Many people with intellectual disabilities are inappropriately prescribed antipsychotic drugs, according to a new U.K. study by researchers at University College London (UCL).
Intellectual disability is defined as a lifelong condition that begins before the age of 18 and is characterized by limitations in intellectual functioning (generally indicated by an IQ under 70) and difficulties with one or more life skills. It affects approximately one percent of the population.
“The number of people with intellectual disabilities who have been prescribed antipsychotics is greatly disproportionate to the number diagnosed with severe mental illness for which they are indicated,” said study author Dr. Rory Sheehan of UCL Psychiatry.
“People who show problem behaviors, along with older people with intellectual disability or those with co-existing autism or dementia, are significantly more likely to be given an antipsychotic drug, despite this being against clinical guidelines and risking possible harm.”
The researchers studied anonymous medical records of 33,016 UK adults with intellectual disabilities between 1999 and 2013. They found that more than one-fourth of these patients had been prescribed antipsychotic drugs, of whom 71 percent had no record of severe mental illness.
Antipsychotic drugs are designed to treat severe mental illnesses such as schizophrenia. There is very little evidence that they help treat behavioral issues not due to mental illness in people with intellectual disability.
Despite this, however, the findings showed that antipsychotics were commonly prescribed to people with behavior problems with no history of severe mental illness. Behavior problems that might be seen in people with intellectual disability include aggression, self-injury, or destruction to property.
People with intellectual disability who also had autism or dementia were also more likely to be prescribed an antipsychotic drug, as were older people.
Other classes of drugs used to treat mental illness were also commonly prescribed to people with intellectual disability.
Drugs used to treat anxiety were the most frequently prescribed, followed by antidepressants. Both were prescribed at notably higher rates than mental disorders were recorded. This suggests that these drugs might also be prescribed inappropriately in some cases.
The researchers paid particular attention to investigating the use of antipsychotics due to their risk of serious side-effects, which include sedation, weight gain, metabolic changes that can ultimately lead to diabetes, and movement problems such as restlessness, stiffness, and shakiness.
“Side-effects can be managed, but the risks and benefits must be carefully considered before prescribing antipsychotics to people without severe mental illness,” said Sheehan.
“Research evidence does not support using antipsychotics to manage behavior problems in people with intellectual disabilities. Many people with intellectual disability and behavior disturbance have complex needs and other interventions, such as looking at the support people receive and their communication needs, should be prioritized. Antipsychotics, or indeed any medications, should not be prescribed lightly and are no substitute for comprehensive care.”
The findings are published in The BMJ.