The relationship of hospital market concentration, costs, and quality for major surgical procedures

Association of Hospital Market Competition with Outcomes of Complex Cancer Surgery

BACKGROUND

The association of hospital market competition, financial costs, and quality of oncologic care has not been well-defined. This study sought to evaluate variations in patient outcomes and financial expenditures after complex cancer surgery across high- and low-competition markets.

METHODS

Medicare 100% Standard Analytic Files were used to identify patients with lung, esophageal, gastric, hepatopancreaticobiliary, or colorectal cancer who underwent surgical resection between 2018 and 2021. Data were merged with the annual hospital survey database, and the hospital market Herfindahl-Hirschman index was used to categorize hospitals into low- and high-concentration markets. Multi-level, multivariable regression models adjusting for patient characteristics (i.e., age, sex, comorbidities, and social vulnerability), year of procedure, and hospital factors (i.e., case volume, nurse-bed ratio, and teaching status) were used to assess the association between hospital market competition and outcomes.

RESULTS

Among 117,641 beneficiaries who underwent complex oncologic surgery, the mean age was 73.8 ± 6.1 years, and approximately one-half of the cohort was male (n = 56,243, 47.8%). Overall, 63.8% (n = 75,041) of the patients underwent care within a high-competition market. Notably, there was marked geographic variation relative to market competition. High versus low market-competition hospitals were more likely to be in high social vulnerability areas (35.1 vs 27.5%; p < 0.001), as well as care for racial/ethnic minority individuals (13.8 vs 7.7%; p < 0.001), and patients with more comorbidities (≥ 2 Elixhauser comorbidities: 63.1 vs 61.1%; p < 0.001). In the multivariable analysis, treatment at hospitals in high- versus low-competition markets was associated with lower odds of achieving a textbook outcome (odds ratio, 0.95; 95% confidence interval, 0.91-0.99; p = 0.009). Patients at high-competition hospitals had greater mean index hospitalization costs ($19,462.2 [16211.9] vs $18,844.7 [14994.7]) and 90-day post-discharge costs ($7807.8 [15431.3] vs $7332.8 [14038.2]) (both p < 0.001) than individuals at low-competition hospitals.

CONCLUSIONS

Hospital market competition was associated with poor achievement of an optimal postoperative outcome and greater hospitalization costs.

Outcomes for High-Risk Surgical Procedures Across High- and Low-Competition Hospital Markets

Importance

Maintaining competition among hospitals is increasingly seen as important to achieving high-quality outcomes. Whether or not there is an association between hospital market competition and outcomes after high-risk surgery is unknown.

Objective

To evaluate whether there is an association between hospital market competition and outcomes after high-risk surgery.

Design, Setting, and Participants

We performed a retrospective study of Medicare beneficiaries who received care in US hospitals. Participants were 65 years and older who electively underwent 1 of 10 high-risk surgical procedures from 2015 to 2018: carotid endarterectomy, mitral valve repair, open aortic aneurysm repair, lung resection, esophagectomy, pancreatectomy, rectal resection, hip replacement, knee replacement, and bariatric surgery. Hospitals were categorized into high-competition and low-competition markets based on the hospital market Herfindahl-Hirschman index. Comparisons of 30-day mortality and 30-day readmissions were risk-adjusted using a multivariate logistic regression model adjusting for patient factors (age, sex, comorbidities, and dual eligibility), year of procedure, and hospital characteristics (nurse ratio and teaching status). Data were analyzed from May 2022 to March 2023.

Main Outcomes and Measures

Thirty-day postoperative mortality and readmissions.

Results

A total of 2 242 438 Medicare beneficiaries were included in the study. The mean (SD) age of the cohort was 74.1 (6.4) years, 1 328 946 were women (59.3%), and 913 492 were men (40.7%). When examined by procedure, compared with low-competition hospitals, high-competition market hospitals demonstrated higher 30-day mortality for 2 of 10 procedures (mitral valve repair: odds ratio [OR], 1.11; 95% CI, 1.07-1.14; and carotid endarterectomy: OR, 1.06; 95% CI, 1.03-1.09) and no difference for 5 of 10 procedures (open aortic aneurysm repair, bariatric surgery, esophagectomy, knee replacement, and hip replacement; ranging from OR, 0.97; 95% CI, 0.94-1.00, for hip replacement to OR, 1.09; 95% CI, 0.94-1.26, for bariatric surgery). High-competition hospitals also demonstrated 30-day readmissions that were higher for 5 of 10 procedures (open aortic aneurysm repair, knee replacement, mitral valve repair, rectal resection, and carotid endarterectomy; ranging from OR, 1.01; 95% CI, 1.00-1.02, for knee replacement to OR, 1.05; 95% CI, 1.02-1.08, for rectal resection) and no difference for 3 procedures (bariatric surgery: OR, 1.03; 95% CI, 0.99-1.07; esophagectomy: OR, 1.02; 95% CI, 0.99-1.06; and pancreatectomy: OR, 1.00; 95% CI, 0.99-1.01). Hospitals in high-competition compared with low-competition markets cared for patients who were older (mean [SD] age of 74.4 [6.6] years vs 74.0 [6.2] years, respectively; P < .001), were more likely to be racial and ethnic minority individuals (77 322/450 404 [17.3%] vs 23 328/444 900 [5.6%], respectively; P < .001), and had more comorbidities (≥2 Elixhauser comorbidities, 302 415/450 404 [67.1%] vs 284 355/444 900 [63.9%], respectively; P < .001).

Conclusions and Relevance

This study found that hospital market competition was not consistently associated with improved outcomes after high-risk surgery. Efforts to maintain hospital market competition may not achieve better postoperative outcomes.