Data Linkage: Canadian and Australian Perspectives on a Valuable Methodology for Intellectual and Developmental Disability Research

Young adults with intellectual and developmental disabilities who participate in Special Olympics are less likely to be diagnosed with depression

PURPOSE

People with intellectual and developmental disabilities (IDD) experience high rates of depression. Evidence indicates that physical activity, or participation in a sports club, in a supportive social environment has mental and physical health benefits. Adults with IDD, on average, engage in low levels of physical activity. The purpose of this study was to compare the rates of depression among young adult Special Olympics participants with IDD compared to non-participants with IDD.

METHODS

This was a 20-year retrospective cohort study of young adults (19-29 years) with IDD in the province of Ontario, Canada that compared rates of depression among Special Olympics participants (n = 8710) to non-participants (n = 42,393) using administrative health databases housed at ICES (formerly the Institute for Clinical Evaluative Sciences). Using cox proportional hazard models, the crude hazard ratios were calculated for the association between each independent variable and the dependent variable.

RESULTS

After controlling for other variables, the hazard rate for depression among Special Olympics participants compared to the hazard rate for depression among non-participants generated an adjusted hazard ratio of 0.51. Over the 20-year follow-up, the participants were 0.51 times as likely to develop depression as non-participants; this represents a 49% reduction in risk among Special Olympics participants. This result was statistically significant and represents a medium effect size.

CONCLUSION

Future research is needed on how much of this risk reduction is related to a physiological response to physical activity/exercise, and how much is related to the social connectedness of being part of a group participating in Special Olympics.

Population level administrative data evidence of visits to the emergency department by youth with intellectual/developmental disabilities in BC, Canada

INTRODUCTION

The literature indicates that youth with intellectual/developmental disabilities (IDD) have poor health and that access to health services decreases as they transition from pediatric to adult services. At the same time their use of emergency department services increases. The objective of this study was to compare use of emergency department services by youth with IDD to youth without IDD, with particular emphasis on the transition period from pediatric to adult health care services.

METHODS

This research used a population level administrative health data base for the province of British Columbia Canada for 2010-2019 to examine the use of emergency departments by youth with IDD (N = 20,591) compared to a population group of youth without IDD (N = 1,293,791). Using the ten years of data, odds ratios for visits to the emergency department were calculated adjusting for sex, income and geographical area within the Province. In addition, difference-in-differences analyses were calculated for age matched subsets of the two cohorts.

RESULTS

Over the ten year period, 40.60% of youth with IDD visited an emergency department at least once, compared to 29.10% of youth without IDD. Youth with IDD had an odds ratio of visiting an emergency department 1.697 (1.649, 1.747) times that of youth without IDD. However, when odds were adjusted for a diagnosis of either psychotic illness or anxiety/depression, the odds for youth with IDD visiting emergency compared to youth without IDD were reduced to 1.063 (1.031, 1.096). Use of emergency services increased as youth aged. Type of IDD also affected use of emergency services. Youth with Fetal Alcohol Syndrome had the greatest odds of using emergency services compared to youth with other types of IDD.

DISCUSSION

The findings from this study indicate that youth with IDD have higher odds of using emergency services than youth without IDD although these increased odds appear to be largely driven by mental illness. In addition, use of emergency services increases as the youth age and transition from pediatric to adult health services. Better treatment of mental health issues within this population may reduce their use of emergency services.

Intellectual disabilities and autism among children with congenital heart defects, Western Australia, 1983-2010

BACKGROUND

Children with congenital heart defects (CHDs) are at higher risk of developing an intellectual disability. However, severity of intellectual disabilities among this group of children are largely unknown. Our objective was to determine the risk of intellectual disability (ID), ID severity, and autism among children with CHDs.

METHODS

We conducted a retrospective cohort study of singleton live births in Western Australia (n = 20,592) between 1983 and 2010. Children with CHDs were identified from the Western Australian Register for Developmental Anomalies (n = 6563) and infants without CHDs were randomly selected from state birth records (n = 14,029). Children diagnosed with ID before 18 years were identified by linkage to statewide Intellectual Disability Exploring Answers database. Odds ratios (OR) and 95% confidence intervals (CI) were calculated from logistic regression models for all CHDs combined and by CHD severity adjusting for potential confounders.

