第一部分 中国心肌病疾病负担及管理能力调研
中文摘要
研究背景
心肌病是一类累及心肌组织、病因复杂多样、临床表现具有高度异质性的疾病。目前，心肌病已在全球范围内构成了相当大的公共卫生负担，可能导致心脏性猝死、心力衰竭和卒中等严重并发症。我国心肌病患者数量庞大，医疗需求高。然而目前我国仍缺乏全国范围内有代表性的研究来评估心肌病疾病负担和各医疗机构对心肌病的管理能力。
研究目的
通过全国范围内多中心研究评估心肌病疾病负担和位于不同地理位置-经济分区的三级医院对心肌病的管理能力。
研究方法
本研究采用多阶段随机抽样的方法抽取参与医院。第一阶段进行三级医院的招募，最终有88家三级医院具备完善的电子病历系统，报名参与研究。第二阶段在每个地理位置-经济分区分层后通过随机抽样的方法共抽取了66家参与医院。收集各参与医院2017年至2021年每年因心肌病就诊的门诊就诊人次和住院人次，同时收集其年龄和性别的分布特征；同时调研各家医院的心肌病管理能力，包括心肌病相关诊断评估、治疗和综合管理方面的能力。
研究制定了一个量表用于评估每家参与医院心肌病管理能力的水平，根据医院是否满足相应的能力要求，将医院分为心肌病综合诊疗中心、心肌病初级诊疗中心或两者皆不是。采用两种医院分组策略：根据参与医院行政级别的不同，分为省级中心和市级中心；根据参与医院所在城市经济水平的不同分为经济发达和经济非发达。以标准化均值差（Standardized mean difference, SMD）来量化各医院心肌病管理能力差异的大小，SMD>0.1视为差异具有统计学意义。
研究结果
66家参与医院总体心肌病门诊人次从2017年的109,112人次增加到2021年的151,262人次，增幅（95%置信区间[Confidence interval, CI]）为38.6%（38.3%-38.9%）；心肌病住院人次从2017年的16,555人次增加到2021年的22,014人次，增幅（95%CI）为33.0%（32.3%-33.7%）。所有参与医院均可行超声心动图、24小时动态心电图、冠状动脉计算机断层扫描血管成像、冠状动脉造影、左心室造影和侵入性心脏电生理检查用于心肌病的初步评估。然而对于市级医院或经济非发达城市的医院，放射性核素显像、心内膜心肌活检和一些复杂的侵入性治疗策略（包括室间隔减容术、左心室辅助装置和心脏移植术）的普及率很低，与省级医院和经济发达城市医院的普及率差异有统计学意义（SMD均>0.1）。根据研究制定的量表，在66家参与医院中只有4家（6.1%）医院满足心肌病综合诊疗中心的标准；29家（43.9%）医院满足心肌病初级诊疗中心的标准。并且，4家满足心肌病综合诊疗中心标准的医院均是位于经济发达城市的省级医院。
研究结论
本研究发现自2017年至2021年，中国心肌病的疾病负担显著增加。虽然我国三级医院已基本普及了心肌病初步评估手段，然而，更高级复杂的诊疗手段仍未得到广泛应用。此外，不同行政级别以及不同经济水平的医院在心肌病管理能力上仍存在发展不平衡的问题。我们希望这些发现对提高心肌病管理质量和优化医疗资源配置有所帮助。
 

