Newly Published
Perioperative Medicine  |   February 2018
Association of Polypharmacy with Survival, Complications, and Healthcare Resource Use after Elective Noncardiac Surgery: A Population-based Cohort Study
Author Notes
  • From the Departments of Anesthesiology and Pain Medicine (D.I.M., G.L.B.) and Internal Medicine (C.v.W.) and the School of Epidemiology and Public Health (D.I.M., C.v.W.), University of Ottawa, Ottawa, Ontario, Canada; the Departments of Anesthesiology and Pain Medicine (D.I.M., G.L.B.) and Internal Medicine (C.v.W.) and the Research Institute (D.I.M., G.L.B., C.v.W.), The Ottawa Hospital, Ottawa, Ontario, Canada; and the Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada (D.I.M., C.A.W., C.v.W.).
  • Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are available in both the HTML and PDF versions of this article. Links to the digital files are provided in the HTML text of this article on the Journal’s Web site (www.anesthesiology.org).
    Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are available in both the HTML and PDF versions of this article. Links to the digital files are provided in the HTML text of this article on the Journal’s Web site (www.anesthesiology.org).×
  • Submitted for publication June 14, 2017. Accepted for publication January 9, 2018.
    Submitted for publication June 14, 2017. Accepted for publication January 9, 2018.×
  • Research Support: Dr. McIsaac receives salary support from the Department of Anesthesiology, Ottawa Hospital (Ottawa, Ontario, Canada) and the Canadian Anesthesiology Society’s Career Scientist Award. This study was also supported by the Institute for Clinical Evaluative Sciences (Toronto, Canada), which is funded by an annual grant from the Ontario Ministry of Health and Long-term Care (Toronto, Canada). The opinions, results, and conclusions reported in this paper are those of the authors and are independent from the funding sources. No endorsement by Institute for Clinical Evaluative Sciences or the Ontario Ministry of Health and Long-term Care is intended or should be inferred. These data sets were held securely in a linked, deidentified form, and were analyzed at the Institute for Clinical Evaluative Sciences.
    Research Support: Dr. McIsaac receives salary support from the Department of Anesthesiology, Ottawa Hospital (Ottawa, Ontario, Canada) and the Canadian Anesthesiology Society’s Career Scientist Award. This study was also supported by the Institute for Clinical Evaluative Sciences (Toronto, Canada), which is funded by an annual grant from the Ontario Ministry of Health and Long-term Care (Toronto, Canada). The opinions, results, and conclusions reported in this paper are those of the authors and are independent from the funding sources. No endorsement by Institute for Clinical Evaluative Sciences or the Ontario Ministry of Health and Long-term Care is intended or should be inferred. These data sets were held securely in a linked, deidentified form, and were analyzed at the Institute for Clinical Evaluative Sciences.×
  • Competing Interests: The authors declare no competing interests.
    Competing Interests: The authors declare no competing interests.×
  • Correspondence: Address correspondence to Dr. McIsaac: Ottawa Hospital, 1053 Carling Avenue, Room B311, Ottawa, Ontario K1Y 4E9, Canada. dmcisaac@toh.ca. Information on purchasing reprints may be found at www.anesthesiology.org or on the masthead page at the beginning of this issue. Anesthesiology’s articles are made freely accessible to all readers, for personal use only, 6 months from the cover date of the issue.
Article Information
Perioperative Medicine / Pharmacology
Perioperative Medicine   |   February 2018
Association of Polypharmacy with Survival, Complications, and Healthcare Resource Use after Elective Noncardiac Surgery: A Population-based Cohort Study
Anesthesiology Newly Published on February 13, 2018. doi:10.1097/ALN.0000000000002124
Anesthesiology Newly Published on February 13, 2018. doi:10.1097/ALN.0000000000002124
Abstract

Background: Polypharmacy is increasingly prevalent in older patients and is associated with adverse events among medical patients. The impact of polypharmacy on outcomes after elective surgery is poorly described. The authors’ objective was to measure the association of polypharmacy with survival, complications, and resource use among older patients undergoing elective surgery.

Methods: After registration (NCT03133182), the authors identified all individuals older than 65 yr old having their first elective noncardiac surgery in Ontario, Canada, between 2002 and 2014. Using linked administrative data, the authors identified all prescriptions dispensed in the 90 days before surgery and classified people receiving five or more unique medications with polypharmacy. The associations of polypharmacy with 90-day survival (primary outcome), complications, length of stay, costs, discharge location, and readmissions were estimated after multilevel, multivariable adjustment for demographics, comorbidities, previous healthcare use, and surgical factors. Prespecified and post hoc sensitivity analyses were also performed.

Results: Of 266,499 patients identified, 146,026 (54.8%) had polypharmacy. Death within 90 days occurred in 4,356 (3.0%) patients with polypharmacy and 1,919 (1.6%) without (adjusted hazard ratio = 1.21; 95% CI, 1.14 to 1.27). Sensitivity analyses demonstrated no increase in effect when only high-risk medications were considered and attenuation of the effect when only prescriptions filled in the 30 preoperative days were considered (hazard ratio = 1.07). Associations were attenuated or not significant in patients with frailty and higher comorbidity scores.

Conclusions: Older patients with polypharmacy represent a high-risk stratum of the perioperative population. However, the authors’ findings call into question the causality and generalizability of the polypharmacy-adverse outcome association that is well documented in nonsurgical patients.