Antipsychotic use with and without comorbid psychiatric diagnosis among adults with intellectual and developmental disabilities

Objective — Antipsychotic use is controversial in the management of adults with intellectual and developmental disabilities (IDD) because of inconclusive evidence for efficacy in the absence of a comorbid psychiatric condition, and substantial concerns about adverse effects. We aimed to characterize antipsychotic use among Ontario adults with IDD and compare profiles of those with and without a documented psychiatric diagnosis.

Method — This population-based study included 51,881 adults with IDD under 65 y as of April 2010 receiving provincial drug benefits in Ontario who were followed until March 2016 to identify those dispensed at least one antipsychotic medication. Profiles of those with and without a psychiatric diagnosis were compared.

Results — Overall, 39.2% of adults (n = 20,316) were dispensed an antipsychotic medication, which increased to 56.4% in a subcohort residing in group homes. Almost one-third (28.91%) of people prescribed an antipsychotic medication did not have a documented psychiatric diagnosis. Those without a psychiatric diagnosis differed considerably from those with a diagnosis. In particular, those without a psychiatric diagnosis were older, less likely to have used antidepressants or benzodiazepines in the year before, and less likely to have used ambulatory and acute care.

Conclusions — Antipsychotic use in IDD is common, and occurs frequently without a psychiatric diagnosis. Attention toward how antipsychotics are prescribed and monitored for people with IDD in Canada is warranted to ensure appropriate prescribing.