Acknowledging the role of patient heterogeneity in hospital outcome reporting: Mortality after acute myocardial infarction in five European countries

PLoS One. 2020 Feb 6;15(2):e0228425. doi: 10.1371/journal.pone.0228425. eCollection 2020.

Abstract

Background: Hospital performance, presented as the comparison of average measurements, dismisses that hospital outcomes may vary across types of patients. We aim at drawing out the relevance of accounting for patient heterogeneity when reporting on hospital performance.

Methods: An observational study on administrative data from virtually all 2009 hospital admissions for Acute Myocardial Infarction (AMI) discharged in Denmark, Portugal, Slovenia, Spain, and Sweden. Hospital performance was proxied using in-hospital risk-adjusted mortality. Multilevel Regression Modelling (MLRM) was used to assess differences in hospital performance, comparing the estimates of random intercept modelling (capturing hospital general contextual effects (GCE)), and random slope modelling (capturing hospital contextual effects for patients with and without congestive heart failure -CHF). The weighted Kappa Index (KI) was used to assess the agreement between performance estimates.

Results: We analysed 46,875 admissions of AMI, 6,314 with coexistent CHF, discharged from 107 hospitals. The overall in-hospital mortality rate was 5.2%, ranging from 4% in Sweden to 6.9% in Portugal. The MLRM with random slope outperformed the model with only random intercept, highlighting a much higher GCE in CHF patients [VPC = 8.34 (CI95% 4.94 to 13.03) and MOR = 1.69 (CI95% 1.62 to 2.21) vs. VPC = 3.9 (CI95% 2.4 to 5.9), MOR of 1.42 (CI95% 1.31 to 1.54) without CHF]. No agreement was observed between estimates [KI = -0,02 (CI95% -0,08 to 0.04].

Conclusions: The different GCE in AMI patients with and without CHF, along with the lack of agreement in estimates, suggests that accounting for patient heterogeneity is required to adequately characterize and report on hospital performance.

Publication types

  • Multicenter Study
  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Demography
  • Denmark / epidemiology
  • Europe / epidemiology
  • Female
  • Hospital Mortality*
  • Hospitalization / statistics & numerical data*
  • Hospitals, General / statistics & numerical data
  • Humans
  • Male
  • Middle Aged
  • Myocardial Infarction / mortality*
  • Patient Discharge / statistics & numerical data*
  • Portugal / epidemiology
  • Research Design / statistics & numerical data
  • Slovenia / epidemiology
  • Spain / epidemiology
  • Sweden / epidemiology
  • Treatment Outcome

Grants and funding

This study has been funded by the Spanish Institute for Health Carlos III through the project “The Research Network on Health Services Research on Chronic Patients (REDISSEC)", registered grant RD16/0001/0007, and co-funded by European Regional Development Fund “Investing in your future”. On the other hand, the ECHO Project received funding from the 7th Framework Programme of the European Union (2010-2014) with Grant HEALTH-F3-2010-242189 and from the European Union’s Health Programme (2014-2020) with Grant 664691/BRIDGE Health. Additionally, the authors Enrique Bernal-Delgado, Micaela Comendeiro-Maaløe and Francisco Estupiñán-Romero have been partially funded by the Spanish Institute for Health Carlos III through a public competitive grant (RD16/0001/0007) as research members of "The Research Network for Health Services Research on Chronic Patients (REDISSEC)". All these funding sources played no role in the study design, data collection or the analysis, decision to publish, or preparation of the manuscript. There was no additional external funding received for this study.