Application of the structured history taking of medication use tool to optimise prescribing for older patients and reduce adverse events

Background Older patients, due to polypharmacy, co-morbidities and often multiple prescribing doctors are particularly susceptible to medication history errors, leading to adverse drug events, patient harm and increased costs. Medication reconciliation at the point of admission to hospital can reduce medication discrepancies and adverse events. The Structured HIstory taking of Medication use (SHiM) tool was developed to provide a structure to the medication reconciliation process. There has been very little research with regards to SHiM, it’s application to older patients and it’s potential to reduce adverse events. Objective To determine whether application of SHiM could optimise older patients’ prescriptions on admission to hospital, and in-turn reduce adverse events, compared to standard care. Setting A sub-study of a large clinical trial involving hospital inpatients over the age of 65 in five hospitals across Europe. Method A modified version of SHiM was used to obtain accurate drug histories for patients after the attending physician had obtained a medication list via standard methods. Discrepancies between the two lists were recorded and classified, and the clinical relevance of the discrepancies was determined. Whether discrepancies in patients’ medication histories, as revealed by SHiM, resulted in actual clinical consequences was then investigated. As this study was carried out during the observation phase of the clinical trial, results were not communicated to the medical teams. Main outcome measure Discrepancies between medication lists and whether these resulted in clinical consequences. Results SHiM was applied to 123 patients. The mean age of the participants was 78 (±6). 200 discrepancies were identified. 90 patients (73 %) had at least one discrepancy with a median of 1.0 discrepancies per patient (IQR 0.00–2.25). 53 (26.5 %) were classified as ‘unlikely to cause patient discomfort or clinical deterioration’, 145 (72.5 %) as ‘having potential to cause moderate discomfort or clinical deterioration’, and 2 (1 %) as ‘having potential to cause severe discomfort or clinical deterioration’. Of the 200 discrepancies identified, 2(1 %) resulted in adverse events. Conclusion The results suggest SHiM is an effective medications reconciliation tool and does identify discrepancies with potential for patient harm. However, it’s the capacity to prevent actual adverse events is less convincing.