RESULTS

Of 20,592 children, 466 (7.1%) with CHDs and 187 (1.3%) without CHDs had an ID. Compared to children without CHDs, children with any CHD had 5.26 times (95% CI 4.42, 6.26) the odds of having an ID and 4.76 times (95% CI 3.98, 5.70) the odds of having mild/moderate ID. Children with any CHD had 1.76 times the odds of having autism (95% CI 1.07, 2.88), and 3.27 times the odds of having an unknown cause of ID (95% CI 2.65, 4.05) compared to children without CHD. The risk of having autism (aOR 3.23, 95% CI 1.11, 9.38), and unknown cause of ID (aOR 3.45, 95% CI 2.09, 5.70) was greatest for children with mild CHD.

CONCLUSIONS

Children with CHDs were more likely to have an ID or autism. Future research should elucidate underlying etiology of ID in children with CHDs.

An Examination of Support Needs, Supports, and Outcomes for People With Intellectual and Developmental Disabilities

Researchers used a merged dataset to examine if more resources were expended on those with greater support needs and if support needs impacted personal outcomes when controlling for relevant personal and contextual factors. Results indicated that the amount of support a person receives had a direct relationship to their needs. However, we also found that people with the greatest needs had weaker personal outcomes suggesting that distribution of resources based on need may not result in equivalent outcomes. The authors suggest strategies at an individual and systems level to address the outcomes gap for people with the greatest support needs.

Premature mortality in a population-based cohort of autistic adults in Canada

Research from different countries suggests that autistic adults are more likely to die prematurely than non-autistic adults, but these studies do not always investigate male and female individuals separately and do not consider whether this pattern is unique to autistic people or is also an issue for people with other developmental disabilities. We examined premature mortality in autistic males and females (assigned at birth) in a population-based cohort, compared to males and females with and without other developmental disabilities. Using linked administrative health and social services population data from Ontario, Canada, age-matched males and females aged 19-65 years were followed between 2010 and 2016, and causes of death were determined. Over the 6-year observation period, 330 of 42,607 persons (0.77%) in the group without developmental disabilities had died compared to 259 of 10,646 persons (2.43%) in the autism group and 419 of 10,615 persons (3.95%) in the other developmental disabilities group. Autistic males and females were more likely to die than non-autistic males (adjusted risk ratio, RR 3.13, 95%CI 2.58-3.79) and non-autistic females (adjusted RR 3.12, 95%CI 2.35-4.13) without developmental disabilities, but were less likely to die than adults with other developmental disabilities (males: adjusted RR 0.66, 95%CI 0.55-0.79; females: adjusted RR 0.55, 95%CI 0.43-0.71). Most common causes of death varied depending on a person's sex and diagnosis. Given the greater likelihood of premature mortality in adults with developmental disabilities including autism, greater attention and resources directed toward their health and social care are needed, tailored to their sex and diagnosis-informed needs. LAY SUMMARY: This study looked at how many autistic men and women died over 6 years (2010-2016), along with how they died, and compared this to adults who did not have autism living in Ontario, Canada. It found that autistic men and women were more than three times as likely to die as people of the same age who did not have a developmental disability. However, adults with other developmental disabilities besides autism were even more likely to die than autistic adults. This means that we have to pay more attention and invest in better social and health care for autistic people, along with people who have other types of developmental disabilities.

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.

Intellectual/developmental disabilities among people incarcerated in federal correctional facilities in Ontario, Canada: Examining prevalence, health and correctional characteristics

BACKGROUND

There is little research with people who experience intellectual/developmental disabilities and imprisonment.

METHODS

The study linked health and correctional data to examine prevalence of intellectual/developmental disabilities and health and correctional characteristics among adults experiencing their first federal incarceration between 1 January 2002 and 31 December 2011 (n = 9278) and two non-incarcerated groups (n = 10,086,802).

