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.