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Antipsychotics common for adults with intellectual and developmental disabilities


Six-year Canadian study shows prescriptions often occur in adults with no psychiatric diagnosis

Antipsychotic medication is frequently being prescribed to individuals with intellectual and developmental disabilities (IDD), often without a psychiatric diagnosis, a new study conducted by the Institute for Clinical Evaluative Sciences (ICES) and the Centre for Addiction and Mental Health (CAMH) has found.

IDD includes diagnoses such as Down syndrome, fetal alcohol syndrome and autism.

The study published today in The Canadian Journal of Psychiatry has made significant strides in filling the gap in research about prescribing practices of antipsychotic medication to adults with IDD. The six-year population-based study examined the healthcare data of 51,881 adults with IDD who were less than 65 years of age. Similar research has been conducted in other jurisdictions; however, this study is the first population-based study to investigate the use of antipsychotic medication in adults with IDD in Canada.

“The results of our study make us question how often antipsychotics are being used as a tool to manage behavioural issues. We need to understand more about why these medications are prescribed to those without psychiatric disorders, what else has been tried prior to medication, and how well these medications are being monitored,” says lead author Yona Lunsky, adjunct scientist at ICES, a clinician-scientist at CAMH and director of the Healthcare Access Research and Developmental Disabilities (H-CARDD) research program.

Antipsychotics can be prescribed to adults with IDD as a method of managing behavioural challenges, sometimes without a comprehensive assessment of the underlying contributors to such behaviours, despite the evidence supporting such use being inconclusive. According to guidelines, antipsychotics should not be used as a first line treatment for behaviour challenges.

“This study shows that antipsychotic use in adults with IDD is common. We need to pay more attention to how antipsychotics are prescribed and monitored to ensure appropriate prescribing for this vulnerable population,” says Tara Gomes, co-author on the study, a scientist at ICES, a principal investigator of Ontario Drug Policy Research Network (ODPRN) and a scientist at and the Li Ka Shing Knowledge Institute of St. Michael’s Hospital.

The researchers add that antipsychotic prescribing is particularly problematic for this population due to the potential for adverse effects such as the increased risk for metabolic complications. In this study, one in six adults had diabetes and one in five had hypertension. Furthermore, adults with IDD may have difficulties in providing informed medical consent and reporting unfavourable side effects should they arise.

The six-year study found:

  • 39 per cent of Ontario adults with IDD were dispensed antipsychotic medication (20,316 individuals)
  • 29 per cent of the antipsychotic users did not have a documented psychiatric diagnosis

This study also analyzed a sub-cohort of adults with IDD living in Ontario group homes and found:

  • 56 per cent (4,073) of individuals residing in group homes were prescribed an antipsychotic
  • Of the antipsychotic users in a group home setting, 43 per cent did not have a documented psychiatric diagnosis

These findings are in line with a major UK study also demonstrating high antipsychotics use, sometimes in the absence of a psychiatric diagnosis. The “STOMP" movement in the UK is a shared commitment by the Colleges of Psychiatrists, Pharmacists, General Practitioners, Nurses, Psychologists and the National Health Service to curb the over-prescription of psychotropic medications to persons with IDD.

“Ideally this research, by providing a glimpse into antipsychotic prescribing practices among adults with IDD in Ontario will trigger a national conversation about medication policies, practices and training here,” adds Lunsky.

“Antipsychotic use with and without comorbid psychiatric diagnosis among adults with intellectual and developmental disabilities,” was published today in the Canadian Journal of Psychiatry.

Author block: Lunsky Y, Khuu W, Tadrous M, Vigod S, Cobigo V, Gomes T.

The Institute for Clinical Evaluative Sciences (ICES) is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy. For the latest ICES news, follow us on Twitter: @ICESOntario

The Centre for Addiction and Mental Health (CAMH) is Canada's largest mental health and addiction teaching hospital and a world leading research centre in this field. CAMH combines clinical care, research, education, policy development and health promotion to help transform the lives of people affected by mental illness and addiction. CAMH is fully affiliated with the University of Toronto, and is a Pan American Health Organization/World Health Organization Collaborating Centre. For more information, please visit camh.ca or follow @CAMHnews on Twitter.


Deborah Creatura
Media Advisor, ICES
[email protected]
(o) 416-480-4780 or (c) 647-406-5996

Sean O’Malley
Media Relations, CAMH
(416) 595-6015 / [email protected]

Read the Journal Article