292 research outputs found
Autism with intellectual disability is associated with increased levels of maternal cytokines and chemokines during gestation.
Immune abnormalities have been described in some individuals with autism spectrum disorders (ASDs) as well as their family members. However, few studies have directly investigated the role of prenatal cytokine and chemokine profiles on neurodevelopmental outcomes in humans. In the current study, we characterized mid-gestational serum profiles of 22 cytokines and chemokines in mothers of children with ASD (N=415), developmental delay (DD) without ASD (N=188), and general population (GP) controls (N=428) using a bead-based multiplex technology. The ASD group was further divided into those with intellectual disabilities (developmental/cognitive and adaptive composite score<70) (ASD+ID, N=184) and those without (composite score⩾70) (ASD-noID, N=201). Levels of cytokines and chemokines were compared between groups using multivariate logistic regression analyses, adjusting for maternal age, ethnicity, birth country and weight, as well as infant gender, birth year and birth month. Mothers of children with ASD+ID had significantly elevated mid-gestational levels of numerous cytokines and chemokines, such as granulocyte macrophage colony-stimulating factor, interferon-γ, interleukin-1α (IL-1α) and IL-6, compared with mothers of children with either ASD-noID, those with DD, or GP controls. Conversely, mothers of children with either ASD-noID or with DD had significantly lower levels of the chemokines IL-8 and monocyte chemotactic protein-1 compared with mothers of GP controls. This observed immunologic distinction between mothers of children with ASD+ID from mothers of children with ASD-noID or DD suggests that the intellectual disability associated with ASD might be etiologically distinct from DD without ASD. These findings contribute to the ongoing efforts toward identification of early biological markers specific to subphenotypes of ASD
Scaling of the surface vasculature on the human placenta
The networks of veins and arteries on the chorionic plate of the human placenta are analyzed in terms of Voronoi cells derived from these networks. Two groups of placentas from the United States are studied: a population cohort with no prescreening, and a cohort from newborns with an elevated risk of developing autistic spectrum disorder. Scaled distributions of the Voronoi cell areas in the two cohorts collapse onto a single distribution, indicating common mechanisms for the formation of the complete vasculatures, but which have different levels of activity in the two cohorts
Parental and Grandparental Ages in the Autistic Spectrum Disorders: A Birth Cohort Study
Background: A number of studies have assessed ages of parents of children with autistic spectrum disorders (ASD), and reported both maternal and paternal age effects. Here we assess relationships with grandparental ages. Methods and Findings: We compared the parental and grandparental ages of children in the population-based Avon Longitudinal Study of Parents and Children (ALSPAC), according to their scores in regard to 4 autistic trait measures and whether they had been given a diagnosis of ASD. Mean maternal and paternal ages of ASD cases were raised, but this appears to be secondary to a maternal grandmother age effect (P = 0.006): OR = 1.66[95%CI 1.16, 2.37] for each 10-year increase in the grandmother’s age at the birth of the mother. Trait measures also revealed an association between the maternal grandmother’s age and the major autistic trait–the Coherence Scale (regression coefficient b = 0.142, [95%CI = 0.057, 0.228]P = 0.001). After allowing for confounders the effect size increased to b = 0.217[95%CI 0.125, 0.308](P,0.001) for each 10 year increase in age. Conclusions: Although the relationship between maternal grandmother’s age and ASD and a major autistic trait was unexpected, there is some biological plausibility, for the maternal side at least, given that the timing of female meiosis I permits direct effects on the grandchild’s genome during the grandmother’s pregnancy. An alternative explanation is the meiotic mismatch methylation (3 M) hypothesis, presented here for the first time. Nevertheless the findings should b
Does the risk of cerebral palsy increase or decrease with increasing gestational age?
