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

Abstract

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 Scotlands 2011 Census to 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/ 7,247 (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). SMR for children/young people with, versus those without, intellectual disabilities were 10.7 for all causes (95% confidence interval (CI)=9.47-12.1), 5.17 for avoidable death (CI=4.19-6.37), 2.3 for preventable death (1.6-3.2), and 16.1 for treatable death (CI=12.5-20.8). SMRs were highest for children (27.4, CI=20.6-36.3) aged 5-9 years, and lowest for young people (6.6, CI=5.1-8.6) 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 ICD-10 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 health-care to reduce treatable mortality should be a priority for children/young people with intellectual disabilities. Examples include improved epilepsy management and risk assessments, and co-ordinated multi-disciplinary actions to reduce aspiration/reflux/choking and respiratory infection. This is necessary across all neighbourhoods.