Prioritizing high-volume repair hospitals with ruptured abdominal aortic aneurysms, for rural and nonrural patients.

BACKGROUND: Among patients who suffer a ruptured abdominal aortic aneurysm (rAAA), ≤35% die perioperatively despite advancements in endovascular repair and intensive care. Patient rurality and associated disparities in local health services portend poorer cardiovascular outcomes; however, the effect of patient rurality on rAAA outcomes is unknown. Conversely, high-volume repair hospitals are associated with improved mortality outcomes for cardiovascular operations; however, the effects for patients residing rurally are unknown. We evaluated the association between in-hospital mortality, patient rurality, transfer status, and rAAA hospital repair volume among patients undergoing rAAA repair.

METHODS: Using Healthcare Cost and Utilization Project's State Inpatient Database (New York and Florida), we identified adults with a primary diagnosis of rAAA who underwent repair (2015-2020). Exposures of interest included (1) patient rurality, (2) transfer status before repair, and (3) hospital rAAA repair volume. The Rural Urban Community Area classified patient residence as rural (rural/small town/micropolitan) or nonrural (metropolitan), the State Inpatient Database provided transfer status from another facility, and the top 25% of hospital rAAA volume defined high-volume repair hospitals. The primary outcome was in-hospital mortality. A multivariable logistic regression adjusted for patient demographics, comorbidities, frailty (by validated the Risk Analysis Index), income quartiles, repair type, and hospital case mix with a variance estimation clustered by unique hospital. Interaction terms evaluated the association between hospital repair volume and mortality among exposure subgroups.

RESULTS: Of 1744 rAAA patients (median age, 75 years [interquartile range, 67-82 years]; 76.4% male; 78.8% White; 73.9% undergoing endovascular aneurysm repair), 148 (8.5%) resided in rural areas, 414 (23.7%) were transferred to a referral hospital for repair, and 1248 (71.6%) were repaired at high-volume hospitals. Rural patients were more often transferred in from another facility for repair (49.3% vs 21.4%; P < .001) and repaired at high-volume hospitals (82.6% vs 70.6%; P = .002). After multivariable adjustment, neither rurality (adjusted odds ratio [aOR], 0.78; 95% confidence interval [CI], 0.46-1.34) nor transfer status (aOR, 0.82; 95% CI, 0.61-1.10) were associated with in-hospital mortality; however, high-volume hospitals were associated with a 27% lower risk of in-hospital mortality (aOR, 0.73; 95% CI, 0.56-0.96). The association between high-volume repair hospitals and reduced in-hospital mortality was independent of rural residence and transfer status.

CONCLUSIONS: Despite rural patients having fewer local health care resources, rurality was not associated with an increased risk of in-hospital mortality after rAAA repair. High-volume rAAA repair hospitals were associated with a 27% decreased in in-hospital mortality, independent of transfer status or patient rurality. These data underscore the importance of considering rAAA repair at high-volume repair hospitals for patients stable enough to survive rapid transport.