Umbrella systematic review of systematic reviews and meta-analyses on comorbid physical conditions in people with autism spectrum disorder.

BACKGROUND: Comorbid physical conditions may be more common in people with autism spectrum disorder (ASD) than other people. AIMS: To identify what is and what is not known about comorbid physical conditions in people with ASD. METHOD: We undertook an umbrella systematic review of systematic reviews and meta-analyses on comorbid physical conditions in people with ASD. Five databases were searched. There were strict inclusion/exclusion criteria. We undertook double reviewing for eligibility, systematic data extraction and quality assessment. Prospective PROSPERO registration: CRD42015020896. RESULTS: In total, 24 of 5552 retrieved articles were included, 15 on children, 1 on adults, and 8 both on children and adults. Although the quality of included reviews was good, most reported several limitations in the studies they included and considerable heterogeneity. Comorbid physical conditions are common, and some are more prevalent than in the general population: sleep problems, epilepsy, sensory impairments, atopy, autoimmune disorders and obesity. Asthma is not. However, there are substantial gaps in the evidence base. Fewer studies have been undertaken on other conditions and some findings are inconsistent. CONCLUSIONS: Comorbid physical conditions occur more commonly in people with ASD, but the evidence base is slim and more research is needed. Some comorbidities compound care if clinicians are unaware, for example sensory impairments, given the communication needs of people with ASD. Others, such as obesity, can lead to an array of other conditions, disadvantages and early mortality. It is essential that potentially modifiable physical conditions are identified to ensure people with ASD achieve their best outcomes. Heightening clinicians' awareness is important to aid in assessments and differential diagnoses, and to improve healthcare.

The relative influence of intellectual disabilities and autism on sensory impairments and physical disability: A whole-country cohort of 5.3 million children and adults.

BACKGROUND: Intellectual disabilities and autism are lifelong and often co-occur. Little is known on their extent of independent association with sensory impairments and physical disability. METHODS: For Scotland's population, logistic regressions investigated age-gender-adjusted odds ratios (OR) of associations, independently, of intellectual disabilities and autism with sensory impairments and physical disability. RESULTS: 1,548,819 children/youth, and 3,746,584 adults. In children/youth, the effect size of intellectual disabilities and autism, respectively, was as follows: blindness (OR = 30.12; OR = 2.63), deafness (OR = 13.98; OR = 2.31), and physical disability (OR = 43.72; OR = 5.62). For adults, the effect size of intellectual disabilities and autism, respectively, was as follows: blindness (OR = 16.89; OR = 3.29), deafness (OR = 7.47; OR = 2.36), and physical disability (OR = 6.04; OR = 3.16). CONCLUSIONS: Intellectual disabilities have greater association with the population burden of sensory impairments/physical disability, but autism is also associated regardless of overlap with intellectual disabilities. These may impact further on communication limitations due to autism and intellectual disabilities, increasing complexity of assessments/management of other health conditions. Clinicians need to be aware of these important issues.

General health status of youth with autism with and without intellectual disabilities transitioning from special education, and its relationship to personal and family circumstances: longitudinal cohort study.

Objective: Transition from school to early adulthood incurs many changes and may be associated with deterioration in general health in youth with autism. We aimed to investigate this. Method: The National Longitudinal Transitions Study-2 is a USA nationally representative sample of youth receiving special education services, aged 13-17 at wave 1, followed-up over 10 years in five data collection waves. We conducted random-effects ordered logistic regressions to determine the odds ratios (OR) with 95% confidence intervals of wave, age, sex, ethnicity/race, additional intellectual disabilities, parental/guardian relationship status, and household income being associated with general health status in youth with autism. Results: Across waves, only between 74.3%-69.6% had excellent/very good health (71.7%-58.8% in those with co-occurring intellectual disabilities), but wave was not associated with health status. Associations were with age OR = 1.18 (1.04, 1.33), co-occurring intellectual disabilities OR = 1.56 (1.00, 2.44), and household income OR = 0.61 (0.40, 0.94) at $30,001-$50,000, OR = 0.44 (0.27, 0.72) at $50,001-$70,000, and OR = 0.34 (0.20, 0.56) at $70,001+. Sex, ethnicity/race, and parental/guardian relationship status were not associated with health status. Conclusion: There was little change in general health status longitudinally across the transitional period, but the proportion with excellent/very good health was low at each wave. Transitional planning should consider co-occurring intellectual disabilities, and the wider socioeconomic context in which children/youth with autism are raised. Lack of other longitudinal studies indicates a need for replication.

