title: Polypharmacy cut-points in older people with cancer: how many medications are too many?
abstract: OBJECTIVE
  Polypharmacy is often defined as use of 'five-or-more-medications'. However, the optimal polypharmacy cut-point for predicting clinically important adverse events in older people with cancer is unclear. The aim was to determine the sensitivities and specificities of a range of polypharmacy cut-points in relation to a variety of adverse events in older people with cancer.
  
  
  METHODS
  Data on medication use, falls and frailty criteria were collected from 385 patients aged ≥70 years presenting to a medical oncology outpatient clinic. Receiver operating characteristic (ROC) curves were produced to examine sensitivities and specificities for varying definitions of polypharmacy in relation to exhaustion, falls, physical function, Karnofsky Performance Scale (KPS) and frailty. Sub-analyses were performed when stratifying by age, sex, comorbidity status and analgesic use.
  
  
  RESULTS
  Patients had a mean age of 76.7 years. Using Youden's index, the optimal polypharmacy cut-point was 6.5 medications for predicting frailty (specificity 67.0 %, sensitivity 70.0 %), physical function (80.2 %, 49.3 %) and KPS (69.8 %, 52.1 %), 5.5 for falls (59.2 %, 73.0 %) and 3.5 for exhaustion (43.4 %, 74.5 %). For polypharmacy defined as five-or-more-medications, the specificities and sensitivities were frailty (44.9 %, 77.5 %), physical function (58.0 %, 69.7 %), KPS (47.7 %, 69.4 %), falls (44.5 %, 75.7 %) and exhaustion (52.6 %, 64.1 %). The optimal polypharmacy cut-points were similar when the sample was stratified by age, sex, comorbidity status and analgesic use.
  
  
  CONCLUSIONS
  Our results suggest that no single polypharmacy cut-point is optimal for predicting multiple adverse events in older people with cancer. In this population, the common definition of five-or-more-medications is reasonable for identifying 'at-risk' patients for medication review.
authors.affiliation: Centre for Medicine Use and Safety, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, 3052, Melbourne, VIC, Australia. Justin.Turner@unisa.edu.au.|School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, Australia. Justin.Turner@unisa.edu.au.|Department of Clinical Pharmacology, Royal Adelaide Hospital, Adelaide, SA, Australia. Justin.Turner@unisa.edu.au.
authors.forename: Justin P
authors.initials: JP
authors.lastname: Turner
authors.affiliation: Centre for Medicine Use and Safety, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, 3052, Melbourne, VIC, Australia.|NHMRC Cognitive Decline Partnership Centre, Hornsby Ku-ring-gai Hospital, University of Sydney, Sydney, NSW, Australia.
authors.forename: Kris M
authors.initials: KM
authors.lastname: Jamsen
authors.affiliation: Department of Clinical Pharmacology, Royal Adelaide Hospital, Adelaide, SA, Australia.
authors.forename: Sepehr
authors.initials: S
authors.lastname: Shakib
authors.affiliation: Department of Medical Oncology, Royal Adelaide Hospital, Adelaide, SA, Australia.|School of Medicine, Adelaide University, Adelaide, SA, Australia.
authors.forename: Nimit
authors.initials: N
authors.lastname: Singhal
authors.affiliation: Department of Geriatric and Rehabilitation Medicine, Royal Adelaide Hospital, Adelaide, SA, Australia.
authors.forename: Robert
authors.initials: R
authors.lastname: Prowse
authors.affiliation: Centre for Medicine Use and Safety, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, 3052, Melbourne, VIC, Australia.|School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, Australia.|NHMRC Cognitive Decline Partnership Centre, Hornsby Ku-ring-gai Hospital, University of Sydney, Sydney, NSW, Australia.
authors.forename: J Simon
authors.initials: JS
authors.lastname: Bell
mesh_terms: D000058:Accidental Falls / Q000706:statistics & numerical data; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D005221:Fatigue / Q000139:chemically induced; D005260:Female; D015577:Geriatric Assessment / Q000706:statistics & numerical data*; D006801:Humans; D017567:Karnofsky Performance Status; D008297:Male; D009369:Neoplasms / Q000188:drug therapy*; D019338:Polypharmacy; D012372:ROC Curve; D012015:Reference Standards; D012680:Sensitivity and Specificity
keywords: Aged; Cancer; Deprescribing; Polypharmacy