Background

International Classification of Disease (ICD)-10 coding of type 1 myocardial infarction (MI) is used for reimbursement, value-based programs, and clinical research.

Objectives

This study sought to determine whether the introduction of ICD-10 codes for type 2 and types 3-5 MI was associated with changes in hospitalizations for ICD-10 codes now attributed to type 1 MI.

Methods

Using the Nationwide Readmissions Database, we identified patients with ICD-10 codes now attributed to type 1 MI between January 2016 and December 2018. Patients were stratified according to the timing of their event in relation to the introduction of the type 2 and types 3-5 MI codes on October 1, 2017.

Results

There were 2,680,323 hospitalizations for ICD-10 codes now attributed to type 1 MI; after adjustment for seasonality, there was a 13.7% decline in hospitalizations after the introduction of the new subtype codes. Patients with ICD-10 codes now attributed to type 1 MI after the coding change were less likely to be female, had lower prevalence of several cardiovascular and noncardiovascular comorbidities, and had higher rates of coronary angiography and revascularization. After introduction of the new codes, there was a positive deflection in the slope of risk-adjusted in-hospital mortality (0.007%; P <0.001) and a negative deflection in risk-adjusted 30-day readmission (−0.002%; P = 0.05) for patients with ICD-10 codes now attributed to type 1 MI.

Conclusions

The introduction of ICD-10 codes for type 2 and types 3-5 MI was associated with a decrease in hospitalizations for ICD-10 codes now attributed to type 1 MI and changes in the observed characteristics and treatment patterns of these patients.

中文翻译：

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在引入 MI 亚型代码之前和之后观察到的 T1MI 住院和结果

背景

1 型心肌梗死 (MI) 的国际疾病分类 (ICD)-10 编码用于报销、基于价值的计划和临床研究。

目标

本研究试图确定引入 ICD-10 代码用于 2 型和 3-5 型 MI 是否与现在归因于 1 型 MI 的 ICD-10 代码住院变化有关。

方法

使用全国再入院数据库，我们确定了 2016 年 1 月至 2018 年 12 月期间具有 ICD-10 代码的患者，现在归因于 1 型 MI。根据与引入 2 型和 3 型相关的事件发生时间对患者进行分层 - 2017 年 10 月 1 日的 5 个 MI 代码。

结果

有 2,680,323 人因 ICD-10 代码住院治疗，现在归因于 1 型心梗；在进行季节性调整后，在引入新的亚型代码后，住院人数下降了 13.7%。编码更改后将 ICD-10 编码归为 1 型 MI 的患者不太可能是女性，几种心血管和非心血管合并症的患病率较低，冠状动脉造影和血运重建率较高。引入新代码后，风险调整后的住院死亡率斜率呈正偏差（0.007%；P  <0.001），风险调整后的 30 天再入院率呈负偏差（-0.002%；P  = 0.05) 对于 ICD-10 代码现在归因于 1 型 MI 的患者。

结论

针对 2 型和 3-5 型 MI 的 ICD-10 代码的引入与现在归因于 1 型 MI 的 ICD-10 代码住院减少以及这些患者观察到的特征和治疗模式的变化有关。