Intellectual Disability Status Research Articles

3-generation family histories of mental, neurologic, cardiometabolic, birth defect, asthma, allergy, and autoimmune conditions associated with autism: an open-source catalogue of findings.

The relatively few conditions and family members investigated in autism family health history limits etiologic understanding. For more comprehensive understanding and hypothesis-generation we produced an open-source catalogue of autism associations with family histories of mental, neurologic, cardiometabolic, birth defect, asthma, allergy, and autoimmune conditions. All live births in Denmark, 1980-2012, of Denmark-born parents (1,697,231 births), and their 3-generation family members were followed through April 10, 2017 for each of 90 diagnoses (including autism), emigration or death. Adjusted hazard ratios (aHR) were estimated via Cox regression for each diagnosis-family member type combination, adjusting for birth year, sex, birth weight, gestational age, parental ages at birth, and number of family member types of index person; aHRs also calculated for sex-specific co-occurrence of each disorder. We obtained 6,462 individual family history aHRS across autism overall (26,840 autistic persons; 1.6% of births), by sex, and considering intellectual disability (ID); and 350 individual co-occurrence aHRS. Results are catalogued in interactive heat maps and down-loadable data files: https://ncrr-au.shinyapps.io/asd-riskatlas/ and interactive graphic summaries: https://public.tableau.com/views/ASDPlots_16918786403110/e-Figure5. While primarily for reference material or use in other studies (e.g., meta-analyses), results revealed considerable breadth and variation in magnitude of familial health history associations with autism by type of condition, family member type, sex of the family member, side of the family, sex of the index person, and ID status, indicative of diverse genetic, familial, and non-genetic autism etiologic pathways. Careful attention to sources of autism likelihood in family health history, aided by our open data resource, may accelerate understanding of factors underlying neurodiversity.

Evidence for the additivity of rare and common variant burden throughout the spectrum of intellectual disability

Intellectual disability (ID) is a common disorder, yet there is a wide spectrum of impairment from mild to profoundly affected individuals. Mild ID is seen as the low extreme of the general distribution of intelligence, while severe ID is often seen as a monogenic disorder caused by rare, pathogenic, highly penetrant variants. To investigate the genetic factors influencing mild and severe ID, we evaluated rare and common variation in the Northern Finland Intellectual Disability cohort (n = 1096 ID patients), a cohort with a high percentage of mild ID (n = 550) and from a population bottleneck enriched in rare, damaging variation. Despite this enrichment, we found only a small percentage of ID was due to recessive Finnish-enriched variants (0.5%). A larger proportion was linked to dominant variation, with a significant burden of rare, damaging variation in both mild and severe ID. This rare variant burden was enriched in more severe ID (p = 2.4e-4), patients without a relative with ID (p = 4.76e-4), and in those with features associated with monogenic disorders. We also found a significant burden of common variants associated with decreased cognitive function, with no difference between mild and more severe ID. When we included common and rare variants in a joint model, the rare and common variants had additive effects in both mild and severe ID. A multimodel inference approach also found that common and rare variants together best explained ID status (ΔAIC = 16.8, ΔBIC = 10.2). Overall, we report evidence for the additivity of rare and common variant burden throughout the spectrum of intellectual disability.

Adolescents With Autism Spectrum Disorder: Diagnostic Patterns, Co-occurring Conditions, and Transition Planning

PurposeThe objectives of this study were to describe child characteristics associated with later autism spectrum disorder (ASD) identification and the health status and educational transition plans of adolescents with ASD. MethodsLongitudinal population-based surveillance cohort from the Autism Developmental Disabilities Monitoring Network during 2002–2018 in five catchment areas in the United States. Participants included 3,148 children born in 2002 whose records were first reviewed for ASD surveillance in 2010. ResultsOf the 1,846 children identified in the community as an ASD case, 11.6% were first identified after age 8 years. Children who were more likely to have ASD identified at older ages were Hispanic; were born with low birth weight; were verbal; had high intelligence quotient or adaptive scores; or had certain co-occurring neuropsychological conditions by age 8 years. By age 16 years, neuropsychological conditions were common with more than half of the adolescents with ASD having a diagnosis of attention-deficit/hyperactivity disorder or anxiety. Intellectual disability (ID) status was unchanged for the majority (>80%) of children from ages 8–16 years. A transition plan was completed for over 94% of adolescents, but disparities were observed in planning by ID status. DiscussionA high percentage of adolescents with ASD have co-occurring neuropsychological conditions, markedly higher than at age 8. While most adolescents had transition planning, this occurred less often for those with ID. Ensuring access to services for all people with ASD during adolescence and transition to adulthood may help to promote overall health and quality of life.

