) use was not significantly different in ASD (39%) versus DD (30%). Hispanic families in both groups used CAM less often than non-Hispanic families. Variables such as level of function, immunization status, and the presence of an identified neurogenetic disorder were not predictive of CAM use. A higher level of parental education was associated with an increased CAM use in ASD and DD. Families who used >20 hours per week of conventional services were more likely to use CAM, including potentially unsafe or disproven CAM. Underimmunized children were marginally more likely to use CAM but not more likely to have received potentially unsafe or disproven CAM.

CONCLUSION

Use of CAM is common in families of young children with neurodevelopmental disorders, and it is predicted by higher parental education and non-Hispanic ethnicity but not developmental characteristics. Further research should address how health care providers can support families in making decisions about CAM use.

[Pharmacological treatments in patients with pervasive developmental disorders: A review]

BACKGROUND

Pervasive developmental disorders (PDD) are neurodevelepmental disorders that are characterized by severe deficits in socialisation and communication, and the existence of repetitive and stereotyped interests and behaviours. It is estimated more than 60/100,000 children are suffering from PDD. Comorbid disorders are common in people with PDD, including intellectual deficiency, symptoms of attention deficit-hyperactivity, aggression and disruption, and pervasive repetitive behaviours or thoughts. These symptoms have a negative impact on the outcome and quality of life of the patients and their caregivers. The first-line management of comorbid disorders in PDD is behavioural intervention, but sometimes this is not sufficient, and the use of pharmacological treatment is needed.

METHOD

We conducted a review of studies of medical treatments used in patients with PDD to establish which treatments show good evidence of efficacy in PDD. We used the Medline database and the following keywords "pervasive development disorders" or "autism spectrum disorders" or "autistic disorder" and "therapy" or "treatment".

RESULTS

The treatments that showed the best efficacy on irritability in well-designed studies are second generation antipsychotics, risperidone and aripiprazole. Some studies indicate that haloperidol is efficient as well, but the very high frequency of extra-pyramidal effects limits its use. Methylphenidate has shown some efficacy on impulsivity and hyperactivity in randomised placebo-controlled studies. First data concerning atomoxetine are promising but better-designed studies are needed. Selective serotonin re-uptake inhibitors: fluvoxamine and fluoxetine have shown some efficacy in the treatment of serious and pervasive repetitive behaviours. Alpha-adrenergic treatments, clonidine and guanfacine, can help in the management of disruptive behaviours in patients with PDD. Data concerning naltrexone are contradictory, indeed many case reports of its efficacy on aggressive (mostly auto-aggressive) behaviours are reported in the literature, but well-designed studies do not find any improvement in patients treated with naltrexone compared with patients treated with placebo. First data concerning ocytocin are promising, indeed, if they were to be confirmed, that would be the first treatment efficient on the core symptoms of PDD.

Pharmacotherapy for the core symptoms in autistic disorder: current status of the research

The current review covers extant literature on pharmacotherapy for core symptoms of autism. The core symptoms of autism include impairments in social interaction and communication, as well as the presence of restricted and repetitive behaviors. There are no known efficacious treatments for the core social symptoms, although effects on repetitive behaviors are indicated with some data. While studies of fenfluramine, secretin, opiates, and mood stabilizers generally find no effect, mixed results suggest more research is needed on antidepressants and atypical antipsychotics. Newer lines of research, including cholinergic and glutamatergic agents and oxytocin, will be of considerable interest in the future. However, research on the treatment of core symptoms is plagued by limitations in study design, statistical power, and other issues inherent to the study of treatments for autism (e.g., heterogeneity of the disorder) that continue to prevent the elucidation of efficacious treatments.

Reduced serotonin receptor subtypes in a limbic and a neocortical region in autism

Autism is a behaviorally defined, neurological disorder with symptom onset before the age of 3. Abnormalities in social-emotional behaviors are a core deficit in autism, and are characterized by impaired reciprocal-social interaction, lack of facial expressions, and the inability to recognize familiar faces. The posterior cingulate cortex (PCC) and fusiform gyrus (FG) are two regions within an extensive limbic-cortical network that contribute to social-emotional behaviors. Evidence indicates that changes in brains of individuals with autism begin prenatally. Serotonin (5-HT) is one of the earliest expressed neurotransmitters, and plays an important role in synaptogenesis, neurite outgrowth, and neuronal migration. Abnormalities in 5-HT systems have been implicated in several psychiatric disorders, including autism, as evidenced by immunology, imaging, genetics, pharmacotherapy, and neuropathology. Although information is known regarding peripheral 5-HT in autism, there is emerging evidence that 5-HT systems in the central nervous system, including various 5-HT receptor subtypes and transporters, are affected in autism. The present study demonstrated significant reductions in 5-HT1A receptor-binding density in superficial and deep layers of the PCC and FG, and in the density of 5-HT(2A) receptors in superficial layers of the PCC and FG. A significant reduction in the density of serotonin transporters (5-HTT) was also found in the deep layers of the FG, but normal levels were demonstrated in both layers of the PCC and superficial layers of the FG. This study provides potential substrates for decreased 5-HT modulation/innervation in the autism brain, and implicate two 5-HT receptor subtypes as potential neuromarkers for novel or existing pharmacotherapies.

