International guide to prescribing psychotropic medication for the management of problem behaviours in adults with intellectual disabilities

Aggressive challenging behaviour is frequently reported in adults with intellectual disability and it is often treated with antipsychotic drugs. However, no adequate evidence base for this practice exists. We compared flexible doses of haloperidol (a typical, first-generation antipsychotic drug), risperidone (an atypical, second-generation antipsychotic), and placebo, in the treatment of this behaviour. 86 non-psychotic patients presenting with aggressive challenging behaviour from ten centres in England and Wales, and one in Queensland, Australia, were randomly assigned to haloperidol (n=28), risperidone (n=29), or placebo (n=29). Clinical assessments of aggression, aberrant behaviour, quality of life, adverse drug effects, and carer uplift (positive feelings about the care of the disabled person) and burden, together with total costs, were recorded at 4, 12, and 26 weeks. The primary outcome was change in aggression after 4 weeks' treatment, which was recorded with the modified overt aggression scale (MOAS). Analysis was by intention to treat. This study is registered as ISRCTN 11736448. 80 patients had adherence of 80% or more to prescribed drug. Aggression decreased substantially with all three treatments by 4 weeks, with the placebo group showing the greatest change (median decrease in MOAS score after 4 weeks=9 [95% CI 5-14] for placebo, 79% from baseline; 7 [4-14] for risperidone, 58% from baseline; 6.5 [5-14] for haloperidol, 65% from baseline; p=0.06). Furthermore, although no important differences between the treatments were recorded, including adverse effects, patients given placebo showed no evidence at any time points of worse response than did patients assigned to either of the antipsychotic drugs. Antipsychotic drugs should no longer be regarded as an acceptable routine treatment for aggressive challenging behaviour in people with intellectual disability.

Variations in reported prevalence of challenging behaviour indicate the need for further epidemiological research to support accurate planning of future service provision.

Aggressive behaviours can be disabling for adults with intellectual disabilities (ID), with negative consequences for the adult, their family and paid carers. It is surprising how little research has been conducted into the epidemiology of these needs, given the impact they can have. This study investigates point prevalence, 2-year incidence and 2-year remission rates for aggressive behaviour (physically aggressive, destructive and verbally aggressive), and it investigates which factors are independently associated with aggressive behaviour. All adults with ID - within a geographically defined area of Scotland, UK - were recruited to a longitudinal cohort. At baseline, assessments were undertaken of demography, lifestyle, supports, development, problem behaviours, disabilities and physical and mental health. These were repeated for a 2-year period. At baseline, the participation rate was 1023 (65.5%). After 2 years, the cohort retention was 651 adults. The point prevalence of Diagnostic Criteria for Psychiatric Disorders for Use with Adults with Learning Disabilities/Mental Retardation (DC-LD) aggressive behaviour was 9.8% (95% confidence interval = 8.0-11.8%), 2-year incidence was 1.8%, and 2-year remission rate from all types of aggressive behaviour meeting DC-LD criteria was 27.7%. The factors independently associated with aggressive behaviours were lower ability, female gender, not living with a family carer, not having Down syndrome, having attention-deficit hyperactivity disorder and having urinary incontinence. Incidence of aggressive behaviour meeting DC-LD criteria in adult life is similar to that for each of psychotic, anxiety and organic disorders. Aggressive behaviour is common among adults with ID, but contrary to previous suggestions, more than a quarter remit within the short to medium term. This is important knowledge for professionals as well as the person and her/his family and paid carers. There is much yet to learn about the mechanisms underpinning aetiology and maintenance of aggressive behaviour in this population, and exploratory epidemiological investigations such as this have a role to play in progressing research towards further hypothesis testing and trials to influence clinical practice, service development and policy.