BACKGROUND: It is generally accepted that the risk of cerebral palsy decreases with increasing gestational age of live born infants. However, recent studies have shown that cerebral palsy often has prenatal antecedents including congenital malformations, vascular insults and maternal infection. Cerebral palsy is therefore better viewed as occurring among fetuses, rather than among infants. We explored the epidemiologic implications of this change in perspective. METHODS: We used recently published data from Shiga Prefecture, Japan and from North-East England to examine the pattern of gestational age-specific rates of cerebral palsy under these alternative perspectives. We first calculated gestational age-specific rates of cerebral palsy as per convention, by dividing the number of cases of cerebral palsy identified among live births within any gestational age category by the number of live births in that gestational age category. Under the alternative formulation, we calculated gestational age-specific rates of cerebral palsy by dividing the number of cases of cerebral palsy identified among live births within any gestational age category by the number of fetuses who were at risk of being born at that gestation and being afflicted with cerebral palsy. RESULTS: Under the conventional formulation, cerebral palsy rates decreased with increasing gestational age from 63.9 per 1,000 live births at <28 weeks gestation to 0.9 per 1,000 live births at 37 or more weeks gestation. When fetuses were viewed as potential candidates for cerebral palsy, cerebral palsy rates increased with increasing gestational age from 0.08 per 1,000 fetuses at risk at <28 weeks gestation to 0.9 per 1,000 fetuses at risk at 37 or more weeks gestation. CONCLUSIONS: The fetuses-at-risk approach is the appropriate epidemiologic formulation for calculating the gestational age-specific rate of cerebral palsy from a causal perspective. It shows that the risk of cerebral palsy increases as gestational duration increases. This compelling view of cerebral palsy risk may help refocus research aimed at understanding and preventing cerebral palsy
Genes encoding critical transcriptional activators for murine neural tube development and human spina bifida: a case-control study
<p>Abstract</p> <p>Background</p> <p>Spina bifida is a malformation of the neural tube and is the most common of neural tube defects (NTDs). The etiology of spina bifida is largely unknown, although it is thought to be multi-factorial, involving multiple interacting genes and environmental factors. Mutations in transcriptional co-activator genes-<it>Cited2</it>, <it>p300</it>, <it>Cbp</it>, <it>Tfap2α</it>, <it>Carm1 </it>and <it>Cart1 </it>result in NTDs in murine models, thus prompt us to investigate whether homologues of these genes are associated with NTDs in humans.</p> <p>Methods</p> <p>Data and biological samples from 297 spina bifida cases and 300 controls were derived from a population-based case-control study conducted in California. 37 SNPs within <it>CITED2</it>, <it>EP300</it>, <it>CREBBP</it>, <it>TFAP2A</it>, <it>CARM1 </it>and <it>ALX1 </it>were genotyped using an ABI SNPlex assay. Odds ratios and 95% confidence intervals were calculated for alleles, genotypes and haplotypes to evaluate the risk for spina bifida.</p> <p>Results</p> <p>Several SNPs showed increased or decreased risk, including <it>CITED2 </it>rs1131431 (OR = 5.32, 1.04~27.30), <it>EP300 </it>rs4820428 (OR = 1.30, 1.01~1.67), <it>EP300 </it>rs4820429 (OR = 0.50, 0.26~0.50, in whites, OR = 0.7, 0.49~0.99 in all subjects), <it>EP300 </it>rs17002284 (OR = 0.43, 0.22~0.84), <it>TFAP2A </it>rs3798691 (OR = 1.78, 1.13~2.87 in Hispanics), <it>CREBBP </it>rs129986 (OR = 0.27, 0.11~0.69), <it>CARM1 </it>rs17616105 (OR = 0.41, 0.22~0.72 in whites). In addition, one haplotype block in <it>EP300 </it>and one in <it>TFAP2A </it>appeared to be associated with increased risk.</p> <p>Conclusions</p> <p>Modest associations were observed in <it>CITED2</it>, <it>EP300</it>, <it>CREBBP</it>, <it>TFAP2A </it>and <it>CARM1 </it>but not <it>ALX1</it>. However, these modest associations were not statistically significant after correction for multiple comparisons. Searching for potential functional variants and rare causal mutations is warranted in these genes.</p
