Nair NP, et al. - The physicians performed this retrospective study to examine the occurrence of repeat adverse drug reaction-related hospital admissions in elderly patients within 12 months of an adverse drug reaction-related admission to a medical ward. In addition, they investigated whether a validated adverse drug reaction score could be useful in identifying patients at higher risk of a repeat adverse drug reaction-related hospitalization. There was a repeat admission for an adverse drug reaction within 12 months of discharge in 1/8 elderly patients who were hospitalized due to an adverse drug reaction. The PADR-EC (Prediction of Hospitalization due to Adverse Drug Reactions in Elderly Community-Dwelling Patients) score could potentially be used at hospital discharge to prioritize patients for interventions to prevent subsequent adverse drug reaction-related hospital admissions.

• In order to identify repeat adverse drug reaction-related hospital admissions within 12 months of discharge, the physicians followed elderly participants who were hospitalized with an adverse drug reaction from their earlier study [the PADR-EC (Prediction of Hospitalization due to Adverse Drug Reactions in Elderly Community-Dwelling Patients) study].
• The PADR-EC score presented as the sum of points assigned to 5 significant predictors of adverse drug reaction-related hospitalisation: antihypertensive use, renal failure, dementia, inappropriate anticholinergic use and drug changes in the preceding 3 months.
• They evaluated the causality, preventability and severity of each adverse drug reaction-related repeat admission within the 12-month follow-up.

• There was an occurrence of adverse drug reaction-related repeat admissions after 13.4% (n = 15) of the 112 adverse drug reaction-related index admissions.
• Compared to patients who were not readmitted (median PADR-EC score 7, interquartile range 5–7, p = 0.034), patients with a repeat adverse drug reaction-related admission had significantly higher PADR-EC scores at discharge of their index admission (median PADR-EC score 7, interquartile range 7–9).
• Most (73.3%) adverse drug reaction-related repeat admissions were considered ‘preventable’.
• In all cases, adverse drug reaction severity was ‘moderate’.
• The most common adverse drug reactions were renal disorders (44.4%).
• Diuretics (44.8%) were the most frequently implicated drug classes.
• It was found that all adverse drug reaction-related repeat admissions were ‘probable’.