Brief Report: Self-Reported Medication Use in Individuals Diagnosed with Autism Spectrum Disorder in Adulthood: A U.S. Clinic Sample from 2012 to 2022

PURPOSE

As the understanding of autism spectrum disorder (ASD) across the lifespan has increased, so has the number of individuals being identified with ASD for the first time in adulthood. Understanding co-occurring psychiatric conditions in this subset of the ASD population is a growing focus of research; however, little is known about the rate at which psychiatric medications are prescribed to adults with a first-time diagnosis of ASD. The purpose of this study was to examine self-reported medication use in persons diagnosed with ASD in adulthood in a clinic sample (2012-2022) in the United States.

METHODS

The present study was a retrospective record review. Participants (n = 281) were drawn from an outpatient clinic specializing in the diagnosis of ASD in adults. Participants self-reported previous and current psychiatric medication prescription using a medication checklist.

RESULTS

Approximately 50% of participants self-reported being prescribed at least one psychiatric medication at the time of their initial evaluation appointment. The most commonly prescribed psychiatric medications were antidepressants (23.8%), followed by stimulants (16.7%).

CONCLUSION

Similar to individuals diagnosed with ASD in childhood, those identified with ASD for the first time in adulthood are prescribed psychiatric medication at a much higher rate than their same-age non-autistic peers. These results can inform future research and practice for improving outcomes for autistic adults, particularly those who were undiagnosed for much of their lives.

Metabolomic profiles in Jamaican children with and without autism spectrum disorder

Background

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition with a wide range of behavioral and cognitive impairments. While genetic and environmental factors are known to contribute to its etiology, the underlying metabolic perturbations associated with ASD which can potentially connect genetic and environmental factors, remain poorly understood. Therefore, we conducted a metabolomic case-control study and performed a comprehensive analysis to identify significant alterations in metabolite profiles between children with ASD and typically developing (TD) controls.

Objective

To elucidate potential metabolomic signatures associated with ASD in children and identify specific metabolites that may serve as biomarkers for the disorder.

Methods

We conducted metabolomic profiling on plasma samples from participants in the second phase of Epidemiological Research on Autism in Jamaica (ERAJ-2), which was a 1:1 age (±6 months)-and sex-matched cohort of 200 children with ASD and 200 TD controls (2-8 years old). Using high-throughput liquid chromatography-mass spectrometry techniques, we performed a targeted metabolite analysis, encompassing amino acids, lipids, carbohydrates, and other key metabolic compounds. After quality control and imputation of missing values, we performed univariable and multivariable analysis using normalized metabolites while adjusting for covariates, age, sex, socioeconomic status, and child's parish of birth.

Results

Our findings revealed unique metabolic patterns in children with ASD for four metabolites compared to TD controls. Notably, three of these metabolites were fatty acids, including myristoleic acid, eicosatetraenoic acid, and octadecenoic acid. Additionally, the amino acid sarcosine exhibited a significant association with ASD.

Conclusions

These findings highlight the role of metabolites in the etiology of ASD and suggest opportunities for the development of targeted interventions.

Additive or Interactive Associations of Food Allergies with Glutathione S-Transferase Genes in Relation to ASD and ASD Severity in Jamaican Children

To investigate additive and interactive associations of food allergies with three glutathione S-transferase (GST) genes in relation to ASD and ASD severity in Jamaican children. Using data from 344 1:1 age- and sex-matched ASD cases and typically developing controls, we assessed additive and interactive associations of food allergies with polymorphisms in GST genes (GSTM1, GSTP1 and GSTT1) in relation to ASD by applying conditional logistic regression models, and in relation to ASD severity in ASD cases as measured by the Autism Diagnostic Observation Schedule-2nd Edition (ADOS-2) total and domains specific comparison scores (CSs) by fitting general linear models. Although food allergies and GST genes were not associated with ASD, ASD cases allergic to non-dairy food had higher mean ADOS-2 Restricted and Repetitive Behaviors (RRB) CS (8.8 vs. 8.0, P = 0.04). In addition, allergy to dairy was associated with higher mean RRB CS only among ASD cases with GSTT1 DD genotype (9.9 vs. 7.8, P < 0.01, interaction P = 0.01), and GSTP1 Val/Val genotype under a recessive genetic model (9.8 vs. 7.8, P = 0.02, interaction P = 0.06). Our findings are consistent with the role for GST genes in ASD and food allergies, though require replication in other populations.

What is a Good Mother of Children with Autism? A Cross-Cultural Comparison Between the U.S. and Japan

This study compared the characteristics of 'good mothers' of children with ASD (Autism Spectrum Disorder) as perceived by mothers of children with ASD in two countries-the U.S. and Japan. Grounded in the theory of culturally-influenced construal of the self, we hypothesized that U.S. mothers would prioritize fostering self-reliance and advocating for their child's well-being while Japanese mothers would prioritize maintaining close and harmonious relationships with their child. We conducted semi-structured interviews with 52 U.S. and 51 Japanese mothers of children with ASD about the characteristics of a good mother of a child with ASD (GMA) and characteristics of a good mother in general (GMG) and compared the frequencies of 'good mother' categories emerging from thematic analysis. Mothers of children with ASD in both countries viewed guiding children as the most important characteristic for both GMG and GMA. As hypothesized, U.S mothers tended to emphasize a mother's active role in advocating for her children, getting her child services and intervention, and educating herself about ASD. In contrast, Japanese mothers tended to value a mother's ability to accept her child, know her child well, and provide adequate support for her child based on a child-oriented perspective. The mother's role of advocating for her child and educating herself emerged more frequently in responses regarding GMA than GMG in the U.S. sample. The study revealed cultural differences in characterization of GMA, suggesting that more indirect models of instruction may be effective for different cultural groups.

Factors associated with blood mercury concentrations and their interactions with three glutathione S-transferase genes (GSTT1, GSTM1, and GSTP1): an exposure assessment study of typically developing Jamaican children

BACKGROUND

Jamaican soil is abundant in heavy metals including mercury (Hg). Due to availability and ease of access, fish is a traditional dietary component in Jamaica and a significant source of Hg exposure. Mercury is a xenobiotic and known neuro-toxicant that affects children's neurodevelopment. Human glutathione S-transferase (GST) genes, including GSTT1, GSTM1, and GSTP1, affect Hg conjugation and elimination mechanisms.

METHODS

In this exposure assessment study we used data from 375 typically developing (TD) 2-8-year-old Jamaican children to explore the association between environmental Hg exposure, GST genes, and their interaction effects on blood Hg concentrations (BHgCs). We used multivariable general linear models (GLMs).

RESULTS

We identified the child's age, consumption of saltwater fish, canned fish (sardine, mackerel), string beans, grain, and starches (pasta, macaroni, noodles) as the environmental factors significantly associated with BHgCs (all P < 0.05). A significant interaction between consumption of canned fish (sardine, mackerel) and GSTP1 in relation to BHgC using either a co-dominant or recessive genetic model (overall interaction P = 0.01 and P < 0.01, respectively) indicated that consumption of canned fish (sardine, mackerel) was significantly associated with higher mean BHgC only among children with the GSTP1 Ile105Val, Ile/Ile [Ratio of mean Hg (95% CI) = 1.59 (1.09, 2.32), P = 0.02] and Ile/Val [Ratio of mean Hg (95% CI) = 1.46 (1.12, 1.91), P = 0.01] genotypes.

