title: Inappropriate drug use in elderly patients is associated with prolonged hospital stay and increased postoperative mortality after colorectal cancer surgery: a population-based study.
abstract: OBJECTIVE
  The study aimed to investigate whether continuing potentially inappropriate medication (PIM) is associated with length of hospital stay (LOS) and postoperative mortality in elderly people undergoing colorectal cancer surgery.
  
  
  METHODS
  The Swedish National Colorectal Cancer Register and the Swedish Prescribed Drug Register provided matched data on 7279 patients aged 75 years or more who had undergone bowel resection for colorectal cancer between 2007 and 2010. Patients were divided into two groups depending on whether or not they were taking PIM at the time of surgery. The primary efficacy variables were the LOS and 30-day postoperative mortality.
  
  
  RESULTS
  Of the 7279 patients, 22.5% (1641) of the patients were exposed to at least one PIM and the total number of drugs taken in this group was six, compared with three in the non-PIM group (P < 0.001). Postoperative mortality was higher in the PIM group (7.1% vs 4.5%, P < 0.001), and LOS was longer (10 days vs 9, P = 0.001). When adjusted for independent predictors, the differences in LOS (odds ratio 1.14; 95% confidence interval 1.00-1.29, P = 0.046) and postoperative mortality (odds ratio 1.43; 95% confidence interval 1.11-1.85, P = 0.006) remained significant.
  
  
  CONCLUSIONS
  The use of PIM prior to surgery is associated with increased postoperative mortality and prolonged hospital stay. Although no causal relationship is proved, the results add a further aspect to preoperative optimization of elderly patients about to have major colorectal surgery.
authors.affiliation: Department of Clinical Science, Intervention and Technology, CLINTEC, Stockholm, Sweden.|Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.|Department of Geriatrics, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: K S
authors.identifier: http://orcid.org/0000-0002-3251-9363
authors.initials: KS
authors.lastname: Samuelsson
authors.affiliation: Department of Clinical Science, Intervention and Technology, CLINTEC, Stockholm, Sweden.|Center for Digestive Diseases, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Egenvall
authors.affiliation: Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.|Department of Geriatrics, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: I
authors.initials: I
authors.lastname: Klarin
authors.affiliation: Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.|Department of Geriatrics, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Lökk
authors.affiliation: Department of Clinical Science, Intervention and Technology, CLINTEC, Stockholm, Sweden.|Center for Digestive Diseases, Karolinska University Hospital, Stockholm, Sweden.|Department of Surgery and Perioperative Sciences, Umeå University, Stockholm, Sweden.
authors.forename: U
authors.initials: U
authors.lastname: Gunnarsson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003082:Colectomy / Q000401:mortality*; D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000601:surgery*; D005260:Female; D006801:Humans; D057970:Inappropriate Prescribing / Q000009:adverse effects*; D007902:Length of Stay / Q000706:statistics & numerical data*; D008297:Male; D016017:Odds Ratio; D011184:Postoperative Period; D000067561:Potentially Inappropriate Medication List / Q000706:statistics & numerical data*; D057234:Preoperative Period; D011446:Prospective Studies; D012042:Registries; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology
keywords: Potentially inappropriate drug use; colorectal cancer surgery; elderly; length of hospital stay; postoperative mortality