Mortality After Total Knee and Total Hip Arthroplasty in a Large Integrated Health Care System

CONTEXT: The number of excess deaths associated with elective total joint arthroplasty in the US is not well understood.

OBJECTIVE: To evaluate one-year postoperative mortality among patients with elective primary and revision arthroplasty procedures of the hip and knee.

DESIGN: A retrospective analysis was conducted of hip and knee arthroplasties performed in 2010. Procedure type, procedure volume, patient age and sex, and mortality were obtained from an institutional total joint replacement registry. An integrated health care system population was the sampling frame for the study subjects and was the reference group for the study.

MAIN OUTCOME MEASURES: Standardized 1-year mortality ratios (SMRs) and 95% confidence intervals (CIs) were calculated.

RESULTS: A total of 10,163 primary total knee arthroplasties (TKAs), 4963 primary total hip arthroplasties (THAs), 606 revision TKAs, and 496 revision THAs were evaluated. Patients undergoing primary THA (SMR = 0.6, 95% CI = 0.4-0.7) and TKA (SMR = 0.4, 95% CI = 0.3-0.5) had lower odds of mortality than expected. Patients with revision TKA had higher-than-expected mortality odds (SMR = 1.8, 95% CI = 1.1-2.5), whereas patients with revision THA (SMR = 0.9, 95% CI = 0.4-1.5) did not have higher-than-expected odds of mortality.

CONCLUSION: Understanding excess mortality after joint surgery allows clinicians to evaluate current practices and to determine whether certain groups are at higher-than-expected mortality risk after surgery.