CONCLUSIONS

Since this is the first study from Jamaica to report these findings, replication in other populations is recommended.

Executive Function in Autism: Association with ADHD and ASD Symptoms

There is substantial comorbidity between autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD), and there are well-documented executive functioning (EF) deficits in both populations. An important question concerns whether EF deficits in children with ASD are related to severity of ASD, ADHD, or both. We examined ADHD and ASD symptoms in relation to ratings of EF in the home and classroom. The sample comprised 64 children (55 males) diagnosed with ASD (mean age = 9.26 years; mean FSIQ = 92). Analyses indicated that parent and teacher ratings of EF (except Shift and Emotional Control) were consistently related to ADHD symptom severity, but not to ASD severity. Thus, functioning in the domains of Shift and Emotional control appear relatively spared, whereas performance in all other EF was impaired in relation to ADHD symptoms.

Interactions between Environmental Factors and Glutathione S-Transferase (GST) Genes with Respect to Detectable Blood Aluminum Concentrations in Jamaican Children

Aluminum (Al) is a metallic toxicant at high concentrations following natural or unnatural exposures. Dietary intake is considered as the main source of aluminum exposure in children. We used data from 366 typically developing (TD) children (ages 2−8 years) who participated as controls in an age- and sex-matched case−control study in Jamaica. We investigated additive and interactive associations among environmental factors and children’s genotypes for glutathione S-transferase (GST) genes (GSTT1, GSTM1, GSTP1), in relation to having a detectable blood aluminum concentration (BAlC) of >5.0 μg/L, using multivariable logistic regression models. Findings from interactive models revealed that the odds of having a detectable BAlC was significantly higher among children who ate string beans (p ≤ 0.01), whereas about 40% lower odds of having a detectable BAlC was observed in children with higher parental education level, (p = 0.02). A significant interaction between consumption of saltwater fish and GSTP1 in relation to having a detectable BAlC using either co-dominant or dominant genetic models (overall interaction p = 0.02 for both models) indicated that consumption of saltwater fish was associated with higher odds of having a detectable BAlC only among children with the GSTP1 Ile105Val Ile/Ile genotype using either co-dominant or dominant models [OR (95% CI) = 2.73 (1.07, 6.96), p = 0.04; and OR (95% CI) = 2.74 (1.08, 6.99), p = 0.03]. Since this is the first study from Jamaica that reports such findings, replication in other populations is warranted.

Correlation between concentrations of four heavy metals in cord blood and childhood blood of Jamaican children

This study investigated whether the concentrations of four metals [lead (Pb), mercury (Hg), manganese (Mn), and aluminum (Al)] are correlated in cord blood and childhood blood samples from Jamaican children. Cord blood samples were obtained from 21 pregnant women enrolled in the second Jamaican Birth Cohort Study from July 1, 2011 to September 30, 2011, and blood samples were drawn from their children who participated in a follow up study when the children were 4-8 years old. Correlations were assessed by the Pearson or the Spearman's rank correlation coefficient. The mean ages of children at the childhood visit and their mother at the child's birth were 5.5 years and 29.8 years, respectively. About 47.6% of children were male. Statistically significant correlations between cord blood and childhood blood concentrations of Pb (r_Spearman =0.45; P = 0.04) and Mn (r_Pearson=0.48; P = 0.03) were found, and these remained significant when adjusted for the child's sex, age, or both. For Al and Hg, r_Spearman=0.29 and 0.08, respectively, but the correlations were not statistically significant (both P ≥ 0.20). A significant correlation between cord blood and childhood blood Pb concentrations for children 4-8 years old has not been previously reported.

Interaction of Blood Manganese Concentrations with GSTT1 in Relation to Autism Spectrum Disorder in Jamaican Children

Using data from 266 age- and sex-matched pairs of Jamaican children with autism spectrum disorder (ASD) and typically developing (TD) controls (2-8 years), we investigated whether glutathione S-transferase theta 1 (GSTT1) modifies the association between blood manganese concentrations (BMC) and ASD. After adjusting conditional logistic regression models for socioeconomic status and the interaction between GSTT1 and GSTP1 (glutathione S-transferase pi 1), using a recessive genetic model for GSTT1 and either a co-dominant or dominant model for GSTP1, the interaction between GSTT1 and BMC was significant (P = 0.02, P = 0.01, respectively). Compared to controls, ASD cases with GSTT1-DD genotype had 4.33 and 4.34 times higher odds of BMC > 12 vs. ≤ 8.3 μg/L, respectively. Replication in other populations is warranted.

ADHD severity as a predictor of cognitive task performance in children with Autism Spectrum Disorder (ASD)

BACKGROUND

In recent years, a number of studies have begun to explore the nature of Attention-Deficit/Hyperactivity Disorder (ADHD) in children with Autism Spectrum Disorder (ASD). In this study, we examined the relationship between both symptoms of ADHD and symptoms of ASD on cognitive task performance in a sample of higher-functioning children and adolescents with ASD. Participants completed cognitive tasks tapping aspects of attention, impulsivity/inhibition, and immediate memory.

AIMS

We hypothesized that children with ASD who had higher levels of ADHD symptom severity would be at higher risk for poorer sustained attention and selective attention, greater impulsivity/disinhibition, and weaker memory.

METHODS AND PROCEDURES

The sample included 92 children (73 males) diagnosed with ASD (Mean Age = 9.41 years; Mean Full Scale IQ = 84.2).

OUTCOMES AND RESULTS

Using regression analyses, more severe ADHD symptomatology was found to be significantly related to weaker performance on tasks measuring attention, immediate memory, and response inhibition. In contrast, increasing severity of ASD symptomatology was not associated with higher risk of poorer performance on any of the cognitive tasks assessed.

CONCLUSIONS AND IMPLICATIONS

These results suggest that children with ASD who have more severe ADHD symptoms are at higher risk for impairments in tasks assessing attention, immediate memory, and response inhibition-similar to ADHD-related impairments seen in the general pediatric population. As such, clinicians should assess various aspects of cognition in pediatric patients with ASD in order to facilitate optimal interventional and educational planning.

Global vascular surgeons' experience, stressors, and coping during the coronavirus disease 2019 pandemic

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic has led to unprecedented challenges for health care systems globally. We designed and administered a global survey to examine the effects of COVID-19 on vascular surgeons and explore the COVID-19-related stressors faced, coping strategies used, and support structures available.

METHODS

The Pandemic Practice, Anxiety, Coping, and Support Survey for Vascular Surgeons was an anonymous cross-sectional survey sponsored by the Society for Vascular Surgery Wellness Task Force. The survey analysis evaluated the effects of COVID-19-related stressors on vascular surgeons measured using the Generalized Anxiety Disorder 7-item scale. The 28-item Brief Coping Orientation to Problems Experienced inventory was used to assess the active and avoidant coping strategies. Survey data were collected using REDCap (Research Electronic Data Capture) from April 14, 2020 to April 24, 2020 inclusive. Additional qualitative data were collected using open-ended questions. Univariable and multivariable analyses of the factors associated with the anxiety levels and qualitative analysis were performed.