RESULTS

The prevalence of intellectual/developmental disabilities was 2.1% in the incarcerated group and 0.9% in the non-incarcerated group. Before incarceration, those with, versus without, intellectual/developmental disabilities were at greater risk of traumatic brain injury, mental illness, and substance use disorders. While incarcerated, those with intellectual/developmental disabilities were more likely to incur serious institutional disciplinary charges. Post-incarceration, persons with intellectual/developmental disabilities were at greater risk of emergency department visits, and psychiatric and acute hospitalizations, than the non-incarcerated groups.

CONCLUSIONS

People with intellectual/developmental disabilities are overrepresented in Canadian federal correctional institutions. The authors offer strategies to support people prior to, during, and post-incarceration.

A systematic review of the biological, social, and environmental determinants of intellectual disability in children and adolescents

AIM

This systematic review aimed to identify the most important social, environmental, biological, and/or genetic risk factors for intellectual disability (ID).

METHODS

Eligible were published prospective or retrospective comparative studies investigating risk factors for ID in children 4-18 years. Exclusions were single group studies with no comparator without ID and a sample size <100. Electronic databases (Medline, Cochrane Library, EMBASE, PsycInfo, Campbell Collaboration, and CINAHL) were searched for eligible publications from 1980 to 2020. Joanna Briggs Institute critical appraisal instruments, appropriate for study type, were used to assess study quality and risk of bias. Descriptive characteristics and individual study results were presented followed by the synthesis for individual risk factors, also assessed using GRADE.

RESULTS

Fifty-eight individual eligible studies were grouped into six exposure topics: sociodemographic; antenatal and perinatal; maternal physical health; maternal mental health; environmental; genetic or biological studies. There were few eligible genetic studies. For half the topics, the certainty of evidence (GRADE) was moderate or high.

CONCLUSION

Multiple studies have examined individual potential determinants of ID, but few have investigated holistically to identify those populations most at risk. Our review would indicate that there are vulnerable groups where risk factors we identified, such as low socioeconomic status, minority ethnicity, teenage motherhood, maternal mental illness, and alcohol abuse, may cluster, highlighting a target for preventive strategies. At-risk populations need to be identified and monitored so that interventions can be implemented when appropriate, at preconception, during pregnancy, or after birth. This could reduce the likelihood of ID and provide optimal opportunities for vulnerable infants.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=120032], identifier [CRD42019120032].

Invisible populations: Who is missing from research in intellectual disability?

It is estimated that approximately 41% of adults with intellectual and developmental disability (IDD) are served through the developmental disabilities (DD) system in the US. The remaining 59% include individuals who meet diagnostic criteria but are not actively receiving paid services or may not be known to the DD system. Scholars have referred to this group as the "hidden majority." Very little is known about the health and well-being of these adults. It remains to be seen if the hidden majority is comparably susceptible to mental health difficulties, given how little is known about this population by DD systems. The purpose of this manuscript is to highlight where one may identify individuals belonging to this hidden population and how researchers might effectively recruit from this group so as to ensure more representative samples of all people with IDD.

Health and Access to Health Services for People with Disability in Australia: Data and Data Gaps

The right of people with disability to enjoyment of the highest attainable standard of health without discrimination on the basis of disability is enshrined in the United Nations Convention on the Rights of Persons with Disabilities (CRPD). Among its obligations as a signatory to the CRPD, Australia is required to collect appropriate information, including statistical and research data, to inform development and implementation of policies to give effect to the Convention. In this commentary, we first describe how the International Classification of Functioning, Disability and Health (ICF) conceptual model of disability can be operationalised in statistical data collections, with a focus on how this is achieved in key Australian data sources such that people with disability can be identified as a population group. We then review existing statistical data on health and health service use for people with disability in Australia, highlighting data gaps and limitations. Finally, we outline priorities and considerations for improving data on health and access to health services for people with disability. As well as conceptual, practical, and ethical considerations, a key principle that must guide future disability data development is that people with disability and their representative organisations must be involved and participate fully in the development of disability data and statistics, and in their use.

