Effects of controlled discontinuation of long-term used antipsychotics for behavioural symptoms in individuals with intellectual disability.

BACKGROUND

Antipsychotics are frequently and often long-term used for challenging behaviour in persons with intellectual disability (ID), but the evidence base for this is meagre. As these agents may cause harmful side effects, discontinuation should be considered. Previous studies regarding discontinuation of long-term used antipsychotics mostly were uncontrolled and involved small numbers. The primary objective was to investigate the effects of controlled discontinuation of antipsychotics prescribed for challenging behaviour. Secondary objectives were to compare the results of two discontinuation time schedules, to compare groups of participants who had and had not achieved complete discontinuation, and to identify patient and medication characteristics that might predict the outcomes. Our hypothesis was that discontinuation of antipsychotics used for behavioural symptoms would not lead to worsening in behaviour.

METHODS

This was a multi-centre parallel-group study comparing two discontinuation schedules of 14 and 28 weeks. Allocation to the two discontinuation schedules took place in a 1:1 ratio. Antipsychotics were tapered off every 2 or 4 weeks with approximately 12.5% of the initial dosage. Follow-up was 12 weeks after the scheduled complete discontinuation, that is, 26 or 40 weeks after the first dose reduction, respectively. Discontinuation was stopped in case of significant behavioural worsening. Participants were 98 residents with ID of three care providing organisations in the Netherlands, aged 15-66 year, who had used for more than 1 year one or more of the six most frequently prescribed antipsychotics for challenging behaviour. Main outcome measure was the total score of the Aberrant Behaviour Checklist (ABC); also ABC sub-scales were used.

RESULTS

Of 98 participants, 43 achieved complete discontinuation; at follow-up 7 had resumed use of antipsychotics. Mean ABC ratings improved significantly for those who achieved complete discontinuation (directly after discontinuation, P < 0.01 and at follow-up, P = 0.03), and at follow-up (P = 0.03) for those who had not achieved complete discontinuation. Similar results were found with respect to most ABC sub-scales, including the 'irritability' sub-scale. There were no significant differences in improvement of ABC ratings between both discontinuation schedules. Higher ratings of extrapyramidal and autonomic symptoms at baseline were associated with less improvement of behavioural symptoms after discontinuation; higher baseline ABC rating predicted higher odds of incomplete discontinuation.

CONCLUSIONS

Discontinuation of antipsychotics prescribed for challenging behaviour in patients with ID is associated with improved behavioural functioning. There is no need to taper off in a time frame longer than 14 weeks.