Mice genetically depleted of brain serotonin display social impairments, communication deficits and repetitive behaviors: possible relevance to autism

Autism is a complex neurodevelopmental disorder characterized by impaired reciprocal social interaction, communication deficits and repetitive behaviors. A very large number of genes have been linked to autism, many of which encode proteins involved in the development and function of synaptic circuitry. However, the manner in which these mutated genes might participate, either individually or together, to cause autism is not understood. One factor known to exert extremely broad influence on brain development and network formation, and which has been linked to autism, is the neurotransmitter serotonin. Unfortunately, very little is known about how alterations in serotonin neuronal function might contribute to autism. To test the hypothesis that serotonin dysfunction can contribute to the core symptoms of autism, we analyzed mice lacking brain serotonin (via a null mutation in the gene for tryptophan hydroxylase 2 (TPH2)) for behaviors that are relevant to this disorder. Mice lacking brain serotonin (TPH2-/-) showed substantial deficits in numerous validated tests of social interaction and communication. These mice also display highly repetitive and compulsive behaviors. Newborn TPH2-/- mutant mice show delays in the expression of key developmental milestones and their diminished preference for maternal scents over the scent of an unrelated female is a forerunner of more severe socialization deficits that emerge in weanlings and persist into adulthood. Taken together, these results indicate that a hypo-serotonin condition can lead to behavioral traits that are highly characteristic of autism. Our findings should stimulate new studies that focus on determining how brain hyposerotonemia during critical neurodevelopmental periods can alter the maturation of synaptic circuits known to be mis-wired in autism and how prevention of such deficits might prevent this disorder.

Use of psychotropic medication in children and adolescents with autism spectrum disorders

OBJECTIVES

The goal of this study was to examine rates of psychotropic medication use and identify associated child and family characteristics among children and adolescents with autism spectrum disorder (ASD) enrolled in an autism registry maintained by the Autism Treatment Network (ATN).

METHODS

The sample, derived from the ATN registry, consists of 2853 children aged 2 to 17 years with diagnoses of ASD supported by Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and the Autism Diagnostic Observation Schedule with available data on medication use. As part of initial enrollment in the registry, parents completed questionnaires on current psychotropic medication use, psychiatric and medical conditions, and demographics.

RESULTS

Of the 2853 children, 763 (27%) were taking ≥ 1 psychotropic medication; 15% were prescribed 1 medication, 7.4% received 2 medications, and 4.5% received ≥ 3. Among children aged 3 to 5 years, 11% were taking ≥ 1 psychotropic medication; among 6- to 11-year-old children, 46%; and 66% of adolescents aged 12 to 17 years were taking at ≥ 1 psychotropic medication. A parent report of comorbid diagnosis of attention-deficit/hyperactivity disorder, bipolar disorder, obsessive-compulsive disorder, depression, or anxiety was associated with a high rate of use, with 80% receiving ≥ 1 psychotropic medication. Only 15% of children with no comorbid psychiatric disorder were taking psychotropic medication. Psychotropic medication use was also related to sleep and gastrointestinal problems.

CONCLUSIONS

The prescription of psychotropic medications in this registry sample is highly related to comorbid psychiatric disorder. Other factors associated with use include medical comorbidities, race, ethnicity, and older age.

Early intervention combined with targeted treatment promotes cognitive and behavioral improvements in young children with fragile x syndrome

Fragile X syndrome (FXS) is the most common inherited cause of intellectual disability due to an expansion in the full mutation range (>200 CGG repeats) of the promoter region of the FMR1 gene leading to gene silencing. Lack of FMRP, a critical protein for dendritic spine formation and maturation, will cause FXS. Early environmental enrichment combined with pharmacological intervention has been proven to rescue dendritic spine abnormalities in the animal model of FXS. Here we report on 2 young children with FXS who were treated early with a combination of targeted treatment and intensive educational interventions leading to improvement in their cognition and behavior and a normal IQ.