第二部分 心肌病住院患者的临床特征、治疗模式和医疗资源使用研究
中文摘要
研究背景
心肌病是一类累及心肌组织、病因复杂多样、临床表现具有高度异质性的疾病。不同类型心肌病的临床表现可能影响治疗选择。前期我们对心肌病诊疗现状调研结果显示，自2017年至2021年中国心肌病的就诊人次显著增加。因此，患者和整个社会可能承担与心肌病管理相关的巨大成本。此外，我国不同行政级别以及不同经济水平的医院在心肌病管理能力上仍存在发展不平衡的问题。在参研的66家三级医院中只有4家医院被评为心肌病综合诊疗中心，中国医学科学院阜外医院为其中之一。评估与心肌病管理相关的医疗资源使用（Healthcare resource utilization, HRU）及其成本驱动因素，对于指导医疗领域优先决策非常重要。然而，我国仍缺乏对几种常见类型心肌病的临床特征、治疗模式和HRU数据。
研究目的
旨在评估作为心肌病综合诊疗中心的中国医学科学院阜外医院住院心肌病患者的临床特征、治疗模式和HRU情况。
研究方法
入选2017年3月至2022年2月在中国医学科学院阜外医院住院的五种最常见类型的心肌病，包括肥厚型心肌病（Hypertrophic cardiomyopathy, HCM）、扩张型心肌病（Dilated cardiomyopathy, DCM）、致心律失常性心肌病（Arrhythmogenic cardiomyopathy, ACM）、限制型心肌病（Restrictive cardiomyopathy, RCM）和左室心肌致密化不全（Left ventricular noncompaction, LVNC）。收集其临床特征、治疗模式、次均总住院费用以及次均住院天数。本研究中次均总住院费用和次均住院天数虽为偏态分布，但在医疗决策中，更关注其均值情况，因此，本研究中对于两者的描述均采用均值描述。次均总住院费用的影响因素分析将入院年份作为固定效应纳入广义线性回归模型，并计算回归系数β和95%置信区间（Confidence interval, CI）。双测p值<0.05为差异具有统计学意义。
研究结果
5年间住院的心肌病患者共3,462人次。不同心肌病患者的年龄、性别、纽约心脏病协会（New York Heart Association, NYHA）心功能分级、左室射血分数（Left ventricular ejection fraction, LVEF）及合并症史均存在显著差异（p均<0.05）。61.5%的患者治疗模式为单纯药物治疗，且不同心肌病类型之间治疗模式存在显著差异（p<0.001）。总体心肌病住院患者的次均住院天数为15.2天，次均总住院费用为76,756.0元。无论心肌病类型如何，耗材类费用在次均总住院费用中占比最高（范围：23.1%–38.4%）。
在探究总体心肌病住院患者次均总住院费用的影响因素上，校正混杂因素后，年龄（β:0.002, 95%CI: 0.001, 0.003, p<0.001）、合并症数量（β:0.007, 95%CI: 0.000, 0.013, p=0.043）、NYHA心功能III/IV级（β: 0.075, 95%CI: 0.035, 0.114, p<0.001）以及LVEF（β:-0.002, 95%CI: -0.004, -0.001, p<0.001）与次均总住院费用显著相关。此外，与HCM住院患者的次均总住院费用相比，DCM（β:1.065, 95%CI: 1.005, 1.125, p<0.001）、ACM（β:1.108, 95%CI: 1.040, 1.174, p<0.001）、RCM（β:1.022, 95%CI: 0.944, 1.097, p<0.001）和LVNC（β:1.108, 95%CI: 1.003, 1.208, p<0.001）住院患者的次均总住院费用更高。与采用药物治疗与介入治疗相结合的患者相比，采用药物治疗与外科手术治疗相结合的患者（β:2.425, 95%CI: 2.363, 2.490 vs. β:1.044, 95%CI: 0.970, 1.120）次均总住院费用更高。
研究结论
本研究展示了作为心肌病综合诊疗中心的中国医学科学院阜外医院2017年至2022年住院心肌病患者的临床特征、治疗模式和HRU的真实世界数据，结果显示，总体心肌病住院患者的次均总住院费用高于同级别委属医院急性心肌梗死和充血性心力衰竭的次均总住院费用。年龄大、合并症数量多、NYHA心功能分级差、LVEF低与心肌病患者次均总住院费用高相关；同时，治疗模式和心肌病类型的不同也会影响次均总住院费用。然而，无论心肌病类型如何，耗材类费用在次均总住院费用中占比均最高，这表明优化医疗耗材的使用可能是降低次均总住院费用的最有效途径。我们的研究结果将为心肌病管理中决策制定提供依据。