RESULTS

A total of 1609 survey responses (70.5% male; 82.5% vascular surgeons in practice) from 58 countries (43.4% from United States; 43.4% from Brazil) were eligible for analysis. Some degree of anxiety was reported by 54.5% of the respondents, and 23.3% reported moderate or severe anxiety. Most respondents (∼60%) reported using active coping strategies and the avoidant coping strategy of "self-distraction," and 20% used other avoidant coping strategies. Multivariable analysis identified the following factors as significantly associated with increased self-reported anxiety levels: staying in a separate room at home or staying at the hospital or a hotel after work (odds ratio [OR], 1.39; 95% confidence interval [CI], 1.08-1.79), donning and doffing personal protective equipment (OR, 1.81; 95% CI, 1.41-2.33), worry about potential adverse patient outcomes due to care delay (OR, 1.47; 95% CI, 1.16-1.87), and financial concerns (OR, 1.90; 95% CI, 1.49-2.42). The factors significantly associated with decreased self-reported anxiety levels were hospital support (OR, 0.83; 95% CI, 0.76-0.91) and the use of positive reframing as an active coping strategy (OR, 0.88; 95% CI, 0.81-0.95).

CONCLUSIONS

Vascular surgeons globally have been experiencing multiple COVID-19-related stressors during this devastating crisis. These findings have highlighted the continued need for hospital systems to support their vascular surgeons and the importance of national societies to continue to invest in peer-support programs as paramount to promoting the well-being of vascular surgeons during and after the COVID-19 pandemic.

Perinatal Factors Associated with Autism Spectrum Disorder in Jamaican Children

Mode of delivery, preterm birth, and low birth weight (LBW) are hypothesized to be associated with autism spectrum disorder (ASD) in the offspring. Using data from 343 ASD cases (2-8 years) and their age- and sex-matched typically developing controls in Jamaica we investigated these hypotheses. Our statistical analyses revealed that the parish of residence could modify the association between cesarean delivery and ASD, with a difference found in this relationship in Kingston parish [matched odds ratio (MOR) (95% confidence interval (CI)) 2.30 (1.17-4.53)] and other parishes [MOR (95% CI) 0.87 (0.48-1.59)]. Although the associations of LBW and preterm birth with ASD were not significant, we observed a significant interaction between LBW and the household socioeconomic status. These findings require replication.

Interaction between a Mixture of Heavy Metals (Lead, Mercury, Arsenic, Cadmium, Manganese, Aluminum) and GSTP1, GSTT1, and GSTM1 in Relation to Autism Spectrum Disorder

BACKGROUND

Exposure to many environmental chemicals, including metals, often does not occur in isolation, hence requires assessment of the associations between exposure to mixtures of chemicals and human health.

OBJECTIVES

To investigate associations of a metal mixture of lead (Pb), mercury (Hg), arsenic (As), cadmium (Cd), manganese (Mn), and aluminum (Al) in children with autism spectrum disorder (ASD), additively or interactively with each of three glutathione S-transferase (GST) genes (GSTP1, GSTT1, and GSTM1).

METHOD

Using data from 266 case-control pairs of Jamaican children (2-8 years old), we fitted negative and positive generalized weighted quantile sum (gWQS) regression models to assess the aforementioned associations.

RESULTS

Based on additive and interactive negative gWQS models adjusted for maternal age, parental education, child's parish, and seafood consumption, we found inverse associations of the overall mixture score with ASD [MOR (95% CI): 0.70 (0.49, 0.99); P < 0.05) and [MOR (95%CI): 0.46 (0.25, 0.84); P = 0.01], respectively. In an unadjusted negative gWQS model, we found a marginally significant interaction between GSTP1 and a mixture of three metals (Pb, Hg, and Mn) (P = 0.07) while the association was no longer significant after adjustment for the same covariates (P = 0.24).

CONCLUSIONS

Differences in diet between ASD and control groups may play a role in the inverse associations we found. The possible interactive association between Mn and GSTP1 in ASD based on gWQS is consistent with our previous reports. However, possible interaction of GSTP1 with Pb and Hg in ASD requires further investigation and replication.

Effects of Extended-Release Methylphenidate Treatment on Cognitive Task Performance in Children with Autism Spectrum Disorder and Attention-Deficit/Hyperactivity Disorder

Objective: To examine the effectiveness of four doses of psychostimulant medication, combining extended-release methylphenidate (ER-MPH) in the morning with immediate-release MPH (IR-MPH) in the afternoon, on cognitive task performance. Method: The sample comprised 24 children (19 boys and 5 girls) who met the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition Text Revision (DSM-IV-TR) criteria for an autism spectrum disorder (ASD) on the Autism Diagnostic Interview-R and the Autism Diagnostic Observation Schedule, and had significant symptoms of attention-deficit/hyperactivity disorder (ADHD). This sample consisted of elementary school-age, community-based children (mean chronological age = 8.8 years, SD = 1.7; mean intelligence quotient = 85; SD = 16.8). Effects of placebo and three dose levels of ER-MPH (containing 0.21, 0.35, and 0.48 mg/kg equivalent of IR-MPH) on cognitive task performance were compared using a within-subject, crossover, placebo-controlled design. Each of the four MPH dosing regimens (placebo, low-dose MPH, medium-dose MPH, and high-dose MPH) was administered for 1 week; the dosing order was counterbalanced across children. Results: MPH treatment was associated with significant performance gains on cognitive tasks tapping sustained attention, selective attention, and impulsivity/inhibition. Dose/response was generally linear in the dose range studied, with no evidence of deterioration in performance at higher MPH doses in the dose range studied. Conclusion: The results of this study suggest that MPH formulations are associated with significant improvements on cognitive task performance in children with ASD and ADHD.

Association of Polychlorinated Biphenyls and Organochlorine Pesticides with Autism Spectrum Disorder in Jamaican Children

BACKGROUND

Polychlorinated biphenyls (PCBs) and organochlorine (OC) pesticides are suspected to play a role in autism spectrum disorder (ASD).

OBJECTIVES

To investigate associations of PCBs and OC pesticides with ASD in Jamaican children and explore possible interaction between PCBs or OC pesticides with glutathione S-transferase (GST) genes (GSTT1, GSTM1, GSTP1) in relation to ASD.

METHODS

Participants included n=169 age- and sex-matched case-control pairs of Jamaican children 2-8 years old. Socioeconomic status and food frequency data were self-reported by the parents/guardians. Blood from each participant was analyzed for 100 PCB congeners and 17 OC pesticides and genotyped for three GST genes. PCBs and OC pesticides concentrations below the limit of detection (LoD) were replaced with (LoD/√2). We used conditional logistic regression (CLR) models to assess associations of PCBs and OC pesticides with ASD, individually or interactively with GST genes (GSTT1, GSTM1, GSTP1).

RESULTS

We found inverse associations of PCB-153 [adjusted MOR (95% CI) = 0.44 (0.23-0.86)] and PCB-180 [adjusted MOR (95% CI) = 0.52 (0.28-0.95)] with ASD. When adjusted for covariates in a CLR the interaction between GSTM1 and PCB-153 became significant (P < 0.01).

DISCUSSION

Differences in diet between ASD and typically developing control groups may play a role in the observed findings of lower concentrations of PCB-153 and PCB-180 in individuals with ASD than in controls. Considering the limited sample size and high proportion of concentrations below the LoD, these results should be interpreted with caution but warrant further investigation into associations of PCBs and OC pesticides with ASD.