Differences in BTBR T+ tf/J and C57BL/6J mice on probabilistic reversal learning and stereotyped behaviors

Autism spectrum disorders (ASD) represent a class of neurodevelopmental disorders characterized by impairments in social interaction, verbal and non-verbal communication, as well as restricted interests and repetitive behavior. This latter class of symptoms often includes features such as compulsive behaviors and resistance to change. The BTBR T+ tf/J mouse strain has been used as an animal model to investigate the social communication and restricted interest features in ASD. Less is known about whether this mouse strain models cognitive flexibility deficits also observed in ASD. The present experiment investigated performance of BTBR T+ tf/J and C57BL/6J on two different spatial reversal learning tests (100% accurate feedback and 80/20 probabilistic feedback), as well as marble burying and grooming behavior. BTBR T+ tf/J and C57BL/6J mice exhibited similar performance on acquisition and reversal learning with 100% accurate feedback. BTBR T+ tf/J mice were impaired in probabilistic reversal learning compared to that of C57BL/6J mice. BTBR T+ tf/J mice also displayed increased stereotyped repetitive behaviors compared to that of C57BL/6J mice as shown by increased marble burying and grooming behavior. The present findings indicate that BTBR T+ tf/J mice exhibit similar features related to "insistence on sameness" in ASD that include not only stereotyped repetitive behaviors, but also alterations in behavioral flexibility. Thus, BTBR T+ tf/J mice can serve as a model to understand the neural mechanisms underlying alterations in behavioral flexibility, as well as to test potential treatments in alleviating these symptoms.

Central tetrahydrobiopterin concentration in neurodevelopmental disorders

Tetrahydrobiopterin (BH₄) is a naturally occurring cofactor essential for critical metabolic pathways. Studies suggest that BH₄ supplementation may ameliorate autism symptoms; the biological mechanism for such an effect is unknown. To help understand the relation between central BH₄ concentration and systemic metabolism and to develop a biomarker of central BH₄ concentration, the relationship between cerebrospinal fluid BH₄ concentration and serum amino acids was studied. BH₄ concentration was found to be distributed in two groups, a lower and higher BH₄ concentration group. Two serum amino acids, citrulline and methionine, differentiated these groups, and the ratio of serum citrulline-to-methionine was found to correlate with the cerebrospinal fluid BH₄ concentration (r = −0.67, p < 0.05). Both citrulline and methionine are substrates in inflammation and oxidative stress pathways – two pathways that utilize BH₄ and are abnormally activated in autism. These data suggests that central BH₄ concentration may be related to systemic inflammation and oxidative stress pathways.

Tetrahydrobiopterin as a novel therapeutic intervention for autism

Tetrahydrobiopterin (BH(4)) is an essential cofactor for several critical metabolic pathways that have been reported to be abnormal in autism spectrum disorder (ASD). In addition, the cerebrospinal fluid concentration of BH(4) is reported to be depressed in children with ASD. Over the past 25 years, several clinical trials have suggested that treatment with BH(4) improves ASD symptomatology in some individuals. Two ongoing clinical protocols may help further define the efficacy of BH(4) treatment in children with ASD. First, children with ASD who had low concentrations of cerebrospinal fluid or urine pterins were treated in an open-label manner with 20 mg/kg per day of BH(4). The majority of children (63%) responded positively to treatment, with minimal adverse events (AEs). Second, a double-blind placebo-controlled study examining the efficacy of 20 mg/kg per day of BH(4) treatment in children with ASD is currently underway. Safety studies from the commercially available forms of BH(4) document the low incidence of AEs, particularly serious AEs. Studies have also documented the ability of BH(4) to cross the blood-brain barrier. Based on the importance of BH(4) in neurodevelopmental metabolic pathways, the safety of BH(4) treatment, and the evidence for a therapeutic benefit of BH(4) treatment in children with ASD, we conclude that BH(4) represents a novel therapy for ASD, one that may gain wider use after further clinical studies have established efficacy and treatment guidelines.

Complementary and alternative medicine in autism: an evidence-based approach to negotiating safe and efficacious interventions with families

This review focuses on helping clinicians identify resources and develop strategies they may use to effectively negotiate safe and effective use of complementary and alternative medicine (CAM) treatments with families of children with autism spectrum disorders (ASD), as well as other neurodevelopmental disorders. Since new types of CAM continue to be introduced into the autism community, emphasis is placed on providing clinicians with tools to help families negotiate the myriad of available treatments and make decisions based on current safety and efficacy data, while remaining mindful of the reasons families may be considering these treatments. We familiarize readers with high-quality, evidence-based resources that providers and families may use to ascertain current information about specific types of CAM, verify the content of biologically-based treatments, identify ongoing CAM research and obtain toolkits designed to help healthcare providers raise the topic of CAM usage and facilitate disclosure and discussion of CAM use with patients and their families.