Cohort profile: Scotland's record-linkage e-cohorts of people with intellectual disabilities, and autistic people (SCIDA).

PURPOSE: To investigate health, mortality and healthcare inequalities experienced by people with intellectual disabilities, and autistic people, and their determinants; an important step towards identifying and implementing solutions to reduce inequalities. This paper describes the cohorts, record-linkages and variables that will be used. PARTICIPANTS: Scotland's Census, 2011 was used to identify Scotland's citizens with intellectual disabilities, and autistic citizens, and representative general population samples with neither. Using Scotland's community health index, the Census data (demography, household, employment, long-term conditions) were linked with routinely collected health, death and healthcare data: Scotland's register of deaths, Scottish morbidity data 06 (SMR06: cancer incidence, mortality, treatments), Prescribing Information System (identifying asthma/chronic obstructive pulmonary disease; angina/congestive heart failure/hypertension; peptic ulcer/reflux; constipation; diabetes; thyroid disorder; depression; bipolar disorders; anxiety/sleep; psychosis; attention deficit hyperactivity disorder; epilepsy; glaucoma), SMR01 (general/acute hospital admissions and causes, ambulatory care sensitive admissions), SMR04 (mental health admissions and causes), Scottish Care Information-Diabetes Collaboration (diabetic care quality, diabetic outcomes), national bowel screening programme and cervical screening. FINDINGS TO DATE: Of the whole population, 0.5% had intellectual disabilities, and 0.6% were autistic. Linkage was successful for >92%. The resultant e-cohorts include: (1) 22 538 people with intellectual disabilities (12 837 men and 9701 women), 4509 of whom are children <16 years, (2) 27 741 autistic people (21 390 men and 6351 women), 15 387 of whom are children <16 years and (3) representative general population samples with neither condition. Very good general health was reported for only 3389 (15.0%) people with intellectual disabilities, 10 510 (38.0%) autistic people, compared with 52.4% general population. Mental health conditions were reported for 4755 (21.1%) people with intellectual disabilities, 3998 (14.4%) autistic people, compared with 4.2% general population. FUTURE PLANS: Analyses will determine the extent of premature mortality, causes of death, and avoidable deaths, profile of health conditions and cancers, healthcare quality and screening and determinants of mortality and healthcare.

Rates, causes and predictors of all-cause and avoidable mortality in 163 686 children and young people with and without intellectual disabilities: a record linkage national cohort study.

OBJECTIVES: To investigate mortality rates and associated factors, and avoidable mortality in children/young people with intellectual disabilities. DESIGN: Retrospective cohort; individual record-linked data between Scotland's 2011 Census and 9.5 years of National Records for Scotland death certification data. SETTING: General community. PARTICIPANTS: Children and young people with intellectual disabilities living in Scotland aged 5-24 years, and an age-matched comparison group. MAIN OUTCOME MEASURES: Deaths up to 2020: age of death, age-standardised mortality ratios (age-SMRs); causes of death including cause-specific age-SMRs/sex-SMRs; and avoidable deaths. RESULTS: Death occurred in 260/7247 (3.6%) children/young people with intellectual disabilities (crude mortality rate=388/100 000 person-years) and 528/156 439 (0.3%) children/young people without intellectual disabilities (crude mortality rate=36/100 000 person-years). SMRs for children/young people with versus those without intellectual disabilities were 10.7 for all causes (95% CI 9.47 to 12.1), 5.17 for avoidable death (95% CI 4.19 to 6.37), 2.3 for preventable death (95% CI 1.6 to 3.2) and 16.1 for treatable death (95% CI 12.5 to 20.8). SMRs were highest for children (27.4, 95% CI 20.6 to 36.3) aged 5-9 years, and lowest for young people (6.6, 95% CI 5.1 to 8.6) aged 20-24 years. SMRs were higher in more affluent neighbourhoods. Crude mortality incidences were higher for the children/young people with intellectual disabilities for most International Statistical Classification of Diseases and Related Health Problems, 10th Revision chapters. The most common underlying avoidable causes of mortality for children/young people with intellectual disabilities were epilepsy, aspiration/reflux/choking and respiratory infection, and for children/young people without intellectual disabilities were suicide, accidental drug-related deaths and car accidents. CONCLUSION: Children with intellectual disabilities had significantly higher rates of all-cause, avoidable, treatable and preventable mortality than their peers. The largest differences were for treatable mortality, particularly at ages 5-9 years. Interventions to improve healthcare to reduce treatable mortality should be a priority for children/young people with intellectual disabilities. Examples include improved epilepsy management and risk assessments, and coordinated multidisciplinary actions to reduce aspiration/reflux/choking and respiratory infection. This is necessary across all neighbourhoods.