Autism and Intellectual Disability Are Differentially Related to Sociodemographic Background at Birth
Background: Research findings investigating the sociodemographics of autism spectrum disorder (ASD) have been inconsistent and rarely considered the presence of intellectual disability (ID). Methods: We used population data on Western Australian singletons born from 1984 to 1999 (n = 398,353) to examine the sociodemographic characteristics of children diagnosed with ASD with or without ID, or ID without ASD compared with non-affected children. Results: The profiles for the four categories examined, mild-moderate ID, severe ID, ASD without ID and ASD with ID varied considerably and we often identified a gradient effect where the risk factors for mild-moderate ID and ASD without ID were at opposite extremes while those for ASD with ID were intermediary. This was demonstrated clearly with increased odds of ASD without ID amongst older mothers aged 35 years and over (odds ratio (OR) = 1.69 [CI: 1.18, 2.43]), first born infants (OR = 2.78; [CI: 1.67, 4.54]), male infants (OR = 6.57 [CI: 4.87, 8.87]) and increasing socioeconomic advantage. In contrast, mild-moderate ID was associated with younger mothers aged less than 20 years (OR = 1.88 [CI: 1.57, 2.25]), paternal age greater than 40 years (OR = 1.59 [CI: 1.36, 1.86]), Australian-born and Aboriginal mothers (OR = 1.60 [CI: 1.41, 1.82]), increasing birth order and increasing social disadvantage (OR = 2.56 [CI: 2.27, 2.97]). Mothers of infants residing in regional or remote areas had consistently lower risk of ASD or ID and may be linked to reduced access to services or underascertainment rather than a protective effect of location. Conclusions: The different risk profiles observed between groups may be related to aetiological differences or ascertainment factors or both. Untangling these pathways is challenging but an urgent public health priority in view of the supposed autism epidemic
Does routine child health surveillance contribute to the early detection of children with pervasive developmental disorders? – An epidemiological study in Kent, U.K.
BACKGROUND: Recently changed guidelines for child health surveillance in the United Kingdom (U.K.) suggest targeted checks only, instead of the previously conducted routine or universal screening at 2 years and 3.5 years. There are concerns that these changes could lead to a delay in the detection of children with autism and other pervasive developmental disorders (PDD). Recent U.K. studies have suggested that the prevalence of PDD is much higher than previously estimated. This study establishes to which extent the routine checks contributed to the early detection and assessment of cases of PDD. Simultaneously we have evaluated the process involved and estimate the prevalence of PDD in our district. METHODS: Retrospective study design utilising community medical files. Headteachers of schools (n = 75) within Maidstone district (Kent) were asked to report all children with an established diagnosis of autism or PDD attending year 4 (born '91 and '92 / n = 2536) in October 2000 based on educational records. RESULTS: 59 schools (78.7%) took part in the study. A total of 33 children were reported. 21 fulfilled the inclusion criteria (12 falsely reported). The prevalences were (per 10,000): PDD 82.8 (male to female ratio 6:1), childhood autism 23.7, Asperger's syndrome 11.8 and autistic spectrum disorder 47.3. Co-existing medical conditions were noted in 14.3%; 52.4% were attending mainstream schools. In 63.2% of cases concerns – mainly in the area of speech and language development (SLD) – had been documented at the 2 year check. At the 3.5 year check concerns were noted in 94.1% – the main area was again SLD (76.5%), although behavioural abnormalities were becoming more frequent (47.1%). A total of 13 children (68.4%) were referred for further assessment as a direct result of the checks. CONCLUSIONS: The prevalences for different types of PDD were similar to figures published recently, but much higher than reported a few years ago. Analysis of our data suggests that routine surveillance is a valuable contributing factor for the early detection of PDD and thereby facilitates early intervention. Thus, if routine surveillance ceases, then an alternative method of early detection should be put in place
Parent-reported health care expenditures associated with autism spectrum disorders in Heilongjiang province, China