Prevalence and Disparities in the Detection of Autism Without Intellectual Disability.

Intellectual ability predicts functional outcomes for children with autism spectrum disorder (ASD). It is essential to classify ASD children with and without intellectual disability (ID) to aid etiological research, provide services, and inform evidence-based educational and health planning. Using a cross-sectional study design, data from 2000 to 2016 active ASD surveillance among 8-year-olds residing in the New York-New Jersey Metropolitan Area were analyzed to determine ASD prevalence with and without ID. Multivariable Poisson regression models were used to identify trends for ASD with ID (ASD-I) and without ID (ASD-N). Overall, 4661 8-year-olds were identified with ASD. Those that were ASI-I were 1505 (32.3%) and 2764 (59.3%) were ASD-N. Males were 3794 (81.4%), 946 (20.3%) were non-Hispanic Black (Black), 1230 (26.4%) were Hispanic, and 2114 (45.4%) were non-Hispanic white (white). We observed 2-fold and 5-fold increases in the prevalence of ASD-I and ASD-N, respectively, from 2000-2016. Black children were 30% less likely to be identified with ASD-N compared with white children. Children residing in affluent areas were 80% more likely to be identified with ASD-N compared with children in underserved areas. A greater proportion of children with ASD-I resided in vulnerable areas compared with children with ASD-N. Males had higher prevalence compared with females regardless of ID status; however, male-to-female ratios were slightly lower among ASD-I compared with ASD-N cases. One-in-3 children with ASD had ID. Disparities in the identification of ASD without ID were observed among Black and Hispanic children as well as among children residing in underserved areas.

Accessibility of child protection investigations during pandemic: A qualitative analysis of court proceedings.

Qualitative research using published court records to examine contextual factors that contribute to child protection decisions in cases involving parents with intellectual disabilities is limited, particularly during the COVID-19 pandemic. The present study conducted qualitative content analysis on 10 published Ontario court cases to study child protection decision-making between 2019 and 2021. The findings corroborated previous literature with nine out of 10 cases resulting in loss of child custody. Four major themes emerged from content analysis: (1) Impact of COVID-19 pandemic on cases; (2) Systemic barriers to accessibility; (3) Attitudes and bias toward parents with intellectual disabilities; and (4) Ultimate reliance on intellectual disability status for final custody decision. Conducting content analysis on published court cases is useful in learning about accessibility barriers for parents with intellectual disabilities and may help in understanding the impact of the COVID-19 pandemic on the child protection system.

Child protection involvement of children of mothers with intellectual disability

BackgroundChildren born to parents with intellectual disability (ID) have been shown as disproportionally represented in child protection services however with limited population-based research. ObjectivesTo investigate child protection involvement for children born to mothers with ID in Western Australia using linked administrative data. Participants and settingA cohort of 1106 children born to a mother with ID and a comparison group of 9796 children of mothers without ID were identified in Western Australia. MethodsCox regression analyses stratified by maternal Aboriginal status were conducted to investigate risk of child involvement with child protection services and care placement. Interaction with child age, intellectual disability status, and maternal mental health and substance use was investigated. ResultsChildren born to a mother with ID were both at higher risk of having contact with child protection services (HR: 4.35 (3.70–5.12)) and placement in out-of-home care (HR: 6.21 (4.73–8.17)). For non-Aboriginal children, the risks of child protection involvement and placement for those born to mothers with ID were 7 times and 12 times higher than those of mothers without ID. The risk was lower for Aboriginal children, at 1.8 and 1.9 times, respectively. Infants born to mothers with ID were at higher risk of child protection involvement compared to other age groups. Maternal mental health and substance use moderated the increased risk. ConclusionsIntellectual disability alone is not sufficient justification for removal of children from their parents. The challenge for family services is ensuring that resources are adequate to meet the family's needs.