Rethinking Management Information Systems for Scaling up Employment Outcomes

People with intellectual disability, autism, and other developmental disabilities have successfully demonstrated their ability to work in the general labor market. Yet, their employment rate remains substantially lower compared with the general population without disabilities. Scaling up the employment outcomes of this population requires improving the effectiveness and efficiency of employment support systems. To this end, this article recommends supporting employment providers rethink how they use their management information systems (MIS): from primary tools that automate billing and compliance, to tools that track metrics for continuous quality improvement. As federal and state funding policies are the main factors shaping how MIS are currently used, this article recommends that federal and state policy guidelines be issued that enable employment providers to leverage their MIS to improve effectiveness and efficiency, and thus scale up employment outcomes of job seekers.

Prevalence and incidence of physical health conditions in people with intellectual disability - a systematic review

OBJECTIVE

To synthesize evidence on the prevalence and incidence of physical health conditions in people with intellectual disability (ID).

METHODS

We searched Medline, PsycInfo, and Embase for eligible studies and extracted the prevalence, incidence, and risk of physical health conditions in people with ID.

RESULTS

Of 131 eligible studies, we synthesized results from 77 moderate- to high-quality studies, which was mainly limited to high-income countries. The highest prevalence estimates were observed for epilepsy, ear and eye disorders, cerebral palsy, obesity, osteoporosis, congenital heart defects, and thyroid disorders. Some conditions were more common in people with a genetic syndrome. Compared with the general population, many health conditions occur more frequently among people with ID, including asthma and diabetes, while some conditions such as non-congenital circulatory diseases and solid cancers occur at the same or lower rate. The latter associations may reflect under-detection.

CONCLUSIONS

People with ID have a health profile more complex than previously known. There is a pressing need for targeted, evidence-informed population health initiatives including preventative programs for this population.

Using linked administrative data to determine the prevalence of intellectual disability in adult prison in New South Wales, Australia

BACKGROUND

Studies of the representation of people with intellectual disability (ID) in custody report widely inconsistent findings that reflect variation in how ID is defined and the methods employed for identification. Using linked administrative data may be of utility in studies of the representation of people with ID in custody. However, this approach requires an understanding of the purpose of and factors influencing identification in disparate administrative datasets.

METHODS

This study uses linked administrative data encompassing disability, health and corrections data for the year 2014 to estimate the prevalence of ID in adult custody and explore how ID representation within administrative data impacts prevalence estimates and what patterns of identification reveal about support service access for this group.

RESULTS

This study finds that 4.3% of the New South Wales adult custody population had an identified ID. Prisoners with ID were younger, more likely to have had a previous custodial episode and more likely to be Indigenous than the general prison population. Identification of ID across linked administrative datasets is uneven, which, if used in isolation, would result in variation in prevalence estimates according to source data.

CONCLUSIONS

The utilisation of linkage data from a broad range of health and support services including custody offers a comprehensive identification methodology. Inconsistency in the identification of ID across datasets indicates a potential disjuncture between prisoners with ID and support services, which may have relevance for efforts to reduce reincarceration of those in this population.

Survival of children and adolescents with intellectual disability following gastrostomy insertion

BACKGROUND

Positive health outcomes have been observed following gastrostomy insertion in children with intellectual disability, which is being increasingly used at younger ages to improve nutritional intake. This study investigated the effect of gastrostomy insertion on survival of children with severe intellectual disability.

METHODS

We used linked disability and health data of children and adolescents who were born in Western Australia between 1983 and 2009 to compare survival of individuals with severe intellectual disability by exposure to gastrostomy status. For those born in 2000-2009, we employed propensity score matching to adjust for confounding by indication. Effect of gastrostomy insertion on survival was compared by pertinent health and sociodemographic risk factors.

