Neuroleptics in the Treatment of Aggressive Challenging Behavior for People with Intellectual Disabilities: A Randomized Controlled Trial (NACHBID)

Aim: To investigate the value of giving antipsychotic drugs to adults with intellectual disability when they show challenging behavior (manifest mainly by anger and aggression).

Conclusions and results: We tested a specific research question involving representatives from both groups of antipsychotic drugs: Do typical and atypical antipsychotic drugs (haloperidol and risperidone) given in flexible dosage reduce aggression in challenging behavior in learning disability to a greater extent than placebo medication in both the short term (4 weeks) and medium term (12-26 weeks)?

Eighty-six patients, predominantly male (62%) (1 with borderline intellectual disability, 30 with mild, 41 with moderate, and 14 with severe intellectual disability) with similar distribution by randomized group, were randomized from 10 centers in England and Wales, and one in Queensland, Australia between November 6, 2002 and August 24, 2006. Twenty-two clinicians recruited patients, with three recruiting 40 patients between them. Since this was a much lower rate of recruitment than planned, we extended the recruitment period from 24 to 45 months. There were no dropouts from assessment in the first 4 weeks, 29% at 12 weeks, and 43% at 26 weeks (with all patients and clinicians having the option to discontinue the study after 12 weeks). The mean daily dosage for risperidone was 1.07mg rising to 1.78mg, and haloperidol 2.54 mg rising to 2.94mg. Aggression declined dramatically with all three treatments after 1 week, but this was maintained to a greater extent with placebo. After 4 weeks placebo showed the greatest reduction (79%, vs 57% for combined drugs) (P=0.06). None of the other secondary measures showed any drug-placebo differences.

Recommendations: This trial provides no evidence that either risperidone or haloperidol given in conventionally low doses offer any advantages over placebo in short- and medium-term treatment of aggressive, challenging behavior in intellectual disability, and over 4 weeks placebo was somewhat more effective in reducing aggression. Placebo treatment is also cheaper than the other two treatments over a 6-month period in terms of total costs. It is concluded that placebo is the most cost-effective of the three treatments for aggressive challenging behavior.

Methods: See Executive Summary link at www.ncchta.org/project/1322.asp.

Further research/reviews required: The current use of antipsychotic drugs in treating aggressive challenging behavior in intellectual disability requires review. The findings suggest that much of this prescribing may be unnecessary, and other forms of treatment, probably of a psychological nature, should be tested in randomized studies.

Written by: Professor Peter Tyrer, Imperial College London, NETSCC, United Kingdom