Abstract
INTRODUCTION
Utilization of a patient management support system in our clinical pathway has been successfully demonstrated to both reduce the length of hospital stay after primary THA, as well as reducing the number of hospital readmissions. While successful in a general patient population, the ability of a patient management support system to reduce readmissions in subsets of high risk THA patients has not been evaluated.
METHODS
We identified all primary THAs performed at a single institution between 2013 and 2015. Patient sex, age at the time of surgery, race, ASA grade, and 120-day readmissions were retrieved from the patient medical record. Similar to previous studies, the patient's home address was used as a proxy for socioeconomic status, with the estimated median income of a given patient being estimated as the median household income for patients of similar ethnicity living within their zip code as reported in the 2014 U.S. Census. A binary regression was used to determine if a model of patient factors (age, sex, race, socioeconomic status, and/or ASA grade) could accurately predict 120-day readmission after primary THA. Age and socioeconomic status were treated as a continuous variable and all other factors were categorical in nature, and the individual effects of each categorical factor on readmissions were also assessed.
RESULTS
A sample of 889 primary THAs was identified using the above criteria, of which 754 (84.8%) were Caucasian and 124 (13.9%) were African Americans. Eleven patients (1.2%) either self-reported a different race or race was unknown. Due to the small number of patients in the other/unknown group, this subset was not included in our analysis. With the remaining sample of 878 THAs (475 females, 403 males; age 62.1 ± 13.0 years), a model containing age, sex, race, socioeconomic status, and ASA grade was unable to accurately predict the need for hospital readmission (R2 = 0.02). When assessed individually, the rates of hospital readmission did not differ by sex or race; however, those with ASA grades I or II had significantly lower readmission rates than patients with ASA grades III or IV (Table 1).
DISCUSSION AND CONCLUSION
Despite a comprehensive program, the risk of readmission for patients with greater comorbidity burdens was double that of patients with low ASA grades.
