[Minimum Caseload Requirements and In-hospital Mortality: Observational Study using Nationwide Hospital Discharge Data from 2006 to 2013].

Background

In order to improve hospital care, minimum caseload requirements for certain elective hospital treatments have been defined by law in Germany. This study analyses retrospectively if adherence to this regulation is associated with the outcome of hospital treatment. Differences in in-hospital mortality were analyzed for complex esophageal and pancreatic surgery, liver and kidney transplantation, stem cell transplantation and total knee replacement.

Methods

Within individual inpatient data of the nationwide German hospital discharge data (DRG statistics) all inpatient episodes subject to the minimum volume requirements were identified and annual caseloads per hospital were calculated. Inpatient episodes were assigned to 2 groups: Patients treated in hospitals with a caseload equal to or greater than the minimum caseload (≥ MC) and patients treated in hospitals with a caseload below the minimum caseload (< MC). Logistic regression was used to calculate adjusted in-hospital mortality.

Results

In total, 28 931 esophageal surgeries, 78 879 pancreatic surgeries, 7 984 liver transplantations, 21 773 kidney transplantations, 51 064 stem cell transplantations and 1 093 296 total knee replacements were analyzed. Adjusted in-hospital mortality in hospitals with a caseload≥MC was significantly lower than in hospitals with a caseload<MC for esophageal surgery (9.2% [95% KI 8.8-9,6] vs. 12.1% [11.4-12.9]), pancreatic surgery (8.6% [8.3-8.8] vs. 11.8% [11.2-12.5]), kidney transplantation (1.7% [1.4-1.8] vs. 3.3% [2.1-5.0]) and total knee replacement (0.13% [0.12-0.14] vs. 0.18% [0.14-0.23]). For liver transplantation, no significant difference in adjusted mortality was found (15.5% [14.7-16.5] vs. 15.9% [12.9-19.3]). For stem cell transplantation mortality in hospitals with a caseload≥MC was significantly higher than in hospital with a caseload<MC (6.0% [5.7-6.2] vs. 4.0% [3.2-4.9]).

Conclusion

For 4 of the 6 studied treatments, a significantly lower risk of in-hospital death was observed in hospitals that adhere to the minimum caseload requirement. This implies that, for those treatments, full implementation of the minimum caseload regulation could improve the quality of hospital care in Germany.