Part I
The burden and management competency of cardiomyopathies in China: a nationwide survey study 
Abstract
Background
Cardiomyopathy is a category of diseases that affect the myocardial tissue, characterized by complex and diverse etiologies, and highly heterogeneous clinical manifestations. Cardiomyopathies represent a considerable global health burden, potentially resulting in sudden cardiac death, heart failure and stroke in many cases. The number of cardiomyopathy patients in China is vast, with high medical demands. However, to date, no nationwide studies were conducted to assess the disease burden for cardiomyopathies and evaluate the management competency of cardiomyopathies by health agencies in China.
Objectives 
This nationwide survey-based study was performed to assess the disease burden for cardiomyopathies, and evaluate the management competency of cardiomyopathies by tertiary hospitals in various geographic-economic regions in mainland China. 
Methods
This study adopted a multi-stage sampling method for hospital selection. The first stage involved nationwide tertiary hospitals recruitment, which led to the recruitment of 88 hospitals with the consent of the director of cardiology and the established electronic medical records system. In the second stage, 66 of the 88 hospitals were selected using a random sampling process within each geographic-economic stratification according to the design. Data on (1) the total number of outpatient and inpatient visits for cardiomyopathies (stratified by patient age and sex) for each year between 2017 and 2021, and (2) the hospital-based competency in performing cardiomyopathy-related diagnosis and assessment procedures, treatment, and integrated patient management. 
The competency of a hospital to provide cardiomyopathy care was evaluated using a specifically devised scale. A hospital was then considered to be a comprehensive cardiomyopathy center, a primary cardiomyopathy center, or neither, based on whether it met the corresponding competency requirements. Two hospital grouping strategies were used to assess how competently the cardiomyopathies were managed by the various participating hospitals: (1) provincial and municipal, according to the administrative level of a participating hospital; and (2) economically developed and undeveloped, according to the economic status of the city where the participating hospital was located. The standardized mean difference (SMD) was used to quantify the magnitude of differences in management competency of cardiomyopathies among hospitals, with a SMD>0.1 considered statistically significant.
Results
Overall, the outpatient visits increased from 109,112 in 2017 to 151,262 in 2021, which corresponded to a 38.6% increase (95% confidence interval [CI] 38.3%-38.9%]). Meanwhile, the inpatient visits increased from 16,555 in 2017 to 22,014 in 2021, which corresponded to a 33.0% increase (95%CI 32.3%-33.7%). Echocardiography, holter electrocardiography, coronary computed tomography angiography, coronary angiography, left heart ventricular angiography, and invasive cardiac electrophysiology were available for cardiomyopathy assessment in all hospitals. However, the provision of nuclear imaging, endomyocardial biopsy, and some advanced treatments (e.g., septal reduction therapy, left ventricular assist device implantation, and heart transplantation) was very low in municipal hospitals and hospitals in economically undeveloped cities, which is significantly lower than that in provincial hospitals and hospitals in economically developed cities (both SMD >0.1). Only 4 (6.1%) of the 66 participating hospitals met the criteria for being designated as a comprehensive cardiomyopathy center, and only 29 (43.9%) could be classified as a primary cardiomyopathy center. Of note, all four of the comprehensive cardiomyopathy centers were provincial hospitals located in economically developed cities. 
Conclusion
The health burden of cardiomyopathies has increased significantly between 2017 and 2021 in China. Although most tertiary hospitals in China can offer basic cardiomyopathy care, more advanced facilities are not yet universally available. Moreover, there remains an issue of inconsistencies in the management of cardiomyopathies across hospitals due to differing administrative and economic levels. We envisage that our findings will help guide future work to improve the care of patients with cardiomyopathies and the nation allocation of medical resources.
 

Part II

Clinical characteristics, treatment patterns, and healthcare resource utilization among hospitalized patients with cardiomyopathy

Abstract

Background

Cardiomyopathy is a category of diseases that affect the myocardial tissue, characterized by complex and diverse etiologies, and highly heterogeneous clinical manifestations. Differences in clinical presentation among subtypes of cardiomyopathy can influence the choice of treatment. Our study found that the number of visits for cardiomyopathies rapidly increased from 2017 to 2021 in China. Consequently, patients and society as a whole are likely to incur significant costs associated with disease management. Moreover, there remains an issue of inconsistencies in the management of cardiomyopathies across hospitals due to differing administrative and economic levels. Only 4 of the 66 participating hospitals met the criteria for being designated as a comprehensive cardiomyopathy center, with Fuwai Hospital of Chinese Academy of Medical Sciences being one of them. Evaluating the healthcare resource utilization (HRU) associated with cardiomyopathy management, along with its specific cost drivers, is important to guide prioritisation decisions within healthcare policy. However, little is known about clinical characteristics, treatment patterns, and HRU in several common cardiomyopathies in China.

