Large numbers of people with intellectual disabilities are being inappropriately prescribed antipsychotic drugs, finds a new UCL study.
Intellectual disability is a lifelong condition that begins before the age of 18 and is characterised by limitations in intellectual functioning (generally indicated by an IQ under 70) and difficulties with one or more life skills. Around 1% of the population has an intellectual disability.
The new study, published in The BMJ, looked at anonymised GP records of 33,016 UK adults with intellectual disabilities between 1999 and 2013. It found that over one-quarter had been prescribed antipsychotic drugs, of whom 71% 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 to address behavioural problems not due to mental illness in people with intellectual disability. Despite this, the study found that antipsychotics were often prescribed to people with behaviour problems who had no history of severe mental illness. Behaviour problems that might be seen in people with intellectual disability include aggression, self-injury, destruction to property and other behaviours outside social norms.
People with intellectual disability who also had autism or dementia were also more likely to receive an antipsychotic drug, as were older people.
“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.” explains study author Dr Rory Sheehan (UCL Psychiatry). “People who show problem behaviours, 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.”
However, the study also found that the rate of prescribing of antipsychotic drugs to people with intellectual disability had fallen gradually but consistently over the past 15 years, indicating that alternative therapies are being utilised and GPs are changing their practice.
Other classes of drugs used to treat mental illness were also prescribed to people with intellectual disability in large numbers. Drugs used to treat anxiety were the most frequently prescribed, followed by the antidepressants (used to treat depression). Like the antipsychotic group, both of these types of drug were given at substantially 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.
Side-effects of antipsychotic drugs 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,” says Dr Sheehan. “Research evidence does not support using antipsychotics to manage behaviour problems in people with intellectual disabilities. Many people with intellectual disability and behaviour disturbance have complex needs and other interventions, such as looking at the support people receive and their communication needs, should be prioritised. Antipsychotics, or indeed any medications, should not be prescribed lightly and are no substitute for comprehensive care.”
Source: Harry Dayantis – UCL
Image Source: The image is adapted from the UCL pres release and is credited to Housed. The image is licensed CC BY-SA 3.0
Original Research: Full open access research for “Mental illness, challenging behaviour, and psychotropic drug prescribing in people with intellectual disability: UK population based cohort study” by Sheehan Rory, Hassiotis Angela, Walters Kate, Osborn David, Strydom André, and Horsfall Laura in BMJ. Published online September 1 2015 doi:10.1136/bmj.h4326
Mental illness, challenging behaviour, and psychotropic drug prescribing in people with intellectual disability: UK population based cohort study
Objectives To describe the incidence of recorded mental illness and challenging behaviour in people with intellectual disability in UK primary care and to explore the prescription of psychotropic drugs in this group.
Design Cohort study.
Setting 571 general practices contributing data to The Health Improvement Network clinical database.
Participants 33 016 adults (58% male) with intellectual disability who contributed 211 793 person years’ data.
Main outcome measures Existing and new records of mental illness, challenging behaviour, and psychotropic drug prescription.
Results 21% (7065) of the cohort had a record of mental illness at study entry, 25% (8300) had a record of challenging behaviour, and 49% (16 242) had a record of prescription of psychotropic drugs. During follow-up, the rate of new cases of mental illness in people without a history at cohort entry was 262 (95% confidence interval 254 to 271) per 10 000 person years and the rate of challenging behaviour was 239 (231 to 247) per 10 000 person years. The rate of new psychotropic drug prescription in those without a previous history of psychotropic drug treatment was 518 (503 to 533) per 10 000 person years. Rates of new recording of severe mental illness declined by 5% (95% confidence interval 3% to 7%) per year (P<0.001), and new prescriptions of antipsychotics declined by 4% (3% to 5%) per year P<0.001) between 1999 and 2013. New prescriptions of mood stabilisers also decreased significantly. The rate of new antipsychotic prescribing was significantly higher in people with challenging behaviour (incidence rate ratio 2.08, 95% confidence interval 1.90 to 2.27; P<0.001), autism (1.79, 1.56 to 2.04; P<0.001), and dementia (1.42, 1.12 to 1.81; P<0.003) and in those of older age, after control for other sociodemographic factors and comorbidity.
Conclusions The proportion of people with intellectual disability who have been treated with psychotropic drugs far exceeds the proportion with recorded mental illness. Antipsychotics are often prescribed to people without recorded severe mental illness but who have a record of challenging behaviour. The findings suggest that changes are needed in the prescribing of psychotropics for people with intellectual disability. More evidence is needed of the efficacy and safety of psychotropic drugs in this group, particularly when they are used for challenging behaviour.
“Mental illness, challenging behaviour, and psychotropic drug prescribing in people with intellectual disability: UK population based cohort study” by Sheehan Rory, Hassiotis Angela, Walters Kate, Osborn David, Strydom André, and Horsfall Laura in BMJ. Published online September 1 2015 doi:10.1136/bmj.h4326