The role of physical environmental characteristics and intellectual disability in conduct problem trajectories across childhood: A population-based Cohort study

BackgroundThe paucity of research investigating the role of the physical environment in the developmental progression of conduct problems and the potential moderating effects of intellectual disability (ID) is surprising, given the clinical relevance of elucidating environmental determinants of disruptive behaviours. AimsTo use data from a large UK cohort study to assess associations between physical environmental exposures, ID, and conduct problem trajectories. MethodThe sample included 8168 Millennium Cohort Study children (1.9% with ID). Multilevel growth curve modelling was used to examine the role of physical environment characteristics in the developmental trajectories of conduct problems after adjustments for ID status. ResultsExposure to external environmental domains was not associated with differences in children's conduct problems across development. Alternatively, internal aspects of the household environment: spatial density (b = 0.40, p < .001) and damp problems (b = 0.14, p < .001) were both significantly associated with increased trajectories. Various individual and familial covariates were positively associated with conduct problems over time, including: presence of ID (b = 0.96, p < .001), autism spectrum disorder (b = 1.18, p < .001), male sex (b = 0.26, p < .001), poverty (b = 0.19, p < .001), maternal depression (b = 0.65, p < .001), and non-nuclear family structure (b = 0.35, p < .001). Positive ID status appeared to moderate the effects of internal household spatial density, reporting a non-linear negative association with spatial density and conduct problems across development (b = −1.08, p < .01). ConclusionsOur findings highlight the potential harmful consequences of poor internal residential conditions on children's development of disruptive behaviours.

Parent couple conflict and emotional and behavioral problems in youth with autism: Longitudinal investigation of bidirectional effects.

Families of youth with autism spectrum disorder (ASD) are vulnerable to maladaptive psychosocial experiences, including elevated youth emotional and behavioral problems (EBPs) and poor parent couple relationship outcomes. Yet, the extent to which these family psychosocial experiences are intertwined has been given little research attention. The present study longitudinally investigated the bidirectional associations between parent couple conflict (PCC) and youth EBPs in 188 families of children and adolescents with ASD (initially aged 5 to 12 years) across four time points (T1, T2, T3, T4), each spaced 12 months apart. Mother- and father-report of youth EBPs and PCC were entered into a cross-lagged panel model. After adjusting for youth age and intellectual disability status and parent education and couple relationship length, the results indicated that father-report of PCC predicted increased youth EBPs 12 months later (T1→T2 and T2→T3). In addition, father-report of youth EBPs predicted increased PCC 12 months later (T3→T4). Mother-report did not demonstrate cross-lagged effects. The findings suggest that fathers' perceptions of PCC and youth emotional and behavioral functioning are transactionally related, highlighting the need for family-wide interventions.

Management of Keratoconus in Down Syndrome and Other Intellectual Disability.

The purpose of this study was to assess an intellectual disability (ID) cohort with keratoconus (KC) regarding ophthalmic (visual acuity and corneal tomography) and systemic characteristics and to describe an appropriate clinical algorithm for investigation and management of KC in this setting. This was the retrospective cohort study of patients with ID (Down syndrome, autism, and other) in the cornea department of a tertiary referral ophthalmic hospital in Dublin, Ireland. Retrospective chart review was conducted on people with ID undergoing examination under anesthesia or crosslinking under general anesthetic. Key outcome data included corneal examination findings, corneal tomography, visual acuity, and examination findings (eg, type of ID, general anesthetic, and cardiac status). Mean age of the 24 patients was 31.9 years (66.7% male). ID type was Down syndrome (66.7%), autism (25%), and other (8.3%). KC was diagnosed in 98% of eyes, with 45.8% having untreatable advanced disease (57.1% of these bilateral), 39.6% amenable to corneal collagen crosslinking (35.7% of these bilateral), and 6.3% having corneal transplantation. Congenital heart defects were present in 37.5% of the Down syndrome group. There were no serious ocular or systemic adverse events. KC is strikingly prevalent in the ID population. Ireland has the highest rate of Down syndrome in Europe (26.3:10,000 live births). This group is rarely suitable for corneal transplantation, and corneal collagen crosslinking is an effective intervention to prevent progression to advanced KC in this already socially restricted group. We propose an algorithm for investigation/treatment and also recommend uniform pediatric KC screening/treatment in ID populations.