Objectives 

The aim of this study was to assess the clinical characteristics, treatment patterns, and HRU among hospitalized patients with cardiomyopathy in Fuwai Hospital as the comprehensive cardiomyopathy center.

Methods

Inpatient admissions with one of five major cardiomyopathy subtypes were eligible for inclusion in the study: hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), arrhythmogenic cardiomyopathy (ACM), restrictive cardiomyopathy (RCM), and left ventricular noncompaction (LVNC) from March 2017 to February 2022 in Fuwai Hospital. Available data included clinical characteristics, treatment patterns, total cost per hospital admission, and total length of stay per admission. In this study, although the total cost per admission and the length of stay per admission were skewed in distribution, the mean values were of greater interest for medical decision-making. Therefore, both of them were described using mean values in this study. Additionally, the total cost per admission was analysed using a generalized linear regression model with the admission year as a fixed effect, and the regression coefficient β and 95% confidence interval (CI) were calculated. A 2-sided p value<0.05 indicated statistical significance.

Results

We collected a total of 3,462 medical records for adult inpatients with cardiomyopathy. Among cardiomyopathy subtypes, we observed significant differences in age, sex, New York Heart Association class (NYHA), left ventricular ejection fraction (LVEF), and history of medical comorbidities (p<0.05). The treatment pattern for most patients was medical therapy alone (61.5%), with significant differences among cardiomyopathy subtypes (p<0.001). The mean length of stay of all admissions was at 15.2 days, while total costs per admission averaged $11,405.1. Regardless of cardiomyopathy subtype, medical consumables accounted for the highest proportion of total hospitalized costs (range: 23.1%–38.4%).

Age (β: 0.002, 95% CI: 0.001, 0.003, p<0.001), number of medical comorbidities (β: 0.007, 95% CI: 0.000, 0.013, p=0.043), NYHA III/IV (β: 0.075, 95% CI: 0.035, 0.114, p<0.001), and LVEF (β: -0.002, 95% CI: -0.004, -0.001, p<0.001) were significantly associated with total cost of hospitalization after adjusting for confounding variables in generalized linear regression analysis. Compared with admissions with HCM, admissions with DCM (β: 1.065, 95% CI: 1.005, 1.125, p<0.001), ACM (β: 1.108, 95% CI: 1.040, 1.174, p<0.001), RCM (β: 1.022, 95% CI: 0.944, 1.097, p<0.001) or LVNC (β: 1.108, 95% CI: 1.003, 1.208, p<0.001) had higher total costs after multivariate adjustment. Compared with patients treated with a combination of medical therapy and interventional procedures, those treated with a combination of medical therapy and surgery (β: 2.425, 95% CI: 2.363, 2.490 vs. β: 1.044, 95% CI: 0.970, 1.120) had higher total costs after multivariate adjustment.

Conclusion

Our study revealed clinical characteristics, treatment patterns, and HRU of hospitalized patients with cardiomyopathy from 2017 to 2022 in Fuwai Hospital as the comprehensive cardiomyopathy center. The results showed that the average total cost per admission for cardiomyopathy patients was higher than that for acute myocardial infarction and congestive heart failure patients in hospitals of the same level. Older age, a higher number of comorbidities, worse NYHA class, and lower LVEF were associated with higher average total costs per admission for cardiomyopathy patients. Various treatment patterns and cardiomyopathy subtypes had an impact on total cost of hospitalization. However, medical consumables accounted for the greatest proportion of costs, regardless of cardiomyopathy subtype, indicating that optimizing the use of medical consumables may be the most effective approach to reducing total cost of hospitalization. Our findings will help guide prioritisation decisions within healthcare policy in cardiomyopathy management.