RESULTS

Compared with children born in the 1980s-1990s, probability of survival following first gastrostomy insertion for those born in 2000-2009 was higher (2 years: 94% vs. 83%). Mortality risk was higher in cases than that in their matched controls (hazard ratio 2.9, 95% confidence interval 1.1, 7.3). The relative risk of mortality (gastrostomy vs. non-gastrostomy) may have differed by sex, birthweight and time at first gastrostomy insertion. Respiratory conditions were a common immediate or underlying cause of death among all children, particularly among those undergoing gastrostomy insertion.

CONCLUSIONS

Whilst gastrostomy insertion was associated with lower survival rates than children without gastrostomy, survival improved with time, and gastrostomy afforded some protection for the more vulnerable groups, and earlier use appears beneficial to survival. Specific clinical data that may be used to prioritise the need for gastrostomy insertion may be responsible for the survival differences observed.

The prevalence and health status of people with developmental disabilities in provincial prisons in Ontario, Canada: A retrospective cohort study

BACKGROUND

Data on the prevalence of developmental disabilities in people who experience imprisonment and on their characteristics are lacking.

METHODS

The present authors identified adults with developmental disabilities who were released from Ontario provincial prisons in 2010 and a general population comparator group using administrative data. The present authors examined demographic characteristics, morbidity and healthcare use.

RESULTS

The prevalence of developmental disabilities was 2.2% in the prison group (N = 52,302) and 0.7% in the general population (N = 10,466,847). The prevalence of psychotic illness, substance-related disorder and self-harm was higher among people in the prison group with developmental disabilities. People with developmental disabilities were more likely to have emergency department visits and hospitalizations in prison and in the year after release.

CONCLUSIONS

People with developmental disabilities are overrepresented in provincial prisons and have a high burden of disease. Strategies are indicated to prevent incarceration and to improve health.

Assessing the quality, efficiency and usefulness of the Western Australian population-based Intellectual Disability Exploring Answers (IDEA) surveillance system: a surveillance system evaluation

OBJECTIVES

Our overall aim was to evaluate the Western Australian Intellectual Disability Exploring Answers (IDEA) surveillance system. The primary objective was to evaluate the attributes of the system. The secondary objective was to provide recommendations to data custodians and stakeholders to strengthen the system.

METHOD

The IDEA system was evaluated using process observation, interviews and secondary data analysis of system attributes: usefulness, simplicity, data quality, acceptability, representativeness, timeliness and stability. 2001 US Centers for Disease Control and Prevention guidelines were used.

RESULTS

We found that the IDEA system was useful, simple, flexible, acceptable, representative, timely and stable. We compared individuals from the IDEA system (n=10 593) with those with cerebral palsy and intellectual disability (ID) (n=582) from another surveillance system. Of the 582 with cerebral palsy and ID, 501 (86.1%) were in the IDEA system and 81 (13.9%) were not. In total, 0.7% of cases (81/10674) with ID were not identified in the IDEA system. There were little differences in cases that were not identified in the IDEA system between Indigenous status, sex and place of residence.

CONCLUSIONS

The strengths of the IDEA system include having a high data quality resource contributing to national and international data on ID, strong government support and a dedicated management team. Output from studies linking to IDEA data have had major contributions to the international literature about ID. However, limited resources have prevented it from realising its full potential in relation to translational activities. The IDEA system is a valuable resource to address the needs of people living with ID.

A Call for Better Data on Prevalence and Health Surveillance of People With Intellectual and Developmental Disabilities

The U.S. approach to the health of people with intellectual and developmental disabilities (IDD) is fraught with paradox. The health of this population has been of longstanding concern, yet we understand their health less well than many other groups. The U.S. spends much more per person on the well-being of people with IDD compared to the general population, yet the outcomes of those expenditures are disappointing and include significant preventable health disparities. Even as expectations for people with IDD have changed to include better health and greater participation in their communities, eligibility for services that support these outcomes is rooted in expectations of dependence and poverty. This article is a call for better data that considers a series of questions to provide context for understanding the need and directions for better health surveillance of people with IDD.