Respiratory-associated deaths in people with intellectual disabilities: a systematic review and meta-analysis.

OBJECTIVE: To review and synthesise evidence on rates of respiratory-associated deaths and associated risk factors in the intellectual disability population. DESIGN: Systematic review and meta-analysis. DATA SOURCES: Embase, CINAHL, ISI Web of Science (all databases including Medline) and PsychINFO were searched for studies published between 1st January 1985 and 27th April 2020 and examined study and outcome quality. Reference lists and Google Scholar were also hand searched. RESULTS: We identified 2295 studies, 17 were included in the narrative synthesis and 10 studies (11 cohorts) in the meta-analysis. Data from 90 302 people with intellectual disabilities and 13 808 deaths from all causes in people with intellectual disabilities were extracted. Significantly higher rates of respiratory-associated deaths were found among people with intellectual disabilities (standardised mortality ratio(SMR): 10.86 (95% CI: 5.32 to 22.18, p<0.001) compared with those in the general population, lesser rates for adults with ID (SMR: 6.53 (95% CI: 4.29 to 9.96, p<0.001); and relatively high rates from pneumonia 26.65 (95% CI: 5.63 to 126.24, p<0.001). The overall statistical heterogeneity was I2=99.0%. CONCLUSION: Premature deaths due to respiratory disorders are potentially avoidable with improved public health initiatives and equitable access to quality healthcare. Further research should focus on developing prognostic guidance and validated tools for clinical practice to mitigate risks of respiratory-associated deaths. PROSPERO REGISTRATION NUMBER: CRD42020180479.

Prevalence of mental health conditions, sensory impairments and physical disability in people with co-occurring intellectual disabilities and autism compared with other people: a cross-sectional total population study in Scotland.

OBJECTIVES: To investigate prevalence of mental health conditions, sensory impairments and physical disability in children, adults and older adults with co-occurring intellectual disabilities and autism, given its frequent co-occurrence, compared with the general population. DESIGN: Whole country cohort study. SETTING: General community. PARTICIPANTS: 5709 people with co-occurring intellectual disabilities and autism, compared with 5 289 694 other people. OUTCOME MEASURES: Rates and ORs with 95% CIs for mental health conditions, visual impairment, hearing impairment and physical disability in people with co-occurring intellectual disabilities and autism compared with other people, adjusted for age, sex and interaction between age and co-occurring intellectual disabilities and autism. RESULTS: All four long-term conditions were markedly more common in children, adults and older adults with co-occurring intellectual disabilities and autism compared with other people. For mental health, OR=130.8 (95% CI 117.1 to 146.1); visual impairment OR=65.9 (95% CI 58.7 to 73.9); hearing impairment OR=22.0 (95% CI 19.2 to 25.2); and physical disability OR=157.5 (95% CI 144.6 to 171.7). These ratios are also greater than previously reported for people with either intellectual disabilities or autism rather than co-occurring intellectual disabilities and autism. CONCLUSIONS: We have quantified the more than double disadvantage for people with co-occurring intellectual disabilities and autism, in terms of additional long-term health conditions. This may well impact on quality of life. It raises challenges for staff working with these people in view of additional complexity in assessments, diagnoses and interventions of additional health conditions, as sensory impairments and mental health conditions in particular, compound with the persons pre-existing communication and cognitive problems in this context. Planning is important, with staff being trained, equipped, resourced and prepared to address the challenge of working for people with these conditions.

Relative influence of intellectual disabilities and autism on mental and general health in Scotland: a cross-sectional study of a whole country of 5.3 million children and adults.