Maternal Exposures Associated with Autism Spectrum Disorder in Jamaican Children

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder with poorly understood etiology. Many maternal exposures during pregnancy and breastfeeding potentially interfere with neurodevelopment. Using data from two age- and sex-matched case-control studies in Jamaica (n = 298 pairs), results of conditional logistic regression analyses suggest that maternal exposures to fever or infection (matched odds ratio (MOR) = 3.12, 95% CI 1.74-5.60), physical trauma (MOR 2.02, 95% CI 1.01-4.05), and oil-based paints (MOR 1.99, 95% CI 1.14-3.46) may be associated with ASD. Additionally, maternal exposure to oil-based paints may modify the relationship between maternal exposure to pesticides and ASD, which deepens our understanding of the association between pesticides and ASD.

Concentrations of Lead, Mercury, Arsenic, Cadmium, Manganese, and Aluminum in Blood of Romanian Children Suspected of Having Autism Spectrum Disorder

Environmental exposure to lead (Pb), mercury (Hg), arsenic (As), cadmium (Cd), manganese (Mn), and aluminum (Al) has been associated with neurodevelopmental disorders including autism spectrum disorder (ASD). We conducted a pilot study during May 2015-May 2107 to estimate blood concentrations of six metals (Pb, Hg, As, Cd, Mn, and Al) and identify their associated factors for children with ASD or suspected of having ASD in Romania. Sixty children, age 2-8 years, were administered versions of ADOS or ADI-R translated from English to Romanian. After assessment, 2-3 mL of blood was obtained and analyzed for the concentrations of the six metals. The mean age of children was 51.9 months and about 90% were male. More than half (65%) of the children were born in Bucharest. Over 90% of concentrations of As and Cd were below limits of detection. Geometric mean concentrations of Pb, Mn, Al, and Hg were 1.14 μg/dL, 10.84 μg/L, 14.44 μg/L, and 0.35 μg/L, respectively. Multivariable linear regression analysis revealed that children who were female, had less educated parents, exhibited pica, and ate cold breakfast (e.g., cereal), watermelon, and lamb had significantly higher concentrations of Pb compared to their respective referent categories (all p < 0.05 except for eating lamb, which was marginally significant, p = 0.053). Although this is the first study that provides data on concentrations of the six metals for Romanian children with ASD, the findings from this study could be useful for designing future epidemiologic studies for investigating the role of these six metals in ASD in Romanian children.

A generalized weighted quantile sum approach for analyzing correlated data in the presence of interactions

A weighted quantile sum (WQS) regression has been used to assess the associations between environmental exposures and health outcomes. However, the currently available WQS approach, which is based on additive effects, does not allow exploring for potential interactions of exposures with other covariates in relation to a health outcome. In addition, the current WQS cannot account for clustering, thus it may not be valid for analysis of clustered data. We propose a generalized WQS approach that can assess interactions by estimating stratum-specific weights of exposures in a mixture, while accounting for potential clustering effect of matched pairs of cases and controls as well as censored exposure data due to being below the limits of detection. The performance of the proposed method in identifying interactions is evaluated through simulations based on various scenarios of correlation structures among the exposures and with an outcome. We also assess how well the proposed method performs in the presence of the varying levels of censoring in exposures. Our findings from the simulation study show that the proposed method outperforms the traditional WQS, as indicated by higher power of detecting interactions. We also find no strong evidence that the proposed method falsely identifies interactions when there are no true interactive effects. We demonstrate application of the proposed method to real data from the Epidemiological Research on Autism Spectrum Disorder (ASD) in Jamaica (ERAJ) by examining interactions between exposure to manganese and glutathione S-transferase family gene, GSTP1 in relation to ASD.

Interaction between manganese and GSTP1 in relation to autism spectrum disorder while controlling for exposure to mixture of lead, mercury, arsenic, and cadmium

BACKGROUND

We previously reported a significant interactive association between polymorphisms of GSTP1 and blood manganese concentrations (BMC) with autism spectrum disorder (ASD) in Jamaican children. In this paper, we investigate the same interactive association with ASD while adjusting for the mixture of four metals (lead, mercury, cadmium, and arsenic).

METHOD

We used data from 163 case-control pairs of children 2-8 years of age from our autism project in Jamaica, in which we collected blood for heavy metals analysis at enrollment. To minimize potential multicollinearity between concentrations of the four metals, we generated a mixture index using generalized weighted quantile sum regression, which was used in conditional logistic regression models to control for the four metals while assessing the interactive association between GSTP1 and BMC with ASD.

RESULTS

Similar to the findings we reported previously, we found that in co-dominant and dominant models for GSTP1, among children with the Ile/Ile genotype, those with BMC > 12μg/L had 4.6 and 4.27 times higher odds of ASD compared to those with BMC < 12μg/L (adjusted Matched Odds Ratio (MOR) = 4.6, 95% CI: 1.21 - 17.42 and adjusted MOR = 4.27, 95% CI: 1.15 - 15.85, respectively). In the co-dominant model, for children with the Ile/Val and Val/Val genotypes, the adjusted MORs were 1.26 (95% CI: 0.32, 5.01) and 0.26 (95% CI: 0.05, 1.42), respectively.

CONCLUSIONS

After adjusting for the mixture of four metals, the interactive association of BMC and GSTP1 with ASD remained significant with similar magnitude of associations. Results should be interpreted cautiously.

Parent-Reported Problematic Sleep Behaviors in Children with Comorbid Autism Spectrum Disorder and Attention-Deficit/Hyperactivity Disorder

BACKGROUND

Sleep problems are frequent and well documented in children with Autism Spectrum Disorders (ASD), children with Attention Deficit/Hyperactivity Disorder (ADHD) and children with internalizing problems, however limited work has examined sleep problems in children presenting with comorbid ASD/ADHD. In healthy children, sleep problems negatively impact social, emotional, and academic functioning. The current study sought to examine diagnostic severity as predictors of sleep problems in children with comorbid ASD/ADHD. Additionally, the association between sleep and "real-life" functional domains (i.e., intellectual functioning, academic achievement, and executive functioning) were assessed.

METHOD

Sleep, internalizing difficulties, intellectual functioning, academic achievement and executive functioning were assessed in 85 children with who carried the dual diagnoses of ASD and ADHD.

RESULTS

Internalizing difficulties, rather than ASD or ADHD symptom severity, was the most consistent predictor of problematic sleep behaviors (i.e., nightmares overtiredness, sleeping less than other children, trouble sleeping, and Total Problematic Sleep Behaviors) in this sample. Further, parent report of problematic sleep behaviors was significantly associated with functional domains after controlling for ASD, ADHD, and internalizing symptoms.

CONCLUSIONS

Results suggest that internalizing symptoms are associated with problematic sleep behaviors in children with comorbid ASD/ADHD and may have implications for the "real-life" functioning among children with comorbid ASD/ADHD.