<p>Abstract</p> <p>Background</p> <p>The aim of this study was to determine the health expenses incurred by families with children with autism spectrum disorder (ASD) and those expenses' relation to total household income and expenditures.</p> <p>Methods</p> <p>In this cross-sectional study, health care expenditure data were collected through face-to-face interviews. Expenses included annual costs for clinic visits, medication, behavioral therapy, transportation, and accommodations. Health care costs as a percentage of total household income and expenditures were also determined. The participants included 290 families with ASD children who were treated at the Children Development and Behavior Research Center, Harbin Medical University, China.</p> <p>Results</p> <p>Families with ASD children from urban and rural areas had higher per-capita household expenditures by 60.8% and 74.7%, respectively, compared with provincial statistics for 2007. Behavioral therapy accounted for the largest proportion of health expenses (54.3%) for ASD children. In 19.9% of urban and 38.2% of rural families, health care costs exceeded the total annual household income. Most families (89.3% of urban families; 88.1% of rural families) in that province reported higher health care expenditures than the provincial household average.</p> <p>Conclusion</p> <p>For families with ASD children, the economic burden of health care is substantially higher than the provincial average.</p
Underdiagnosis and referral bias of autism in ethnic minorities
This study examined (1) the distribution of ethnic minorities among children referred to autism institutions and (2) referral bias in pediatric assessment of autism in ethnic minorities. It showed that compared to the known community prevalence, ethnic minorities were under-represented among 712 children referred to autism institutions. In addition, pediatricians (n = 81) more often referred to autism when judging clinical vignettes of European majority cases (Dutch) than vignettes including non-European minority cases (Moroccan or Turkish). However, when asked explicitly for ratings of the probability of autism, the effect of ethnic background on autism diagnosis disappeared. We conclude that the use of structured ratings may decrease the likelihood of ethnic bias in diagnostic decisions of autis
CHKA and PCYT1A gene polymorphisms, choline intake and spina bifida risk in a California population
BACKGROUND: Neural tube defects (NTDs) are among the most common of all human congenital defects. Over the last two decades, accumulating evidence has made it clear that periconceptional intake of folic acid can significantly reduce the risk of NTD affected pregnancies. This beneficial effect may be related to the ability of folates to donate methyl groups for critical physiological reactions. Choline is an essential nutrient and it is also a methyl donor critical for the maintenance of cell membrane integrity and methyl metabolism. Perturbations in choline metabolism in vitro have been shown to induce NTDs in mouse embryos. METHODS: This study investigated whether single nucleotide polymorphisms (SNPs) in human choline kinase A (CHKA) gene and CTP:phosphocholine cytidylytransferase (PCYT1A) gene were risk factors for spina bifida. Fluorescence-based allelic discrimination analysis was performed for the two CHKA intronic SNPs hCV1562388 (rs7928739) and hCV1562393, and PCYT1A SNP rs939883 and rs3772109. The study population consisted of 103 infants with spina bifida and 338 non-malformed control infants who were born in selected California counties in the period 1989–1991. RESULTS: The CHKA SNP hCV1562388 genotypes with at least one C allele were associated with a reduced risk of spina bifida (odds ratio = 0.60, 95%CI = 0.38–0.94). The PCYT1A SNP rs939883 genotype AA was associated with a twofold increased risk of spina bifida (odds ratio = 1.89, 95% CI = 0.97–3.67). These gene-only effects were not substantially modified by analytic consideration to maternal periconceptional choline intake. CONCLUSION: Our analyses showed genotype effects of CHKA and PCYT1A genes on spina bifida risk, but did not show evidence of gene-nutrient interactions. The underlying mechanisms are yet to be resolved
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