Factors Influencing Discharge Destination After Total Knee Arthroplasty: A Database Analysis

The demand for total knee arthroplasty (TKA) continues to challenge hospital financial resources. Hospitals have countered this economic demand by reducing patient length of stay (LoS), thus requiring a higher utilization of extended care facilities (ECF) and home with home health care (HHC). With an increase in the number of insured low-income families following the Affordable Care Act (ACA), TKA patients' demographics are anticipated to change. Both trends have significant economic implications, and predicting the discharge destinations of TKA patients would help plan for future health expenditures. The purpose of this study was to determine which variables are significant in predicting discharge destinations of patients treated with TKA.

We utilized the California Hospital Discharge data set of the year 2010. For each hospitalization, the data set includes information about patient demographics (age, gender, race, and ethnicity), insurance type, diagnoses and procedures, and patient disposition. Discharge to home was the reference category. Discharges to a skilled nursing home and discharge to home with home care were the 2 additional alternatives. Independent variables included the Charlson comorbidity index, payer category (private, Medicare, Medical, and other), race, ethnicity, age, and gender.

Over 28 611 TKAs were reviewed with 45.9% discharged to HHC, 29.9% going to ECF, and 24.2% going home without home health care. Race, age, insurance, and morbidity proved to be highly significant factors influencing patient discharge destination (P < .001). Medicare coverage relative to private payers was a strong predictor for discharge destination (relative risk ratio (RRR) 1.69, P < .001). The strongest predictors were black and Asian races relative to whites (RRR 1.54, P < .01). Male gender was the only factor that lowered the risk of discharge to a nursing home (RRR 0.43, P < .001).

This study provides insight on which patient characteristics influence discharge destination after TKA. Race, age, insurance, and morbidity were highly significant (P < .001) factors on patient discharge destination.