Center-Level Variation in Hospitalization Costs of Lung Transplantation: A Contemporary Analysis

N. K.. Le¹, S. Mallick², N. Chervu³, J. Curry⁴, S. Kim², K. Ali², P. Benharash^5
1David Geffen School of Medicine at UCLA, Tarzana, California ²UCLA, Los Angeles, California ³UCLA David Geffen School of Medicine, Los Angeles, California ⁴David Geffen School of Medicine at UCLA, Los Angeles, California ⁵UCLA Division of Cardiac Surgery, Los Angeles, California

Purpose: Mitigating cost variation is crucial to the optimization of value-based healthcare delivery. However, there is a paucity of contemporary analyses examining cost variation for lung transplantation (LT). We used a national database to examine the presence of center-level variation in the costs of LT and its association with clinical outcomes.

Methods: This was a retrospective study of the 2016-2020 Nationwide Readmissions Database. All adult (≥18 years) hospitalizations for first-time, isolated unilateral or bilateral LT, within the first 2 days of admission, were abstracted. The primary outcome was hospitalization costs. Secondary outcomes included in-hospital mortality, perioperative complications, length of stay (LOS), nonhome discharge, and 30-day nonelective readmission.
To analyze center-level variation in costs, we developed a mixed-effects model, which included patient characteristics, operative characteristics, and lung disease diagnosis groups as fixed and hospital identifiers as a random effect. Operative characteristics consisted of single vs bilateral LT, and intraoperative cardiopulmonary bypass usage. The intraclass correlation coefficient (ICC) was calculated to quantify the proportion of variation in costs attributable to interhospital differences. Institutions within the highest quintile of risk-adjusted costs were classified as high-cost hospitals (HCH). Mixed regression models were developed to analyze the association between HCH and adjusted outcomes.

Results: An estimated 8,415 patients were included in this study. Between 2016 and 2020, the median cost of LT increased from $153,500 to $177,900. After risk adjustment, 15.4% of the explained variation in costs was attributable to hospital rather than patient factors (Figure 1).
Among the 8,415 transplants included, 1,133 (13.5%) occurred at HCH. Patients at HCH and non-High-Cost Hospitals (nHCH) were similar in the distribution of age, sex, burden of chronic conditions, insurance coverage, income, and transplant diagnosis groups. The two cohorts were also comparable in the proportion of bilateral LT and intraoperative cardiopulmonary bypass usage.
Compared to nHCH, HCH performed fewer annual cases (29 [20, 41] vs 41 [26, 69], p=0.003), but incurred an additional $103,300 in expenditures ($253,600 [174,300, 374,600] vs 150,300 [115,900, 202,000], p< 0.001). Relative to nHCH, patients treated at HCH exhibited higher rates of mortality, complications including stroke/transient ischemic attack, prolonged mechanical ventilation, acute renal failure requiring dialysis, and longer LOS. After risk adjustment, HCH remained associated with higher odds of mortality, complications, and an additional $98,100 in costs, but yielded lower likelihood for nonhome discharge, with nHCH as reference (Table 1).

Conclusion: We have identified significant cost variation in LT across the US with HCH performing fewer cases and having higher complications. With a rapid rise in the number of LT candidates, further examination of factors responsible for the observed variation is needed and may better inform future policy and reimbursement decisions.

Identify the source of the funding for this research project: None