The diagnosis of autism and autism spectrum disorder in low- and middle-income countries: Experience from Jamaica

The administration requirements of the Autism Diagnostic Observation Schedule and the Autism Diagnostic Interview-Revised, widely used in high-income countries, make them less feasible for diagnosis of autism spectrum disorder in low- and middle-income countries. The flexible administration requirements of the Childhood Autism Rating Scale have resulted in its use in both high-income countries and low- and middle-income countries. This study examines the agreement between assessments using the Childhood Autism Rating Scale with those using the Autism Diagnostic Observation Schedule or Autism Diagnostic Observation Schedule, Second Edition and Autism Diagnostic Interview-Revised in Jamaica. Children aged 2-8 years (n = 149) diagnosed with autism by an experienced clinician using the Childhood Autism Rating Scale were re-evaluated using the Autism Diagnostic Observation Schedule and Autism Diagnostic Interview-Revised. The proportion diagnosed with autism spectrum disorder using the Autism Diagnostic Observation Schedule, Autism Diagnostic Observation Schedule, Second Edition, and Autism Diagnostic Interview-Revised was determined and mean domain scores compared using analysis of variance (ANOVA). The mean age was 64.4 (standard deviation = 21.6) months; the male:female ratio was 6:1. The diagnostic agreement of the Childhood Autism Rating Scale with the Autism Diagnostic Observation Schedule and Autism Diagnostic Observation Schedule, Second Edition was 100.0% and 98.0%, respectively. Agreement with the Autism Diagnostic Interview-Revised was 94.6%. Domain scores were highest for children with more severe symptoms (p < 0.01). Despite a high level of agreement of the Childhood Autism Rating Scale with the Autism Diagnostic Observation Schedule, Autism Diagnostic Observation Schedule, Second Edition, and Autism Diagnostic Interview-Revised, the Childhood Autism Rating Scale should be evaluated further with a broader range of autism spectrum disorder symptomatology, and by clinicians with varying experience before recommendation for use in low- and middle-income countries.

ADHD severity as it relates to comorbid psychiatric symptomatology in children with Autism Spectrum Disorders (ASD)

Comorbid diagnoses identified in pediatric samples have been correlated with a range of outcomes, including greater levels of emotional, behavioral, and educational impairment and the need for more intensive treatment. Given that previous research has documented high levels of comorbid Attention-Deficit/Hyperactivity Disorder (ADHD) in children with Autism Spectrum Disorders (ASD), this study closely examines the relationship between parent-reported ADHD symptoms (i.e., Conners' Parent Rating Scale, Revised [CPRS-R]) and the prevalence of additional comorbid psychiatric diagnoses in a pediatric ASD sample (n=99). Regression analyses revealed that greater severity of ADHD symptomatology was significantly related to a greater number of comorbid psychiatric diagnoses, as identified using the Diagnostic Interview for Children and adolescents, 4th Edition (DICA-IV). Additionally, more severe ADHD symptoms were also associated with higher levels of symptom severity on Child Behavior Checklist (CBCL) syndrome subscales. Interestingly, increasing severity of ASD symptomatology, as measured by the Autism Diagnostic Interview, Revised (ADI-R), was not associated with a higher prevalence of comorbid psychiatric diagnoses or CBCL syndrome severity. Our study concluded that higher levels of ADHD severity-not ASD severity-were associated with a higher prevalence of comorbid psychiatric symptomatology in school-age children with ASD. These findings may encourage clinicians to thoroughly assess ADHD symptomatology in ASD children to better inform treatment planning.

Concentrations of Polychlorinated Biphenyls and Organochlorine Pesticides in Umbilical Cord Blood Serum of Newborns in Kingston, Jamaica

To date much of the biomonitoring related to exposure to polychlorinated biphenyls (PCBs) and organochlorine (OC) pesticides is from middle to high income countries, including the U.S., Canada and Europe, but such data are lacking for the majority of low to middle income countries. Using data from 64 pregnant mothers who were enrolled in 2011, we aimed to assess the concentrations of the aforementioned toxins in umbilical cord blood serum of 67 Jamaican newborns. For 97 of the 100 PCB congeners and 16 of the 17 OC pesticides, all (100%) concentrations were below their respective limits of detection (LOD). Mean (standard deviation (SD)) lipid-adjusted concentrations in cord blood serum for congeners PCB-153, PCB-180, PCB-206 and total PCB were 14.25 (3.21), 7.16 (1.71), 7.30 (1.74) and 28.15 (6.03) ng/g-lipid, respectively. The means (SD) for the 4,4'-dichlorodiphenyldichloroethylene (DDE)-hexane fraction and total-DDE were 61.61 (70.78) and 61.60 (70.76) ng/g-lipid, respectively. Compared to the U.S. and Canada, the concentrations of these toxins were lower in cord-blood serum of Jamaican newborns. We discuss that these differences could be partly due to differences in dietary patterns in these countries. Despite limitations in our dataset, our results provide information on the investigated toxins in cord blood serum that could serve as a reference for Jamaican newborns.

Synergic effect of GSTP1 and blood manganese concentrations in Autism Spectrum Disorder

We used data from 100 age- and sex-matched case-control pairs (age 2-8 years) from Jamaica to investigate whether there is an interaction between glutathione-S-transferase (GST) genes and blood manganese concentrations (BMC) in relation to Autism Spectrum Disorder (ASD). Our findings, indicate that among children who had the Ile/Ile genotype for GST pi 1 (GSTP1), those with BMC ≥ 12µg/L had about 4 times higher odds of ASD than those with BMC < 12µg/L, (P=0.03) under a co-dominant genetic model. After adjusting for potential confounders, among the subgroup of children with genotype Ile/Ile, those with BMC ≥ 12µg/L had about six times higher odds of ASD than those with BMC < 12µg/L, (P=0.04). The results were similar when a recessive genetic model was used. These findings suggest a possible synergic effect of BMC and GSTP1 in ASD. Since our analysis included a variety of genetic models and was not adjusted for multiple testing, replication in other populations is warranted.

Interaction between GSTT1 and GSTP1 allele variants as a risk modulating-factor for autism spectrum disorders

We investigated the role of glutathione S-transferase (GST) genes in Autism Spectrum Disorder (ASD). We used data from 111 pairs of age- and sex-matched ASD cases and typically developing (TD) controls between 2-8 years of age from Jamaica to investigate the role of GST pi 1 (GSTP1), GST theta 1 (GSTT1), and GST mu 1 (GSTM1) polymorphisms in susceptibility to ASD. In univariable conditional logistic regression models we did not observe significant associations between ASD status and GSTT1, GSTM1, or GSTP1 genotype (all P > 0.15). However, in multivariable conditional logistic regression models, we identified a significant interaction between GSTP1 and GSTT1 in relation to ASD. Specifically, in children heterozygous for the GSTP1 Ile105Val polymorphism, the odds of ASD was significantly higher in those with the null GSTT1 genotype than those with the other genotypes [Matched Odds Ratio (MOR) = 2.97, 95% CI (1.09, 8.01), P = 0.03]. Replication in other populations is warranted.

Factors associated with blood lead concentrations of children in Jamaica

Lead is a heavy metal known to be detrimental to neurologic, physiologic, and behavioral health of children. Previous studies from Jamaica reported that mean lead levels in soil are four times that of lead levels in some other parts of the world. Other studies detected lead levels in fruits and root vegetables, which were grown in areas with lead contaminated soil. In this study, we investigate environmental factors associated with blood lead concentrations in Jamaican children. The participants in this study comprised 125 typically developing (TD) children (ages 2-8 years) who served as controls in an age- and sex-matched case-control study that enrolled children from 2009-2012 in Jamaica. We administered a questionnaire to assess demographic and socioeconomic information as well as potential exposures to lead through food. Using General Linear Models (GLMs), we identified factors associated with blood lead concentrations in Jamaican children. The geometric mean blood lead concentration (GMBLC) in the sample of children in this study was 2.80 μg dL(-1). In univariable GLM analyses, GMBLC was higher for children whose parents did not have education beyond high school compared to those whose parents had attained this level (3.00 μg dL(-1) vs. 2.31 μg dL(-1); P = 0.05), children living near a high traffic road compared to those who did not (3.43 μg dL(-1) vs. 2.52 μg dL(-1); P < 0.01), and children who reported eating ackee compared to those who did not eat this fruit (2.89 μg dL(-1) vs. 1.65 μg dL(-1); P < 0.05). In multivariable analysis, living near a high traffic road was identified as an independent risk factor for higher adjusted GMBLC (3.05 μg dL(-1) vs. 2.19 μg dL(-1); P = 0.01). While our findings indicate that GMBLC in Jamaican children has dropped by at least 62% during the past two decades, children living in Jamaica still have GMBLC that is twice that of children in more developed countries. In addition, we have identified significant risk factors for higher blood lead concentrations in Jamaican children. We believe increasing awareness among parents regarding these risk factors could potentially lead to a lower level of lead exposure in Jamaican children.