OBJECTIVES: To determine the relative extent that autism and intellectual disabilities are independently associated with poor mental and general health, in children and adults. DESIGN: Cross-sectional study. For Scotland's population, logistic regressions investigated odds of intellectual disabilities and autism predicting mental health conditions, and poor general health, adjusted for age and gender. PARTICIPANTS: 1 548 819 children/youth aged 0-24 years, and 3 746 584 adults aged more than 25 years, of whom 9396/1 548 819 children/youth had intellectual disabilities (0.6%), 25 063/1 548 819 children/youth had autism (1.6%); and 16 953/3 746 584 adults had intellectual disabilities (0.5%), 6649/3 746 584 adults had autism (0.2%). These figures are based on self-report. MAIN OUTCOME MEASURES: Self-reported general health status and mental health. RESULTS: In children/youth, intellectual disabilities (OR 7.04, 95% CI 6.30 to 7.87) and autism (OR 25.08, 95% CI 23.08 to 27.32) both independently predicted mental health conditions. In adults, intellectual disabilities (OR 3.50, 95% CI 3.20 to 3.84) and autism (OR 5.30, 95% CI 4.80 to 5.85) both independently predicted mental health conditions. In children/youth, intellectual disabilities (OR 18.34, 95% CI 17.17 to 19.58) and autism (OR 8.40, 95% CI 8.02 to 8.80) both independently predicted poor general health. In adults, intellectual disabilities (OR 7.54, 95% CI 7.02 to 8.10) and autism (OR 4.46, 95% CI 4.06 to 4.89) both independently predicted poor general health. CONCLUSIONS: Both intellectual disabilities and autism independently predict poor health, intellectual disabilities more so for general health and autism more so for mental health. Intellectual disabilities and autism are not uncommon, and due to their associated poor health, sufficient services/supports are needed. This is not just due to coexistence of these conditions or just to having intellectual disabilities, as the population with autism is independently associated with substantial health inequalities compared with the general population, across the entire life course.

Prevalence of sensory impairments, physical and intellectual disabilities, and mental health in children and young people with self/proxy-reported autism: Observational study of a whole country population.

This study investigated the comorbid conditions in a whole country population of children/young people aged 0-24 years with and without autism. Data were drawn from Scotland's Census 2011. We calculated the percentage with autism, their extent of comorbid conditions, odds ratio (with 95% confidence intervals) of autism predicting comorbidities, adjusted for age and gender, and odds ratio for age and gender predicting comorbidities within the cohort with autism. A total of 25,063/1,548,819 (1.6%) had autism: 19,880 (79.3%) males and 5183 (20.7%) females. Autism had an odds ratio of 5.4 (5.1-5.6) for predicting deafness/partial hearing loss, odds ratio of 8.9 (8.1-9.7) for blindness/partial sight loss, odds ratio of 49.7 (38.1-64.9) for intellectual disabilities, odds ratio of 15.7 (13.4-18.5) for mental health conditions, odds ratio of 15.8 (14.1-17.8) for physical disability and odds ratio of 3.9 (3.8-4.0) for other conditions. Females with autism were more likely to have each additional condition than males, including intellectual disabilities, suggesting they may have more severe autism than males and adding evidence that autism may be currently underdiagnosed in more intellectually able females. These conditions are disabling and have a significant impact on long-term quality of life; their coexistence with autism adds extra complexity. It is important to raise clinicians' awareness of this extent of comorbidity, and to have accurate prevalence data to plan prevention and intervention measures, and to follow health inequality trends.

Age at identification, prevalence and general health of children with autism: observational study of a whole country population.

OBJECTIVES: Reported childhood prevalence of autism varies considerably between studies and over time, and general health status has been little investigated. We aimed to investigate contemporary prevalence of reported autism by age, and general health status of children/young people with and without autism. DESIGN: Secondary analysis of Scotland's Census, 2011 data. Cross-sectional study. SETTING: General population of Scotland. PARTICIPANTS: All children (n=916 331) and young people (n=632 488) in Scotland. MAIN OUTCOME MEASURES: Number (%) of children/young people reported to have autism and their general health status; prevalence of autism; prevalence of poor health (fair, bad and very bad health); odds ratios (95% confidence intervals) of autism predicting poor health, adjusted for age and gender and OR for age and gender in predicting poor health within the population with reported autism. RESULTS: Autism was reported for 17 348/916 331 (1.9%) children aged 0-15, and 7715/632 488 (1.2%) young people aged 16-24. The rate increased to age 11 in boys and age 10 in girls, reflecting age at diagnosis. Prevalence was 2.8% at age 10 (4.4% for boys; 1.1% for girls), and 2.9% at age 11 (4.5% for boys; 1.1% for girls). 22.0% of children and 25.5% of young people with autism reported poor health, compared with 2.0% and 4.4% without autism. Autism had OR=11.3 (11.0 to 11.7) in predicting poor health. Autistic females had poorer health than autistic males, OR=1.6 (1.5 to 1.8). CONCLUSION: Accurate information on the proportion of autistic children and their health status is essential plan appropriate prevention and intervention measures and provide resources for those who may put demand on services designed for autistic people.

Prevalence of long-term health conditions in adults with autism: observational study of a whole country population.

