Time Trends and Risk Factors for 30-Day Adverse Events in Black Patients Undergoing Primary Total Knee Arthroplasty.

Background: Increased adverse events (AEs) have been reported among black patients undergoing joint arthroplasty, but little is known about their persistence and risk factors. The purpose of this study is (1) to examine recent annual trends in 30-day outcomes after total knee arthroplasty (TKA) and (2) to develop a preoperative risk stratification model in this racial minority.

Methods: The American College of Surgeons National Surgical Quality Improvement Program was queried for all black/African American patients who underwent primary TKA between 2011 and 2017. Time trends in demographic variables, comorbid conditions, perioperative characteristics, length of stay (LOS), and 30-day readmissions, reoperations, medical complications, surgical complications, and mortality were assessed. Multivariate logistic regression analyses were performed to identify independent risk factors for development of 30-day AEs.

Results: In total, 19,496 black patients were analyzed. Between 2011 and 2017, there have been improved comorbidity profiles (P < .02), decreased LOS (P < .001), and lower rates of AEs (P < .001). Significant risk factors for developing AEs were male gender, tobacco smoking, American Society of Anesthesiologists score >2, dependent functional status, congestive heart failure, chronic obstructive pulmonary disease, metastatic cancer, dyspnea, chronic kidney disease, bilateral TKA, and operative time >100 minutes.

Conclusion: There have been significant improvements in the annual trends of LOS and 30-day outcomes among black patients undergoing primary TKA in recent years. A predictive model for 30-day AEs was developed to help guide risk stratification and optimization of modifiable factors, namely anemia, tobacco smoking, bilateral surgery, and operative time.