Blood lead concentrations in Jamaican children with and without autism spectrum disorder

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder manifesting by early childhood. Lead is a toxic metal shown to cause neurodevelopmental disorders in children. Several studies have investigated the possible association between exposure to lead and ASD, but their findings are conflicting. Using data from 100 ASD cases (2–8 years of age) and their age- and sex-matched typically developing controls, we investigated the association between blood lead concentrations (BLC) and ASD in Jamaican children. We administered a questionnaire to assess demographic and socioeconomic information as well as exposure to potential lead sources. We used General Linear Models (GLM) to assess the association of BLC with ASD status as well as with sources of exposure to lead. In univariable GLM, we found a significant difference between geometric mean blood lead concentrations of ASD cases and controls (2.25 μg/dL cases vs. 2.73 μg/dL controls, p < 0.05). However, after controlling for potential confounders, there were no significant differences between adjusted geometric mean blood lead concentrations of ASD cases and controls (2.55 μg/dL vs. 2.72 μg/dL, p = 0.64). Our results do not support an association between BLC and ASD in Jamaican children. We have identified significant confounders when assessing an association between ASD and BLC.

Role of fruits, grains, and seafood consumption in blood cadmium concentrations of Jamaican children with and without Autism Spectrum Disorder

Human exposure to cadmium has adverse effects on the nervous system. Utilizing data from 110 age- and sex-matched case-control pairs (220 children) ages 2-8 years in Kingston, Jamaica, we compared the 75th percentile of blood cadmium concentrations in children with and without Autism Spectrum Disorder (ASD). In both univariable and multivariable Quantile Regression Models that controlled for potential confounding factors, we did not find any significant differences between ASD cases and typically developing (TD) controls with respect to the 75th percentile of blood cadmium concentrations, (P > 0.22). However, we found a significantly higher 75th percentile of blood cadmium concentrations in TD Jamaican children who consumed shellfish (lobsters, crabs) (P <0.05), fried plantain (P <0.01), and boiled dumpling (P <0.01). We also observed that children living in Jamaica have an arithmetic mean blood cadmium concentration of 0.16μg/L which is similar to that of the children in developed countries and much lower than that of children in developing countries. Although our results do not support an association between blood cadmium concentrations and ASD, to our knowledge, this study is the first to report levels of blood cadmium in TD children as well as those with ASD in Jamaica.

Blood manganese concentrations in Jamaican children with and without autism spectrum disorders

BACKGROUND

Manganese is an essential element for human health and development. Previous studies have shown neurotoxic effects in children exposed to higher levels of manganese. Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder that impairs social interaction and communication. Several studies have hypothesized that ASD is caused through environmental exposures during crucial stages in brain development. We investigated the possible association between blood manganese concentrations (BMC) and ASD. We also identified factors associated with BMC in typically developing (TD) Jamaican children.

METHODS

We used data from 109 ASD cases with their 1:1 age- and sex-matched TD controls to compare mean BMC in Jamaican children (2-8 years of age) with and without ASD. We administered a pre-tested questionnaire to assess demographic and socioeconomic information, medical history, and potential exposure to manganese. Finally, we collected 2 mL of whole blood from each child for analysis of manganese levels. Using General Linear Models (GLM), we assessed the association between BMC and ASD status. Furthermore, we used two independent sample t-tests to identify factors associated with BMC in TD children.

RESULTS

In univariable GLM analysis, we found no significant association between BMC and ASD, (10.9 μg/L for cases vs. 10.5 μg/L for controls; P = 0.29). In a multivariable GLM adjusting for paternal age, parental education, place of child's birth (Kingston parish), consumption of root vegetables, cabbage, saltwater fish, and cakes/buns, there was still no significant association between BMC and ASD status, (11.5 μg/L for cases vs. 11.9 μg/L for controls; P = 0.48). Our findings also indicated TD children who ate fresh water fish had a higher BMC than children who did not (11.0 μg/L vs. 9.9 μg/L; P = 0.03) as younger TD children (i.e., 2 ≤ age ≤4), (12.0 μg/L vs. 10.2 μg/L; P = 0.01).

CONCLUSIONS

While these results cannot be used to assess early exposure at potentially more susceptible time period, our findings suggest that there is no significant association between manganese exposures and ASD case status in Jamaica. Our findings also indicate that BMC in Jamaican children resemble those of children in the developed world and are much lower than those in the developing countries.

Role of metabolic genes in blood arsenic concentrations of Jamaican children with and without autism spectrum disorder

Arsenic is a toxic metalloid with known adverse effects on human health. Glutathione-S-transferase (GST) genes, including GSTT1, GSTP1, and GSTM1, play a major role in detoxification and metabolism of xenobiotics. We investigated the association between GST genotypes and whole blood arsenic concentrations (BASC) in Jamaican children with and without autism spectrum disorder (ASD). We used data from 100 ASD cases and their 1:1 age- and sex-matched typically developing (TD) controls (age 2-8 years) from Jamaica. Using log-transformed BASC as the dependent variable in a General Linear Model, we observed a significant interaction between GSTP1 and ASD case status while controlling for several confounding variables. However, for GSTT1 and GSTM1 we did not observe any significant associations with BASC. Our findings indicate that TD children who had the Ile/Ile or Ile/Val genotype for GSTP1 had a significantly higher geometric mean BASC than those with genotype Val/Val (3.67 µg/L vs. 2.69 µg/L, p < 0.01). Although, among the ASD cases, this difference was not statistically significant, the direction of the observed difference was consistent with that of the TD control children. These findings suggest a possible role of GSTP1 in the detoxification of arsenic.

Interaction of finger representations in the cortex of individuals with autism: a functional window into cortical inhibition

An established neural biomarker of autism spectrum disorder (ASD) has the potential to provide novel biological and pharmacological targets for treatment. Lower level of inhibition in brain circuits is a leading biomarker candidate. A physiological investigation of the functional levels of inhibition in the cortex of individuals with autism can provide a strong test of the hypothesis. The amplitude of cortical response to the stimulation of adjacent fingers is controlled by the level of cortical inhibition and provides just such a test. Using magnetoencephalography, we recorded the response of the somatosensory cortex to the passive tactile stimulation of the thumb (D1), and index finger (D2), and to the simultaneous stimulation of both fingers combined (D1,D2) of the dominant (right) hand of young subjects with and without autism. For each participant, we measured the response to the stimulation of both fingers combined (D1,D2) relative to the post hoc sum of the responses to the stimulation of each finger alone (D1+D2) in multiple different ways and linearly regressed the ASD and neurotypical (NT) groups' responses. The resulting slopes were then compared: Smaller slope values imply attenuated response to paired finger stimulation, and enhanced levels of inhibition. The short-latency M40 and mid-latency M80 response slopes of the group with autism obtained in different ways were either significantly smaller, or statistically indistinguishable from NT. The result does not support reduced inhibition in the somatosensory cortex of individuals with autism, contrary to the seminal hypothesis of reduced inhibition. Implications are discussed including refinements of current theory.