Racial and ethnic disparities in benefits eligibility and spending among adults on the autism spectrum: A cohort study using the Medicare Medicaid Linked Enrollees Analytic Data Source.

Research on children and youth on the autism spectrum reveal racial and ethnic disparities in access to healthcare and utilization, but there is less research to understand how disparities persist as autistic adults age. We need to understand racial-ethnic inequities in obtaining eligibility for Medicare and/or Medicaid coverage, as well as inequities in spending for autistic enrollees under these public programs. We conducted a cross-sectional cohort study of U.S. publicly-insured adults on the autism spectrum using 2012 Medicare-Medicaid Linked Enrollee Analytic Data Source (n = 172,071). We evaluated differences in race-ethnicity by eligibility (Medicare-only, Medicaid-only, Dual-Eligible) and spending. The majority of white adults (49.87%) were full-dual eligible for both Medicare and Medicaid. In contrast, only 37.53% of Black, 34.65% Asian/Pacific Islander, and 35.94% of Hispanic beneficiaries were full-dual eligible for Medicare and Medicare, with most only eligible for state-funded Medicaid. Adjusted logistic models controlling for gender, intellectual disability status, costly chronic condition, rural status, county median income, and geographic region of residence revealed that Black beneficiaries were significantly less likely than white beneficiaries to be dual-eligible across all ages. Across these three beneficiary types, total spending exceeded $10 billion. Annual total expenditures median expenditures for full-dual and Medicaid-only eligible beneficiaries were higher among white beneficiaries as compared with Black beneficiaries. Public health insurance in the U.S. including Medicare and Medicaid aim to reduce inequities in access to healthcare that might exist due to disability, income, or old age. In contrast to these ideals, our study reveals that racial-ethnic minority autistic adults who were eligible for public insurance across all U.S. states in 2012 experience disparities in eligibility for specific programs and spending. We call for further evaluation of system supports that promote clear pathways to disability and public health insurance among those with lifelong developmental disabilities.

Health status of Medicare-enrolled autistic older adults with and without co-occurring intellectual disability: An analysis of inpatient and institutional outpatient medical claims.

Little is known about the extent to which the healthcare needs of autistic older adults with intellectual disability differ from autistic older adults without intellectual disability. Our study is the first, to our knowledge, to use US national data to compare physical and mental health conditions among autistic older adults with and without intellectual disability. The data analyzed in this study consisted of records from inpatient hospitalizations as well as "institutional outpatient" healthcare visits, which include visits to hospital outpatient departments, rural health clinics, renal dialysis facilities, outpatient rehabilitation facilities, Federally Qualified Health Centers, and community mental health centers. Autistic older adults with intellectual disability were significantly more likely to have thyroid disorders, epilepsy, respiratory infections, gastrointestinal conditions, osteoporosis, cognitive disorders, and schizophrenia/psychotic disorders. In contrast, autistic older adults without intellectual disability were significantly more likely to have obesity, diabetes, high blood pressure, cerebrovascular disease, chronic obstructive pulmonary disease, arthritis, back conditions, attention deficit disorders, substance use disorders, and suicidal ideation or intentional self-injury. These findings highlight the importance of developing distinct, tailored health management strategies for the autistic older adults with and without intellectual disability.

ARTICLE: Determining Intellectual Disability in Death Penalty Cases: A State-by-State Analysis

In Moore v. Texas (2017), the U.S. Supreme Court ruled that Texas death penalty definitions of intellectual disability were inadequate because they strayed too far from clinical definitions. This study examines how each state defines intellectual disability with regard to death penalty eligibility. It reveals a wide variation in the standards used by states, with no clear consensus on definitions of intellectual disability or who should measure it. Variations pertain to age at onset, proof of intellectual disability status at the time of the crime, burden of proof required to make the intellectual disability determination, and who makes the final decision. Implications and suggestions for the future are discussed.

Work, living, and the pursuit of happiness: Vocational and psychosocial outcomes for young adults with autism.

