Department of Social Medicine, Toho University, Ota-ku, Tokyo, Japan.
School of Nursing, Shanghai Jiao Tong University, Shanghai, China.
PeerJ. 2022 May 18;10:e13424. doi: 10.7717/peerj.13424. eCollection 2022.
Ischemic heart disease (IHD) is one of the leading causes of mortality worldwide and imposes a heavy burden on patients. Previous studies have indicated that the optimal care for IHD during hospitalisation may reduce the risk of in-hospital mortality. The standardised mortality ratio (SMR) is an indicator for assessing the risk-adjusted in-hospital mortality ratio based on case-mix. This indicator can crucially identify hospitals that can be changed to improve patient safety and the quality of care. This study aimed to determine the hospital-level characteristics of the SMR for IHD in Japan.
This study was designed as a retrospective observational study using the Japanese administrative claim data from 2012 to 2019. The data of all hospital admissions with a primary diagnosis of IHD (ICD-10, I20-I25) were used. Patients with complete variables data were included in this study. Hospitals with less than 200 IHD inpatients in each 2-year period were excluded. The SMR was defined as the ratio of the observed number of in-hospital deaths to the expected number of in-hospital deaths multiplied by 100.The observed number of in-hospital deaths was the sum of the actual number of in-hospital deaths at that hospital, and the expected number of in-hospital deaths was the sum of the probabilities of in-hospital deaths. Ratios of in-hospital mortality was risk-adjusted using multivariable logistic regression analyses. The c-statistic and Hosmer-Lemeshow test were used to evaluate the predictive accuracy of the logistic models. Changes in SMRs in each consecutive period were assessed using Spearman's correlation coefficient.
A total of 64,831 were admitted patients with IHD in 27 hospitals as complete submission data. The SMRs showed wide variation among hospitals, ranging from 35.4 to 197.6, and analysis models indicated good predictive ability with a c-statistic of 0.93 (95% CI [0.92-0.94]) and Hosmer-Lemeshow test of 0.30. The results of chi-square tests and -tests for all variables to assess the association with in-hospital mortality were < 0.001. In the analysis of trends in each consecutive period, the SMRs showed positive correlations.
This study denoted that the SMRs for IHD could be calculated using Japanese administrative claim data. The SMR for IHD might contribute to the development of more appropriate benchmarking systems for hospitals to improve quality of care.
缺血性心脏病（IHD）是全球范围内导致死亡的主要原因之一，给患者带来了沉重的负担。先前的研究表明，住院期间对 IHD 的最佳治疗可能会降低院内死亡率。标准化死亡率比（SMR）是一种基于病例组合评估风险调整后院内死亡率比的指标。该指标可以关键地识别可以改变以提高患者安全性和护理质量的医院。本研究旨在确定日本 IHD 的医院级别特征的 SMR。
本研究设计为使用 2012 年至 2019 年的日本行政索赔数据进行的回顾性观察研究。使用所有主要诊断为 IHD（ICD-10，I20-I25）的住院患者的数据。本研究纳入了具有完整变量数据的患者。排除每个 2 年期间 IHD 住院患者少于 200 人的医院。SMR 定义为观察到的院内死亡人数与预期的院内死亡人数的比值乘以 100。观察到的院内死亡人数是该医院实际死亡人数的总和，而预期的院内死亡人数是院内死亡概率的总和。使用多变量逻辑回归分析对住院死亡率进行风险调整。使用 C 统计量和 Hosmer-Lemeshow 检验评估逻辑模型的预测准确性。使用 Spearman 相关系数评估每个连续时期 SMR 的变化。
27 家医院共收治了 64831 例 IHD 住院患者，其中有完整的提交数据。SMR 在医院之间差异很大，范围从 35.4 到 197.6，分析模型表明具有良好的预测能力，C 统计量为 0.93（95%CI [0.92-0.94]），Hosmer-Lemeshow 检验为 0.30。所有变量的卡方检验和 t 检验评估与院内死亡率的关联均<0.001。在每个连续时期趋势的分析中，SMR 呈正相关。
本研究表明可以使用日本行政索赔数据计算 IHD 的 SMR。IHD 的 SMR 可能有助于为医院制定更合适的基准系统，以提高护理质量。