Effects of extended release methylphenidate treatment on ratings of attention-deficit/hyperactivity disorder (ADHD) and associated behavior in children with autism spectrum disorders and ADHD symptoms

OBJECTIVE

The purpose of this study was to examine the behavioral effects of four doses of psychostimulant medication, combining extended-release methylphenidate (MPH) in the morning with immediate-release MPH in the afternoon.

METHOD

The sample comprised 24 children (19 boys; 5 girls) who met American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV-TR) criteria for an autism spectrum disorder (ASD) on the Autism Diagnostic Interview-Revised (ADI-R) and the Autism Diagnostic Observation Schedule (ADOS), and had significant symptoms of attention-deficit/hyperactivity disorder (ADHD). This sample consisted of elementary school-age, community-based children (mean chronological age=8.8 years, SD=1.7; mean intelligence quotient [IQ]=85; SD=16.8). Effects of four dose levels of MPH on parent and teacher behavioral ratings were investigated using a within-subject, crossover, placebo-controlled design.

RESULTS

MPH treatment was associated with significant declines in hyperactive and impulsive behavior at both home and school. Parents noted significant declines in inattentive and oppositional behavior, and improvements in social skills. No exacerbation of stereotypies was noted, and side effects were similar to those seen in typically developing children with ADHD. Dose response was primarily linear in the dose range studied.

CONCLUSIONS

The results of this study suggest that MPH formulations are efficacious and well-tolerated for children with ASD and significant ADHD symptoms.

Functional assays of local connectivity in the somatosensory cortex of individuals with autism

Emerging evidence for differences between individuals with autism spectrum disorder (ASD) and neurotypical (NT) individuals in somatic processing and brain response to touch suggests somatosensory cortex as a promising substrate for elucidating differences in functional brain connectivity between individuals with and without autism. Signals from adjacent digits project to neighboring locations or representations in somatosensory cortex. When a digit is stimulated, i.e. touched, its representation in cortex is directly activated; local intracortical connections indirectly activate nonprimary cortical representations corresponding to adjacent digits. The response of the nonprimary cortical representations is thus a proxy for connection strength. Local overconnectivity in autism implies that the nonprimary/primary response ratios of the ASD group will be higher than those of the NT group. D1 and D2 of the dominant hand of the participant were individually stimulated while we recorded neural responses using magnetoencephalography. The cortical representations of D1 and D2 (somatosensory-evoked fields) were computed from the ensemble-averaged data using (a) dipole model fits and (b) singular value decomposition. Individual adjacent/primary response ratios were measured, and group response ratio data were fitted with straight lines. Local overconnectivity in autism implies steeper ASD vs. NT group slopes. Our findings did not support local overconnectivity. Slopes were found to be significantly shallower for the ASD group than the NT group. Our findings support the idea of local underconnectivity in the somatosensory cortex of the brains of individuals with ASD.

Seafood consumption and blood mercury concentrations in Jamaican children with and without autism spectrum disorders

Mercury is a toxic metal shown to have harmful effects on human health. Several studies have reported high blood mercury concentrations as a risk factor for autism spectrum disorders (ASDs), while other studies have reported no such association. The goal of this study was to investigate the association between blood mercury concentrations in children and ASDs. Moreover, we investigated the role of seafood consumption in relation to blood mercury concentrations in Jamaican children. Based on data for 65 sex- and age-matched pairs (2-8 years), we used a General Linear Model to test whether there is an association between blood mercury concentrations and ASDs. After controlling for the child's frequency of seafood consumption, maternal age, and parental education, we did not find a significant difference (P = 0.61) between blood mercury concentrations and ASDs. However, in both cases and control groups, children who ate certain types of seafood (i.e., salt water fish, sardine, or mackerel fish) had significantly higher (all P < 0.05) geometric means blood mercury concentration which were about 3.5 times that of children living in the US or Canada. Our findings also indicate that Jamaican children with parents who both had education up to high school are at a higher risk of exposure to mercury compared to children with at least one parent who had education beyond high school. Based on our findings, we recommend additional education to Jamaican parents regarding potential hazards of elevated blood mercury concentrations, and its association with seafood consumption and type of seafood.

Maternal and paternal age are jointly associated with childhood autism in Jamaica

Several studies have reported maternal and paternal age as risk factors for having a child with Autism Spectrum Disorder (ASD), yet the results remain inconsistent. We used data for 68 age- and sex-matched case-control pairs collected from Jamaica. Using Multivariate General Linear Models (MGLM) and controlling for parity, gestational age, and parental education, we found a significant (p < 0.0001) joint effect of parental ages on having children with ASD indicating an adjusted mean paternal age difference between cases and controls of [5.9 years; 95% CI (2.6, 9.1)] and a difference for maternal age of [6.5 years; 95% CI (4.0, 8.9)]. To avoid multicollinearity in logistic regression, we recommend joint modeling of parental ages as a vector of outcome variables using MGLM.

The role of drinking water sources, consumption of vegetables and seafood in relation to blood arsenic concentrations of Jamaican children with and without Autism Spectrum Disorders

Arsenic is a toxic metal with harmful effects on human health, particularly on cognitive function. Autism Spectrum Disorders (ASDs) are lifelong neurodevelopmental and behavioral disorders manifesting in infancy or early childhood. We used data from 130 children between 2 and 8 years (65 pairs of ASD cases with age- and sex-matched control), to compare the mean total blood arsenic concentrations in children with and without ASDs in Kingston, Jamaica. Based on univariable analysis, we observed a significant difference between ASD cases and controls (4.03 μg/L for cases vs. 4.48 μg/L for controls, P<0.01). In the final multivariable General Linear Model (GLM), after controlling for car ownership, maternal age, parental education levels, source of drinking water, consumption of "yam, sweet potato, or dasheen", "carrot or pumpkin", "callaloo, broccoli, or pak choi", cabbage, avocado, and the frequency of seafood consumption per week, we did not find a significant association between blood arsenic concentrations and ASD status (4.36 μg/L for cases vs. 4.65 μg/L for controls, P=0.23). Likewise, in a separate final multivariable GLM, we found that source of drinking water, eating avocado, and eating "callaloo, broccoli, or pak choi" was significantly associated with higher blood arsenic concentrations (all three P<0.05). Based on our findings, we recommend assessment of arsenic levels in water, fruits, and vegetables, as well as increased awareness among the Jamaican population regarding potential risks for various exposures to arsenic.

High concordance of parent and teacher attention-deficit/hyperactivity disorder ratings in medicated and unmedicated children with autism spectrum disorders

OBJECTIVE

Parent and teacher ratings of core attention-deficit/hyperactivity disorder (ADHD) symptoms, as well as behavioral and emotional problems commonly comorbid with ADHD, were compared in children with autism spectrum disorders (ASD).

METHOD

Participants were 86 children (66 boys; mean: age=9.3 years, intelligence quotient [IQ]=84) who met American Psychiatric Association Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV) criteria for an ASD on the Autism Diagnostic Interview-Revised (ADI-R) and the Autism Diagnostic Observation Schedule (ADOS). Parent and teacher behavioral ratings were compared on the Conners' Parent and Teacher Rating Scales (CPRS-R; CTRS-R). The degree to which age, ASD subtype, severity of autistic symptomatology, and medication status mediated this relationship was also examined.

