title: Adverse drug reactions in older patients during hospitalisation: are they predictable?
abstract: BACKGROUND
  adverse drug reactions (ADRs) are a major cause of morbidity and healthcare utilisation in older people. The GerontoNet ADR risk score aims to identify older people at risk of ADRs during hospitalisation. We aimed to assess the clinical applicability of this score and identify other variables that predict ADRs in hospitalised older people.
  
  
  METHODS
  we prospectively studied 513 acutely ill patients aged ≥65 years. The GerontoNet ADR risk score was calculated for all patients. ADRs were identified through patient and physician consultation together with analysis of case notes. Receiver operator characteristic (ROC) curves were constructed to test the ability of the GerontoNet risk score to predict ADRs. Multivariate logistic regression examined the influence of individual variables on the presence of ADRs.
  
  
  RESULTS
  in-hospital ADRs were identified in 135 patients (26%). The area under the ROC curve was 0.62 (95% CI: 0.57-0.68). Variables which increased ADR risk include (i) renal failure (OR: 1.81, 95% CI: 1.12-2.92), (ii) increasing number of medications (OR: 1.09, 95% CI: 1.02-1.17) (iii) inappropriate medications (OR: 2.40, 95% CI: 1.26-4.50) and (iv) age ≥75 years (OR: 2.12, 95% CI: 1.23-3.70).
  
  
  CONCLUSIONS
  the GerontoNet ADR risk score incorrectly classified 38% of patients as low risk. Inappropriate medications and increasing age also contribute to ADR risk.
authors.affiliation: Department of Geriatric Medicine, Cork University Hospital, Wilton, Cork, Ireland. oconnormarienoelle@gmail.com
authors.forename: Marie N
authors.initials: MN
authors.lastname: O'Connor
authors.forename: Paul
authors.initials: P
authors.lastname: Gallagher
authors.forename: Stephen
authors.initials: S
authors.lastname: Byrne
authors.forename: Denis
authors.initials: D
authors.lastname: O'Mahony
mesh_terms: D016907:Adverse Drug Reaction Reporting Systems / Q000592:standards*; D000368:Aged; D000369:Aged, 80 and over; D064420:Drug-Related Side Effects and Adverse Reactions / Q000453:epidemiology*; D005260:Female; D015577:Geriatric Assessment / Q000379:methods*; D006760:Hospitalization / Q000706:statistics & numerical data*; D006784:Hospitals, Teaching; D006801:Humans; D007297:Inpatients / Q000706:statistics & numerical data*; D007494:Ireland; D016015:Logistic Models; D008297:Male; D010817:Physician-Patient Relations; D011446:Prospective Studies; D012372:ROC Curve; D015203:Reproducibility of Results; D012307:Risk Factors