title: Association between Withholding Angiotensin Receptor Blockers in the Early Postoperative Period and 30-day Mortality: A Cohort Study of the Veterans Affairs Healthcare System.
abstract: BACKGROUND
  Despite widespread use, there is limited information to guide perioperative management of angiotensin receptor blockers (ARBs).
  
  
  METHODS
  In this retrospective cohort study, the authors evaluated the patterns of postoperative ARB use in veterans regularly prescribed ARBs admitted for noncardiac surgery at the Veterans Affairs Healthcare system between 1999 and 2011. Multivariable and propensity score-matched Cox proportional hazards models were used to determine the independent effect of failure to resume ARB by postoperative day 2 on the primary outcome of all-cause 30-day mortality.
  
  
  RESULTS
  Out of 1,167,482 surgical admissions, 30,173 inpatient surgical admissions met inclusion criteria. Approximately 10,205 patients (33.8%) in the cohort did not resume ARB by day 2. Those that resumed ARB had a 30-day mortality rate of 1.3% (260 of 19,968), whereas 3.2% (323 of 10,205) died in the group that withheld ARB. The unadjusted hazard ratio (HR) for 30-day mortality was 2.45 (95% CI, 2.08 to 2.89; P < 0.001) for those that withheld ARB compared with those that resumed, whereas the multivariable adjusted HR was 1.74 (95% CI, 1.47 to 2.06; P < 0.001). When restricted to a propensity score-matched subset of 19,490, the HR was similar (1.47; 95% CI, 1.22 to 1.78; P < 0.001). Withholding ARB in younger patients increased mortality risk (HR = 2.52; 95% CI, 1.69 to 3.76; P < 0.001 for age <60 yr) compared with older patients (HR = 1.42; 95% CI, 1.09 to 1.85; P = 0.01 for age >75 yr).
  
  
  CONCLUSIONS
  Postoperative delay in resuming ARB is common, particularly in patients who are frail after surgery. Withholding ARB is strongly associated with increased 30-day mortality, especially in younger patients, although residual confounding may be present.
authors.affiliation: From the Department of Anesthesia and Perioperative Care, University of California, San Francisco, San Francisco, California, and San Francisco Veterans Affairs Medical Center, San Francisco, California.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Lee
authors.forename: Steven
authors.initials: S
authors.lastname: Takemoto
authors.forename: Arthur W
authors.initials: AW
authors.lastname: Wallace
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D057911:Angiotensin Receptor Antagonists / Q000008:administration & dosage*; D015331:Cohort Studies; D005260:Female; D006787:Hospitals, Veterans / Q000639:trends*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009026:Mortality / Q000639:trends; D011182:Postoperative Care / Q000401:mortality* / Q000639:trends*; D012189:Retrospective Studies; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D014493:United States Department of Veterans Affairs / Q000639:trends*; D028761:Withholding Treatment / Q000639:trends*
chemical_list: D057911:Angiotensin Receptor Antagonists