RESULTS

Significant positive correlations between parent and teacher ratings suggest that a child's core ADHD symptoms-as well as closely related externalizing symptoms-are perceived similarly by parents and teachers. With the exception of oppositional behavior, there was no significant effect of age, gender, ASD subtype, or autism severity on the relationship between parent and teacher ratings. In general, parents rated children as having more severe symptomatology than did teachers. Patterns of parent and teacher ratings were highly correlated, both for children who were receiving medication, and for children who were not.

CONCLUSIONS

Parents and teachers perceived core symptoms of ADHD and closely-related externalizing problems in a similar manner, but there is less agreement on ratings of internalizing problems (e.g., anxiety). The clinical implication of these findings is that both parents and teachers provide important behavioral information about children with ASD. However, when a clinician is unable to access teacher ratings (e.g., during school vacations), parent ratings can provide a reasonable estimate of the child's functioning in these domains in school. As such, parent ratings can be reliably used to make initial diagnostic and treatment decisions (e.g., medication treatment) regarding ADHD symptoms in children with ASDs.

Detecting social and non-social changes in natural scenes: performance of children with and without autism spectrum disorders and typical adults

We probed differences in the ability to detect and interpret social cues in adults and in children and young adolescents with and without autism spectrum disorders (ASD) by investigating the effect of various social and non-social contexts on the visual exploration of pictures of natural scenes. Children and adolescents relied more on social referencing cues in the scene as compared to adults, and in the presence of such cues, were less able to use other kinds of cues. Typically developing children and adolescents were no better than those with ASD at detecting changes within the various social contexts. Results suggest children and adolescents with ASD use relevant social cues while searching a scene just as typical children do.

Judgments of auditory-visual affective congruence in adolescents with and without autism: a pilot study of a new task using fMRI

One of the most widely reported developmental deficits associated with autism is difficulty perceiving and expressing emotion appropriately. Brain activation associated with performance on a new task, the Emotional Congruence Task, requires judging affective congruence of facial expression and voice, compared with their sex congruence. Participants in this pilot study were adolescents with normal IQ (n = 5) and autism or without (n = 4) autism. In the emotional congruence condition, as compared to the sex congruence of voice and face, controls had significantly more activation than the Autism group in the orbitofrontal cortex, the superior temporal, parahippocampal, and posterior cingulate gyri and occipital regions. Unlike controls, the Autism group did not have significantly greater prefrontal activation during the emotional congruence condition, but did during the sex congruence condition. Results indicate the Emotional Congruence Task can be used successfully to assess brain activation and behavior associated with integration of auditory and visual information for emotion. While the numbers in the groups are small, the results suggest that brain activity while performing the Emotional Congruence Task differed between adolescents with and without autism in fronto-limbic areas and in the superior temporal region. These findings must be confirmed using larger samples of participants.

Fronto-limbic functioning in children and adolescents with and without autism

We used neuropsychological tasks to investigate integrity of brain circuits linking orbitofrontal cortex and amygdala (orbitofrontal-amygdala), and dorsolateral prefrontal cortex and hippocampus (dorsolateral prefrontal-hippocampus), in 138 individuals aged 7-18 years, with and without autism. We predicted that performance on orbitofrontal-amygdala tasks would be poorer in the Autism group compared to the Non-Autism group regardless of intellectual level (verbal mental age, VMA) and that performance on dorsolateral prefrontal-hippocampus tasks would be associated primarily with intellectual level. Predicted differences between Autism and Non-Autism groups on orbitofrontal-amygdala tasks were present but greater in individuals with higher VMA. On dorsolateral prefrontal-hippocampus tasks, poorer performance by the Autism compared to the Non-Autism group was found at all VMA levels. Group differences suggest both brain circuits are impaired in autism, but performance on all tasks is also associated with intellectual level.

A Comparison of Behavioral and Emotional Functioning in Children and Adolescents with Autistic Disorder and PDD-NOS

Behavioral symptomatology was compared in 26 children and adolescents with Autistic Disorder ("autism") and 25 children and adolescents with Pervasive Developmental Disorder, Not Otherwise Specified ("PDD-NOS"). Relative to individuals with PDD-NOS, those with autism had more symptoms of depression, social withdrawal, atypical behavior, and immature social skills--and fewer family problems. These differences remained even when group differences in intellectual ability were statistically controlled. No group differences emerged in somatization, anxiety, or hyperactivity. Findings suggest that although both groups demonstrate considerable evidence of behavioral and emotional problems, those with autism are at particularly high risk for comorbid behavioral and emotional disabilities.

Improving the reliability of autism diagnoses: examining the utility of adaptive behavior

The classification agreement of the Autism Diagnostic Interview-Revised (ADI-R) and the Autism Diagnostic Observation Schedule (ADOS) was examined in 129 children and adolescents (aged 7-18 years) who were evaluated for autism. Participants received a diagnosis of autism or non-autism based on the ADI-R. Linear discriminant analysis revealed adequate concordance between the ADI-R and ADOS, with 75% of the participants being correctly classified using the ADOS. Classification accuracy significantly improved to 84% when a measure of adaptive functioning (i.e., the Vineland Adaptive Behavior Scales) was included in the analysis. The findings suggest that when clinicians obtain discrepant information on the ADI-R and ADOS, assessment of an individual's adaptive functioning may reduce diagnostic errors.

Index finger movement imitation by human neonates: motivation, learning, and left-hand preference

Imitation of a fine motor movement, index finger protrusion, was examined in 39 neonates using an ethologically based objective coding system. Results confirmed that imitation of finger movements exists, and infants demonstrated "learning" as imitation developed through an incomplete imitation stage. Neonatal imitation was more frequently left-handed, an early sign of laterality in motivation to be investigated further. The existence of index finger imitation in human neonates indicates that volitional control of individuated finger movements develops much earlier than previously thought. The differential increase of index finger protrusion movements during the imitation periods suggests that this behavior is not an automatic response triggered by general arousal but instead is a true indicator of purposeful neonatal imitation.

The orbitofrontal-amygdala circuit and self-regulation of social-emotional behavior in autism

Individuals with an autistic spectrum disorder are impaired not only in understanding others' mental states, but also in self-regulation of social-emotional behavior. Therefore, a model of the brain in autism must encompass not only those brain systems that subserve social-cognitive and emotional functioning, but also those that subserve the self-regulation of behavior in response to a changing social environment. We present evidence to support the hypothesis that developmental dysfunction of the orbitofrontal-amygdala circuit of the brain is a critical factor in the development of autism and that some of the characteristic deficits of persons with autism in socio-emotional cognition and behavioral self-regulation are related to early dysfunction of different components of this circuit. A secondary hypothesis posits that the degree of intellectual impairment present in individuals with autism is directly related to the integrity of the dorsolateral prefrontal-hippocampal circuit of the brain. Together, these hypotheses have the potential to help explain the neurodevelopmental basis of some of the primary manifestations of autism as well as the heterogeneity of outcomes.

Role of Orientation in Perception of Emotions

Our study examined whether perception of novel emotions, as with perception of novel objects, elicits a cardiac orientation reaction. Using a habituation-dishabituation paradigm, data from 11 adult subjects showed that orientation to both novel emotions and novel objects elicited a heart-rate deceleration. Results suggest that the orientation reaction may be an integral part of perception of emotion. Perception of emotions, therefore, is a complex, multistep process that includes an early orientation reaction.