A pragmatic cluster randomised controlled trial of a complex ward-based intervention on antipsychotic polypharmacy prescribing in adult psychiatric inpatient wards The DEBIT Team: Dr Andy Thompson, Maddi Barley, Sarah Sullivan, Simon Strange, Professor Laurence Moore, Dr Attila Sipos, Professor Glynn Harrison: Academic Unit of Psychiatry, Cotham House, Cotham Hill, Bristol, BS6 6JL Introduction Clinical practice guidelines, such as those developed by the UK National Institute for Clinical Excellence (NICE) on the management of patients with schizophrenia (NICE, 2002), are designed to address variation in clinical practice. These Guidelines advise against the use of more than one antipsychotic except in a small number of circumstances but U.K. surveys suggest this is still a widespread practice (Harrington et al 2002). Simply the dissemination of guidelines does not appear to change practice. Systematic reviews have demonstrated that interventions such as educational outreach visits (academic detailing), reminder systems and educational workshops can be effective at changing clinicians’ behaviour, especially when combined in ‘multifaceted’ interventions (NHS Centre for Reviews and Dissemination, 1999; Chilvers, et al, 2002). Conclusions A complex intervention aimed at ward doctors and nurses significantly reduced the odds of patients being prescribed antipsychotic polypharmacy, compared with professionals in the control units who received guidelines alone. The approach of addressing specific barriers to change with a multi-faceted intervention and the utilisation of existing clinical governance strategies in this study suggests that the effect of this intervention could be generalisable to other trusts and the implementation of good prescribing practice in other areas of care. Further work is needed to elicit the factors in this complex intervention that were active in changing prescribing behaviour, the absolute pattern of prescribing changes and whether the effect is sustained. Methods Design The flow diagram Figure 1 shows the recruitment, randomisation and allocation process. Randomisation was stratified by unit size and trust. Participants were all qualified nurses and doctors working in the units, identified prior to the trial The trial ran from the beginning of February to the end of July 2004 in order to coincide with the 6 monthly junior doctor rotation (to limit the degree of contamination caused by these doctors moving between units or trusts). Each trust adopted the trial as part of their clinical governance strategy. Outcome measures Primary outcome measure – This was the rate of antipsychotic prescribing for each unit, as a measure of the change in behaviour. We undertook a one-day cross-sectional survey at 2 time points, pre intervention (February 2004) and post intervention (July 2004). Drug and patient demographic data were collected by the four Trusts (for reasons of patient confidentiality), anonymised, and returned to the research team for analysis. Secondary outcome measure – This was a questionnaire sent to all doctors and nurses pre and post intervention looking at beliefs towards aspects of antipsychotic polypharmacy addressed in the educational workbook (see intervention), as a measure of the change in beliefs. The results are not presented in this poster. Analysis The primary outcome was analysed using a unit-level weighted (using the baseline ICC) regression analysis adjusting for baseline score and the stratifying variables (size of unit and trust). There was considerable variation in the amount of change between intervention units with all but three units showing a reduction in polypharmacy rates (ranging from a reduction of 26% to and increase of 7%). There was similar variation in the control units.Table 1 shows the predefined regression model both unadjusted and adjusted for potential confounders, Table 2 show a post hoc analysis adjusting for the effect of stand-alone high dependency or intensive care units. Both models show a significant reduction in polypharmacy prescribing in the intervention group with adjusting for stand alone units increasing this effect. This suggests that the effect of the intervention may have been greater had the number of stand-alone units been equally distributed between the control and intervention arms. Results Figure 1 shows the flow of participants and patients through the study. A comparison of baseline characteristics of the 19 units showed that they were reasonably similar between control and intervention arms, except that there were more specialist beds in the intervention units. Table 1 shows the polypharmacy rates for the control and intervention units pre and post intervention. There was a higher proportion of polypharmacy at baseline in the intervention units compared to the control units. The overall percentage of polypharmacy decreased 7.4% in the intervention arm and increased 7% in the control arm References Chilvers R., Harrison G., Sipos A., and Barley, M. (2002). Evidence into practice: Application of psychological models of change in evidence-based implementation. British Journal of Psychiatry, 181, Harrington, M., Lelliott, P., Paton, C., Okocha, C., Duffett, R. & Sensky, T. (2002) The results of a multi-centre audit of the prescribing of antipsychotic drugs for in-patients in the UK. Psychiatric Bulletin, 26 (11), National Institute for Clinical Excellence (2002). Guidance on the use of newer (atypical) antipsychotic drugs for the treatment of schizophrenia. London: National Institute for Clinical Excellence. NHS Centre for Reviews and Dissemination, (1999). Getting evidence into practice. Effective Healthcare Bulletin, 5 (1), 1-6. Intervention The intervention comprised of three parts: Educational outreach visit – a structured personal visit lasting minutes by a psychiatric pharmacist trained in social marketing techniques. The visit included a review of the current evidence on antipsychotic polypharmacy and some predefined suggestions on how to reduce current levels of polypharmacy and an agreement to review current medication charts. Consultants received a follow up visit or phone call to review progress on agreed targets and discuss their views on the educational workbook (see below). Educational workbook - This workbook was designed to be an educational resource for doctors and nurses, and adapted a cognitive behavioural framework to the issue of polypharmacy. It included a literature review of the current issues, alternative strategies to polypharmacy, and suggestions for reflection on practice and ideas for change. This was informed by our previous qualitative work on antipsychotic prescribing with nurses and consultants. A brief follow up booklet was sent to all participants two months later Medication chart prompt system - This system was implemented by the ward pharmacists. Medication charts were reviewed on a regular basis (weekly) and removable stickers were applied to the charts of patients who were being prescribed more than one antipsychotic (either on a regular basis, as required or once only). The control units received only a guideline on antipsychotic polypharmacy Table 2: Unadjusted and adjusted (for cluster size, trust to which the cluster belongs and baseline proportion of antipsychotic polypharmacy) weighted regression analysis of the difference between intervention and control groups in the proportion of patients prescribed antipsychotic polypharmacy. Table 3: Unadjusted and adjusted (for cluster size, trust to which the cluster belongs and baseline proportion of antipsychotic polypharmacy and stand-alone HDU/PICU Unit) weighted regression analysis of the difference between intervention and control groups in the proportion of patients prescribed antipsychotic polypharmacy. Table 1: Percentages of prescribed antipsychotic polypharmacy in control and intervention units pre and post intervention (with associated 95% confidence intervals accounting for clustering). Aim To evaluate a complex intervention strategy aimed at reducing antipsychotic polypharmacy prescribing on psychiatric inpatient wards using a cluster randomised controlled trial. G.P. Dr Hibble with his year’s worth of clinical guidelines – but do they alone change practice?