Institute of Nursing Science (INS), Department Public Health (DPH), Faculty of Medicine, University of Basel, Basel, Switzerland.
Patient Safety Office, University Hospital Basel, Basel, Switzerland.
BMC Health Serv Res. 2021 Jan 6;21(1):13. doi: 10.1186/s12913-020-05999-5.
Understanding how comorbidity measures contribute to patient mortality is essential both to describe patient health status and to adjust for risks and potential confounding. The Charlson and Elixhauser comorbidity indices are well-established for risk adjustment and mortality prediction. Still, a different set of comorbidity weights might improve the prediction of in-hospital mortality. The present study, therefore, aimed to derive a set of new Swiss Elixhauser comorbidity weightings, to validate and compare them against those of the Charlson and Elixhauser-based van Walraven weights in an adult in-patient population-based cohort of general hospitals.
Retrospective analysis was conducted with routine data of 102 Swiss general hospitals (2012-2017) for 6.09 million inpatient cases. To derive the Swiss weightings for the Elixhauser comorbidity index, we randomly halved the inpatient data and validated the results of part 1 alongside the established weighting systems in part 2, to predict in-hospital mortality. Charlson and van Walraven weights were applied to Charlson and Elixhauser comorbidity indices. Derivation and validation of weightings were conducted with generalized additive models adjusted for age, gender and hospital types.
Overall, the Elixhauser indices, c-statistic with Swiss weights (0.867, 95% CI, 0.865-0.868) and van Walraven's weights (0.863, 95% CI, 0.862-0.864) had substantial advantage over Charlson's weights (0.850, 95% CI, 0.849-0.851) and in the derivation and validation groups. The net reclassification improvement of new Swiss weights improved the predictive performance by 1.6% on the Elixhauser-van Walraven and 4.9% on the Charlson weights.
All weightings confirmed previous results with the national dataset. The new Swiss weightings model improved slightly the prediction of in-hospital mortality in Swiss hospitals. The newly derive weights support patient population-based analysis of in-hospital mortality and seek country or specific cohort-based weightings.
了解合并症指标如何影响患者死亡率对于描述患者健康状况以及调整风险和潜在混杂因素至关重要。Charlson 和 Elixhauser 合并症指数是风险调整和死亡率预测的成熟指标。然而，使用不同的合并症权重可能会提高住院死亡率的预测准确性。因此，本研究旨在为瑞士的 Elixhauser 合并症指数建立一套新的权重，并在瑞士的综合医院成年住院患者队列中验证和比较这些权重与 Charlson 和基于 van Walraven 的 Elixhauser 权重。
本研究采用回顾性分析方法，使用 2012 年至 2017 年瑞士 102 家综合医院的常规数据，对 609 万例住院患者进行分析。为了推导出瑞士的 Elixhauser 合并症指数权重，我们将住院数据随机分成两半，在第 2 部分中同时验证第 1 部分的结果以及已建立的权重系统，以预测住院死亡率。Charlson 和 van Walraven 权重应用于 Charlson 和 Elixhauser 合并症指数。权重的推导和验证使用广义加性模型进行调整，包括年龄、性别和医院类型。
总体而言，Elixhauser 指数的瑞士权重（0.867，95%CI，0.865-0.868）和 van Walraven 的权重（0.863，95%CI，0.862-0.864）与 Charlson 权重（0.850，95%CI，0.849-0.851）相比，在推导和验证组中均具有显著优势。新的瑞士权重的净重新分类改善提高了 Elixhauser-van Walraven 权重的预测性能 1.6%，提高了 Charlson 权重的预测性能 4.9%。
所有权重均证实了基于全国数据集的先前结果。新的瑞士权重模型略微提高了瑞士医院住院死亡率的预测准确性。新的权重支持基于患者人群的住院死亡率分析，并寻求基于国家或特定队列的权重。