OBJECTIVES: To investigate the prevalence of comorbid mental health conditions and physical disabilities in a whole country population of adults aged 25+ with and without reported autism. DESIGN: Secondary analysis of Scotland's Census, 2011 data. Cross-sectional study. SETTING: General population. PARTICIPANTS: 94% of Scotland's population, including 6649/3 746 584 adults aged 25+ reported to have autism. MAIN OUTCOME MEASURES: Prevalence of six comorbidities: deafness or partial hearing loss, blindness or partial sight loss, intellectual disabilities, mental health conditions, physical disability and other condition; ORs (95% CI) of autism predicting these comorbidities, adjusted for age and gender; and OR for age and gender in predicting comorbidities within the population with reported autism. RESULTS: Comorbidities were common: deafness/hearing loss-14.1%; blindness/sight loss-12.1%; intellectual disabilities-29.4%; mental health conditions-33.0%; physical disability-24.0%; other condition-34.1%. Autism statistically predicted all of the conditions: OR 3.3 (95% CI 3.1 to 3.6) for deafness or partial hearing loss, OR 8.5 (95% CI 7.9 to 9.2) for blindness or partial sight loss, OR 94.6 (95% CI 89.4 to 100.0) for intellectual disabilities, OR 8.6 (95% CI 8.2 to 9.1) for mental health conditions, OR 6.2 (95% CI 5.8 to 6.6) for physical disability and OR 2.6 (95% CI 2.5 to 2.8) for other condition. Contrary to findings within the general population, female gender predicted all conditions within the population with reported autism, including intellectual disabilities (OR=1.4). CONCLUSIONS: Clinicians need heightened awareness of comorbidities in adults with autism to improve detection and suitable care, especially given the added complexity of assessment in this population and the fact that hearing and visual impairments may cause additional difficulties with reciprocal communication which are also a feature of autism; hence posing further challenges in assessment.

Prevalence and general health status of people with intellectual disabilities in Scotland: a total population study.

BACKGROUND: Prevalence of intellectual disabilities varies considerably between studies. People with intellectual disabilities experience health inequalities, but most studies comprise small or incomplete populations. We investigated in a whole country population the (1) prevalence of intellectual disabilities and (2) general health status compared with the general population. METHOD: Data were from Scotland's Census, 2011. We calculated the prevalence of intellectual disabilities, reported general health status of people with and without intellectual disabilities and the extent of health-related limitations to daily activities. We conducted logistic regressions to determine the ORs of intellectual disabilities predicting poor health and associations with age and gender. RESULTS: Of Scotland's 5 295 403 population, 26 349 (0.5%) had intellectual disabilities; 15 149 (57.5%) were males and 11 200 (42.5%) were females; 5234 (0.6%) were children/youth (0-15) and 21 115 (0.5%) were adults (16-75+ years). Identification of intellectual disabilities rises until age 5 years, with a further small rise by age 9 years. Children and adults with intellectual disabilities reported more poor health (47.9% and 40.3%) than the general population (2.1% and 13.8%) and were more limited in activities by their health. Intellectual disabilities had an OR of 43.2 (95% CI 40.8 to 45.7) in predicting poor health; the influence of increasing age on poor health was markedly interacted by presence of intellectual disabilities, likely to be due to a 'healthy survivor' effect within the intellectual disabilities population. CONCLUSION: People with intellectual disabilities have poorer general health than other people, especially children and young people. Accurate information on population prevalence and health status is essential to plan appropriate resources.

Prevalence of mental health conditions and relationship with general health in a whole-country population of people with intellectual disabilities compared with the general population.

BACKGROUND: There are no previous whole-country studies on mental health and relationships with general health in intellectual disability populations; study results vary. AIMS: To determine the prevalence of mental health conditions and relationships with general health in a total population with and without intellectual disabilities. METHOD: Ninety-four per cent completed Scotland's Census 2011. Data on intellectual disabilities, mental health and general health were extracted, and the association between them was investigated. RESULTS: A total of 26 349/5 295 403 (0.5%) had intellectual disabilities. In total, 12.8% children, 23.4% adults and 27.2% older adults had mental health conditions compared with 0.3, 5.3 and 4.5% of the general population. Intellectual disabilities predicted mental health conditions; odds ratio (OR)=7.1 (95% CI 6.8-7.3). General health was substantially poorer and associated with mental health conditions; fair health OR=1.8 (95% CI 1.7-1.9), bad/very bad health OR=4.2 (95% CI 3.9-4.6). CONCLUSIONS: These large-scale, whole-country study findings are important, given the previously stated lack of confidence in comparative prevalence results, and the need to plan services accordingly. DECLARATION OF INTEREST: None. COPYRIGHT AND USAGE: © The Royal College of Psychiatrists 2017. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) license.