It is important to better understand how adults with autism are functioning in adulthood. Studies that have tracked individuals across the lifespan can help identify developmental factors influence differences in adult outcomes. The present study examines the independence, well-being, and functioning of 123 adults that have been closely followed since early childhood. Autism diagnosis and cognitive assessments were given frequently throughout childhood and during adulthood. We examined differences between adults who had received an autism diagnosis at some point with higher cognitive abilities (Ever ASD-High IQ) and lower cognitive abilities (Ever ASD-Low IQ), as well as adults who never received a diagnosis of autism in the course of the study (Never ASD). We found that autistic features specifically related to adaptive skills and friendships, and verbal intelligence related to work outcomes. In many ways, the Never ASD group had similar outcomes compared to the ASD groups. However, adults with ASD tended to have lower well-being and fewer positive emotions. Families played a major role in supporting adults with and without ASD at all intellectual levels. The findings suggest that realistic ways of increasing independence need to be developed by working with adults and their families, while acknowledging the contribution of individual differences in mental health, intelligence and autism symptoms across neurodevelopmental disorders.

Psychological well-being of fathers with and without a child with intellectual disability: a population-based study.

BackgroundFew studies have explored the well‐being of fathers of children with intellectual disability (ID), despite the significant role that they play in their children's lives. The current study compared fathers of children with and without a child with ID on measures of psychological well‐being (life satisfaction, work–family balance and general health) and dimensions of parenting (parenting self‐efficacy and parent–child closeness) and then examined whether the presence of a child with ID in the family was a significant predictor of paternal well‐being when controlling for a number of father (age, education, employment and residency), child (ID status, gender, behavioural and emotional problems) and family (income poverty and number of children in the household) variables.MethodsData were drawn from the third wave of the Millennium Cohort Study, a UK population‐representative and cohort study, where the cohort child was 5 years of age; 256 fathers were identified as having a child with ID, with data available for 10 187 fathers without a child with ID. Fathers were compared on the four well‐being and parenting outcomes and then multiple regression models were conducted to explore associations between these outcomes and variables identified as potential correlates of well‐being.ResultsInitial group comparisons showed that there were differences in the well‐being of fathers, with fathers of children with ID reporting poorer life satisfaction and general health. However, these differences were small. Regression analyses showed that child behavioural and emotional problems, living in income poverty and paternal employment were more important than disability status in predicting fathers' well‐being.ConclusionsThese works add to the limited amount of research on fathers using population‐representative data. The current findings are consistent with rejecting a general simplistic and negative narrative that raising a child with ID puts fathers at risk of poorer outcomes. However, some fathers, such as those with children with behavioural problems and living in poverty, may require greater support. Future longitudinal research that explores the impact of paternal well‐being on the long‐term outcomes of children with and without ID is warranted.

A Factorial Survey Investigating the Effect of Disclosing Parental Intellectual Disability on Risk Assessments by Children's Social Workers in Child Safeguarding Scenarios.

Literature suggests that, as parents, people with intellectual disabilities experience disproportionately high rates of child removal compared to other groups. A factorial survey of 191 children’s social workers investigated the effect of disclosing parental intellectual disability (ID) upon risk assessments in a range of hypothetical child safeguarding scenarios. The case scenarios depicted a range of child safeguarding situations and parents’ ID status was randomly included as an additional item of information. The data were fitted into a generalised ordinal logistic regression model. Findings indicate that when presented with scenarios considered to be less risky, the parental ID disclosure contributed significantly to a higher risk assessment score. However, when presented with scenarios that were considered more risky, the additional parental ID disclosure did not significantly contribute to a higher score. These findings indicate that the risk associated with parental ID is not fixed but relative to the situation in which it is encountered. The research concludes that in cases of low risk, the effect of parental ID is identified as a support need, whereas the lesser contribution of the disclosure to assessments of higher risk cases may indicate that parental ID is overlooked.