A pharmacogenetic study of escitalopram in autism spectrum disorders

OBJECTIVE

To determine the effect of serotonin transporter polymorphism promoter region (5-HTTPLR) genotypic variation (low, intermediate, and high expression groups) on response to escitalopram treatment of children and adolescents with autism spectrum disorders (ASDs).

METHOD

The study used a forced titration, open label design, with genotype blind until study completion. Participants were children and adolescents aged 4-17 years of age with a confirmed ASD (autistic disorder, Asperger's disorder, or pervasive developmental disorder, not otherwise specified).

RESULTS

There was an interaction between genotype group and time on the Aberrant Behavior Checklist (ABC) Irritability Subscale (primary outcome variable) (linear maximum marginal likelihood estimation=-4.84, Z=-2.89, SE=1.67, P=0.004). Examination of baseline to last visit revealed that a genotype grouping based on a previous study of platelet 5-HT uptake revealed less response in the genotype group that had S/S genotype for 5-HTTLPR and did not have a diplotype in intron 1 previously shown to be associated with increased platelet 5-HT uptake.

CONCLUSION

This genotype-blind, prospective pharmacogenetic study found the group of subjects with associated with the lowest platelet 5-HT uptake from previous study had the smallest reduction in ABC-Irritability scores after open label treatment with escitalopram. Replication is necessary to confirm these findings.

Review of the evidence for treatment of children with autism with selective serotonin reuptake inhibitors

PURPOSE

To review the potential role of serotonin dysregulation in autism and the efficacy of selective serotonin reuptake inhibitors (SSRIs) in treating core deficits and associated symptoms of autism in children. The literature was searched for reports of SSRI use in children with autism. Data are presented from prospective clinical trials that evaluated treatment outcomes.

CONCLUSIONS

Some SSRIs show moderate success in managing specific behaviors. Only fluoxetine shows evidence of decreasing global autism severity.

PRACTICE IMPLICATION

Definitive conclusions concerning selection criteria, dosage, safety, and efficacy cannot be drawn given the current state of evidence.

A longitudinal investigation of psychotropic and non-psychotropic medication use among adolescents and adults with autism spectrum disorders

Medication use was examined in 286 adolescents and adults with ASD over a 4.5 year period. A total of 70% were taking a psychotropic or non-psychotropic medication at the beginning of the study. Both the number of psychotropic and non-psychotropic medications taken, and the proportion of individuals taking these medications, increased significantly over the study period, with 81% taking at least one medication 4.5 years later. Our findings suggested a high likelihood of staying medicated over time. Thus, adolescents and adults with ASD are a highly and increasingly medicated population.

Atomoxetine for the treatment of attention-deficit/hyperactivity disorder in children and adolescents: a review

OBJECTIVE

This review examines and summarizes the pharmacodynamic and pharmacokinetic properties, short- and longer-term efficacy, the moderating effect of comorbid disorders, as well as short- and long-term safety and tolerability of atomoxetine for the treatment of pediatric attention-deficit/hyperactivity disorder (ADHD).

METHODS

A systematic literature search was performed to review the extant literature on articles pertaining to the pharmacological treatment with atomoxetine in pediatric and/or adolescent ADHD.

RESULTS

There is an extensive literature on atomoxetine; over 4000 children have participated in clinical trials of atomoxetine, demonstrating its short- and longer-term efficacy. In addition, studies have examined the moderating effect of comorbid disorders on atomoxetine response, as well as atomoxetine's therapeutic potential for other psychiatric conditions. Short- and longer-term safety and tolerability continue to be reported.

CONCLUSIONS

Atomoxetine is indicated for both acute and maintenance/extended treatment of pediatric ADHD. Clinicians and families must be familiar with atomoxetine's evidence base, including its profile of clinical response and its possible effectiveness in the presence of comorbidity.

