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One in 20 Ontario youth diagnosed with ADHD, and many prescribed an antipsychotic despite no other mental health diagnosis: study


One in 20 Ontario youth have been diagnosed with attention deficit hyperactivity disorder (ADHD) and many are prescribed antipsychotic drugs despite having no other identified mental health diagnosis, according to a new study from the Institute for Clinical Evaluative Sciences (ICES).

“We don’t know why these children and youth with ADHD are on antipsychotics, but there is a risk associated with early antipsychotic exposure, so we need to know more about why they are being used so that the benefits can be weighed against the risks,” says Dr. Paul Kurdyak, senior author, scientist at ICES and the Centre for Addiction and Mental Health (CAMH)’s Institute for Mental Health Policy Research.

In the study, published today in the Canadian Journal of Psychiatry, the researchers looked at youths aged 1 to 24 throughout Ontario in 2011, and examined data relating to ADHD and other diagnoses, along with medications and health service use, as well as demographic characteristics. The researchers found 5.4 per cent of the children and youth in the study had a diagnosis of ADHD (7.9 per cent males, 2.7 per cent females) and the majority of them (70 per cent) received prescriptions for ADHD medication.

Nearly 12 per cent of the youth with ADHD received an antipsychotic prescription, but very few of these youth had other psychiatric diagnoses that would be treated with antipsychotics. Antipsychotic drugs – such as Risperdal, Zyprexa and Seroquel – were developed to treat schizophrenia. In addition to schizophrenia, there is evidence these powerful medications treat certain behaviours in ADHD, although not the core symptoms of hyperactivity and inattention. Moreover, these drugs are associated with risks such as significant weight gain and the development of diabetes. One in four of the youth who received an antipsychotic had no other record of a mental health diagnosis.

“Our findings show that youth who have a diagnosis of ADHD and receive an antipsychotic are more complex. They see more care providers, they have more emergency department and mental health-related physician visits, more comorbidities and receive more prescriptions,” says Dr. Tanya Hauck, author and psychiatry resident at the University of Toronto.

The study also found that one in five youth with ADHD received an antidepressant prescription.

“The high number of youth with ADHD who do receive an antidepressant illustrates how ADHD is often not the only condition these youth experience. One in five youth with ADHD received a prescription for an antidepressant versus one in 20 without ADHD,” adds Hauck.

The research found increasing age, psychiatric consultation and diagnoses of both anxiety and depression were factors for predicting antidepressant prescriptions but only psychiatric consultation predicted antipsychotic prescriptions.

The researchers add that a limitation of the study is that while it looked at prescriptions that were written, it couldn't show whether these prescriptions were filled or the duration these drugs were prescribed.

“ADHD treatment in primary care: demographic factors, medication trends, and treatment predictors,” was published today in the Canadian Journal of Psychiatry.

Author block: Hauck TS, Lau C, Wing LLF, Kurdyak P, Tu K.

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


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


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