The physical and mental health of middle aged and older adults on the autism spectrum and the impact of intellectual disability

BackgroundPeople on the autism spectrum may have more physical and mental health conditions in midlife and old age compared to the general population. This study describes the physical and mental health of a unique sample of all middle aged and older Wisconsin Medicaid beneficiaries with an autism spectrum disorder diagnosis and tests differences between those with and without co-occurring intellectual disability. MethodUsing de-identified Medicaid claims data for 143 adults with a recorded autism spectrum disorder diagnosis aged 40–88 years with any Wisconsin Medicaid claims in 2012 through 2015, we extracted diagnoses for physical and mental health conditions from fee-for-service claims. Logistic regression analyses—controlling for sex, race, and age—compared the adjusted odds of physical and mental health conditions for those with and without intellectual disability. ResultsMany physical and mental health conditions, including immune conditions (70.6%), cardiovascular disease (49.0%) and its risk factors (46.2%), sleep disorders (85.3%), gastrointestinal disorders (49.7%), neurologic conditions (55.9%), and psychiatric disorders (72.0%) were highly prevalent in our full sample. Although there were many similarities between those individuals with and without co-occurring intellectual disability, middle aged and older adults on the autism spectrum had higher prevalence of epilepsy and lower prevalence of depression and anxiety compared to those without co-occurring intellectual disability. ConclusionsFindings suggest that people on the autism spectrum have a high prevalence of physical and mental health conditions in midlife and old age, regardless of intellectual disability status.

Multimorbidity and lifestyle factors among adults with intellectual disabilities: a cross-sectional analysis of a UK cohort.

Multimorbidity [two or more conditions in addition to intellectual disability (ID)] is known to be more common among people with ID. However, the relationship between multimorbidity and lifestyle factors is currently unknown. The aim of this study was to determine the prevalence of multimorbidity in a population of adults with ID. We also aimed to identify risk factors, including lifestyle factors, for multimorbidity in this population. This was a cross-sectional analysis using data from a diabetes screening study of 920 adults aged 18-74years with ID living in Leicestershire, UK. We described comorbidities and the prevalence of multimorbidity in this population. We explored the relationship between multimorbidity and age, gender, ethnicity, severity of ID, socio-economic status, physical activity, sedentary behaviour, fruit and vegetable consumption and smoking status using multiple logistic regression. The prevalence of multimorbidity was 61.2% (95% CI 57.7-64.7). Multimorbidity was independently associated with being female (P<0.001) and severe/profound ID (P=0.004). Increasing age was of borderline significance (P=0.06). Individuals who were physically inactive or sedentary were more likely to be multimorbid, independent of ability to walk, age, gender, severity of ID, ethnicity and socio-economic status (adjusted OR=1.91; 95% CI 1.23-2.97; P=0.004 and OR=1.98; 95% CI 1.42-2.77; P<0.001). After excluding probable life-long conditions (autism spectrum conditions, attention deficit hyperactivity disorders, epilepsy, cerebral palsy and other paralytic syndromes) as contributing comorbidities, the effect of sedentary behaviour, but not physical activity, remained (P=0.004). We did not observe a relationship between multimorbidity, fruit and vegetable consumption and smoking status. Multimorbidity presents a significant burden to people with ID. Individuals who were physically inactive or sedentary were more likely to be multimorbid, but further work is recommended to explore the relationship between multimorbidity and lifestyle factors using standardised objective measures.

Intellectual disability and mental disorders in a US population representative sample of adolescents.