Pharmacologic treatment for the core deficits and associated symptoms of autism in children

Autism is a neurodevelopmental condition affecting 1 out of 160 children in the United States today. Only risperidone has Food and Drug Administration approval for the pharmacologic management of autism in children. However, health care providers may prescribe other drugs used off-label to assist autistic children and their families with the core deficits and associated behaviors of this condition. Evidence for the use of these medications will be discussed in this continuing education offering. Meta analyses, randomized clinical trials, and other prospective experimental studies of pharmacotherapy conducted in the United States in the past 10 years in children between the ages of 5 and 15 years were reviewed. The results support moderate success in treating the associated behaviors of autism and minimal success in treating core deficits across all drug classes. Preliminary evidence demonstrates possible uses for atypical antipsychotic agents, selective-serotonin reuptake inhibitors, stimulants, and N-methyl-D-aspirate receptor antagonists in decreasing the core behaviors and associated symptoms of autism. More studies and longer periods of follow-up are needed before definitive guidelines can be suggested.

DEVELOPING DRUGS FOR CORE SOCIAL AND COMMUNICATION IMPAIRMENT IN AUTISM

There are many challenges to studying drug effects on core social and language impairment in autism. Drugs such as fenfluramine, naltrexone, and secretin do not appear to be efficacious for these core symptoms. Risperidone has led to improvement in some aspects of social relatedness when used to treat irritability in autism. More research is needed on the utility of selective serotonin reuptake inhibitors, cholinergic drugs, glutamatergic drugs, and oxytocin for core autistic symptoms.

Psychopharmacologic interventions for repetitive behaviors in autism spectrum disorders

This article provides an overview of psychopharmacological treatments for repetitive behaviors in autism spectrum disorders (ASDs) in the context of current conceptualizations of this understudied core symptom domain. The available literature on the widely used selective serotonin reuptake inhibitors (SSRIs), including fluvoxamine, fluoxetine, citalopram, escitalopram, and sertraline, are reviewed. In addition to SSRIs, research on effects of other pharmacologic interventions such as divalproex sodium, risperidone, and the neuropeptide oxytocin are presented. To date, data are mixed for interventions commonly prescribed in clinical practice and suggest several areas of investigation in advancing research on the medication management of repetitive behaviors.

The neurobiology of autism

Improving clinical tests are allowing us to more precisely classify autism spectrum disorders and diagnose them at earlier ages. This raises the possibility of earlier and potentially more effective therapeutic interventions. To fully capitalize on this opportunity, however, will require better understanding of the neurobiological changes underlying this devastating group of developmental disorders. It is becoming clear that the normal trajectory of neurodevelopment is altered in autism, with aberrations in brain growth, neuronal patterning and cortical connectivity. Changes to the structure and function of synapses and dendrites have also been strongly implicated in the pathology of autism by morphological, genetic and animal modeling studies. Finally, environmental factors are likely to interact with the underlying genetic profile, and foster the clinical heterogeneity seen in autism spectrum disorders. In this review we attempt to link the molecular pathways altered in autism to the neurodevelopmental and clinical changes that characterize the disease. We focus on signaling molecules such as neurotrophin, Reelin, PTEN and hepatocyte growth factor, neurotransmitters such as serotonin and glutamate, and synaptic proteins such as neurexin, SHANK and neuroligin. We also discuss evidence implicating oxidative stress, neuroglial activation and neuroimmunity in autism.

Management of children with autism spectrum disorders

Pediatricians have an important role not only in early recognition and evaluation of autism spectrum disorders but also in chronic management of these disorders. The primary goals of treatment are to maximize the child's ultimate functional independence and quality of life by minimizing the core autism spectrum disorder features, facilitating development and learning, promoting socialization, reducing maladaptive behaviors, and educating and supporting families. To assist pediatricians in educating families and guiding them toward empirically supported interventions for their children, this report reviews the educational strategies and associated therapies that are the primary treatments for children with autism spectrum disorders. Optimization of health care is likely to have a positive effect on habilitative progress, functional outcome, and quality of life; therefore, important issues, such as management of associated medical problems, pharmacologic and nonpharmacologic intervention for challenging behaviors or coexisting mental health conditions, and use of complementary and alternative medical treatments, are also addressed.

The status of pharmacotherapy for autism spectrum disorders

The use of pharmacologic agents as a component of treatment for children and adults with autism spectrum disorders is common and a substantial body of literature describing controlled and open-label clinical trials now exists to guide clinical practice. Empiric evidence of efficacy of risperidone, methylphenidate and some selective serotonin re-uptake inhibitors for maladaptive behaviors commonly associated with autism spectrum disorders has increased substantially in recent years. Preliminary controlled trials of valproate, atomoxetine, alpha-2 adrenergic agonists and olanzapine are promising. In addition to traditional psychotropic medications, investigators have examined the potential role of a variety of agents with glutamatergic or cholinergic mechanisms, and the results warrant further investigation. Although psychotropic medications are effective in treating some important associated behaviors, evidence of significant impact on the core features of autism spectrum disorders is very limited.