Demographics of Patients Traveling Notable Distances to Receive Total Knee Arthroplasty

A Nationwide Analysis of the Impact of Socioeconomic Status on Complications and Health Care Utilizations After Total Knee Arthroplasty Using the Area Deprivation Index: Consideration of the Disadvantaged Patient

BACKGROUND

Socioeconomic status has been demonstrated to be an important prognostic risk factor among patients undergoing total joint arthroplasty. We evaluated patients living near neighborhoods with higher socioeconomic risk undergoing total knee arthroplasty (TKA) and if they were associated with differences in the following: (1) medical complications; (2) emergency department (ED) utilizations; (3) readmissions; and (4) costs of care.

METHODS

A query of a national database from 2010 to 2020 was performed for primary TKAs. The Area Deprivation Index (ADI) is a weighted index comprised of 17 census-based markers of material deprivation and poverty. Higher numbers indicate a greater disadvantage. Patients undergoing TKA in zip codes associated with high ADI (90%+) were 1:1 propensity-matched to a comparison group by age, sex, and Elixhauser Comorbidity Index. This yielded 225,038 total patients, evenly matched between cohorts. Outcomes studied included complications, ED utilizations, readmission rates, and 90-day costs. Logistic regression models computed the odds ratios (OR) of ADI on the dependent variables. P values less than .003 were significant.

RESULTS

High ADI led to higher rates and odds of any medical complications (11.7 versus 11.0%; OR: 1.05, P = .0006), respiratory failures (0.4 versus 0.3%; OR: 1.28, P = .001), and acute kidney injuries (1.7 versus 1.5%; OR: 1.15, P < .0001). Despite lower readmission rates (2.9 versus 3.5%), high ADI patients had greater 90-day ED visits (4.2 versus 4.0%; OR: 1.07, P = .0008). The 90-day expenditures ($15,066 versus $12,459; P < .0001) were higher in patients who have a high ADI.

CONCLUSIONS

Socioeconomically disadvantaged patients have increased complications and ED utilizations. Neighborhood disadvantage may inform health care policy and improve postdischarge care. The socioeconomic status metrics, including ADI (which captures community effects), should be used to adequately risk-adjust or risk-stratify patients so that access to care for deprived regions and patients is not lost.

LEVEL OF EVIDENCE

III.

Early Clinical Outcomes of "Lemon-Dropped" Complex Primary Total Joint Arthroplasty Patients to a Tertiary Care Center

BACKGROUND

In the era of value-based care, pressures lead to cherry-picking healthier patients and lemon-dropping riskier patients to higher levels-of-care. This study examined whether "lemon-dropped" primary total joint arthroplasty (pTJA) patients require increased health care resources and experience worse outcomes.

METHODS

This was a retrospective cohort study of all pTJAs at one tertiary care center in 2022, excluding bilaterals, acute fractures, oncologic cases, and conversion hips. Patients were classified via referral pattern as simple or complex (referred for medical or surgical complexity). Primary outcomes were implant costs and any emergency department visit, readmission, reoperation, or complication within 90 days. Secondary outcomes were distance traveled to the hospital, anesthesia type, estimated blood loss, case duration, time in the recovery unit, length of stay, and discharge disposition. Outcomes were assessed via electronic medical record review and analyzed via Fisher's exact and unpaired Welch's t-tests.

RESULTS

In total 641 pTJAs (322 hips, 319 knees) met inclusion criteria; 10.3% were complex referrals. Complex patients were younger (59 versus 66 years, P < .05) and more often non-White (41 versus 31%, P < .001), non-English speaking (11 versus 7%, P < .001), and had nonprimary osteoarthritis as a surgical indication (59 versus 12%, P < .001), but had similar Charlson Comorbidity Index and American Society of Anesthesiologists scores. Complex patients had increased odds of 90-day emergency department visits (OR [odds ratio] = 2.11, P = .04), 90-day complications (OR = 2.63, P < .001), and non-home discharge (OR = 2.60, P = .006); higher mean relative implant costs (1.31x, P < .001); longer time in the operating room (181 versus 158 minutes P < .001), time in surgery (125 versus 105 minutes, P < .001), and length of stay (3.2 versus 1.7 days, P = .005).

CONCLUSIONS

"Lemon-dropped" pTJAs had worse early clinical outcomes and higher health care utilization, despite a control group with patients ill enough to utilize a tertiary care center as their medical home. Reimbursement models and evaluation metrics must account for these differences.