Most research on the prevalence, distribution, and psychiatric comorbidity of intellectual disability (ID) relies on clinical samples, limiting the generalizability and utility of ID assessment in a legal context. This study assessed ID prevalence in a population-representative sample of US adolescents and examined associations of ID with socio-demographic factors and mental disorders. Data were drawn from the National Comorbidity Survey Adolescent Supplement (N = 6256). ID was defined as: (1) IQ ⩽ 76, measured using the Kaufman Brief Intelligence Test; (2) an adaptive behavior score ⩽76, and (3) age of onset ⩽18 measured using a validated scale. The Composite International Diagnostic Interview assessed 15 lifetime mental disorders. The Sheehan disability scale assessed disorder severity. We used logistic regression models to estimate differences in lifetime disorders for adolescents with and without ID. ID prevalence was 3.2%. Among adolescents with ID, 65.1% met lifetime criteria for a mental disorder. ID status was associated with specific phobia, agoraphobia, and bipolar disorder, but not behavior disorders after adjustment for socio-demographics. Adolescents with ID and mental disorders were significantly more likely to exhibit severe impairment than those without ID. These findings highlight how sample selection and overlap between ID and psychopathology symptoms might bias understanding of the mental health consequences of ID. For example, associations between ID and behavior disorders widely reported in clinical samples were not observed in a population-representative sample after adjustment for socio-demographic confounders. Valid assessment and understanding of these constructs may prove influential in the legal system by influencing treatment referrals and capital punishment decisions.General Scientific SummaryCurrent definitions of intellectual disability (ID) are based on three criteria: formal designation of low intelligence through artificial problem-solving tasks, impairment in one's ability to function in his/her social environment, and early age of onset. In a national population sample of adolescents, the majority of those with ID met criteria for a lifetime mental disorder. Phobias and bipolar disorder, but not behavior disorders, were elevated in adolescents with ID. Findings highlight the need to consider how behavioral problems are conceptualized and classified in people with ID.

The association between employment status and health among British adults with and without intellectual impairments: cross-sectional analyses of a cohort study

BackgroundThere exists a well established link between employment status and health, with unemployment being associated with poorer health. Much less is known about the association between economic inactivity and health, especially among people with disabilities. Our aim is to determine whether the association between employment status and health is similar for adults with and adults without intellectual impairment.MethodsUsing nationally representative data from the 1970 British Cohort Study, we undertook a series of cross sectional analyses of the association between employment status and health (self-reported general health, mental health) among British adults with and without intellectual impairments at ages 26, 30, 34, 38 and 42.ResultsPeople with intellectual disability and borderline intellectual functioning had markedly lower employment rates and poorer health than other participants at all waves of data collection. When compared with participants in full-time employment the prevalence of poorer self rated health and mental health was higher among participants with and without intellectual impairment who were in either part-time employment or were economically inactive at all ages. When compared with participants in employment the prevalence of poorer self rated health and mental health was higher among participants with and without intellectual impairment who were in the economically inactive categories of unemployment, education/training and ill/disabled at all ages. Intellectual disability status appeared to moderate the strength of the relationship between economic activity and self-rated health and, to a much lesser extent, the relationship between economic activity and mental health. In all instances the moderation indicated a stronger association among participants without intellectual impairment.ConclusionsThe results provide substantive evidence to suggest that the nature of the well-established association between employment and better health is similar for British adults with and without intellectual impairments. The results do, however, indicate that the magnitude of the effect involved differed. Further research is needed to identify mechanisms that may underlie this difference.

Pathways from Birth Weight to ADHD Symptoms through Fluid Reasoning in Youth with or without Intellectual Disability.

Although individual differences in fluid reasoning reliably mediate predictions of attention-deficit/hyperactivity disorder (ADHD) symptoms from birth weight in youth with typical cognitive development (TD), it is unknown if this indirect effect operates similarly in the development of ADHD symptoms secondary to intellectual disability (ID). Thus, we evaluated mediation by fluid reasoning in a longitudinal sample of 163 youth (45% female) with (n=52) or without (n=111) ID who were followed prospectively from age 5 to age 13. At age 9, youth completed the Arithmetic subtest of the Wechsler Intelligence Scale for Children, a measure of fluid reasoning. At ages 9 and 13, mothers and teachers separately rated youth ADHD symptoms and mothers completed a diagnostic interview. Mediation was tested via path analysis with bootstrapped confidence intervals, and moderated mediation estimated whether indirect effects differed between ID and TD youth or based on youth IQ. Controlling for demographic factors and age 9 ADHD symptoms, age 9 Arithmetic mediated birth weight and multi-method/informant age 13 ADHD symptoms, such that birth weight positively predicted Arithmetic, which negatively predicted ADHD symptoms. Neither ID status nor IQ moderated the observed indirect effect through Arithmetic, suggesting that it was similar for ID and TD youth as well as across the range of youth IQs. These findings support previous evidence that fluid reasoning, as measured by Arithmetic, may causally mediate birth weight and ADHD symptoms, and suggest that this pathway operates similarly with respect to the development of ADHD symptoms in youth with ID.