Supplementary Material for: Gender Disparity of Automatic Implantable Cardioverter Defibrillator Placement for Primary Prevention: National Inpatient Sample Analysis

Introduction

Automatic Implantable Cardioverter-Defibrillators (AICD) for the primary prevention of sudden cardiac death (SCD) have become standard care for patients with systolic heart failure (sHF) and ejection fraction < 35%. While the prevalence of sHF and rates of hospitalization are higher in men; one would expect equivalent rates of implantation in women.

Methods

We used the Healthcare Cost and Utilization Project’s National Inpatient Sample (NIS) from 2009-2018 to identify patient visits with sHF and AICD implantation. The co-morbidities and outcomes were compared based on gender.

Results

There were 15,247,854 inpatient admissions for sHF, of which 60.3% males, (95% CI 60.1%-60.4%) and 39.8% females (95% CI 39.7%-39.9%). Approximately 2% of patients (294,726) underwent the insertion of an AICD for primary prevention; 72.3% males (95% CI 71.9%-72.7%) and 27.72% females (95% CI 27.3%-28.1%). There was no significant difference in age (p=0.29), length of Stay (LOS) (p=0.09) and inpatient mortality (p=0.18).

Conclusion

In this study, women accounted for approximately 40% of patients admitted with the diagnosis of sHF, however, they accounted for less than 30% of patients who underwent the insertion of an AICD. Further research is needed to better understand this gender disparity and identify reasons for the lower rates of AICD placement in women.

## 引言

用于心搏骤停性猝死（sudden cardiac death, SCD）一级预防的自动植入式心脏复律除颤器（Automatic Implantable Cardioverter-Defibrillators, AICD），现已成为射血分数＜35%的收缩性心力衰竭（systolic heart failure, sHF）患者的标准治疗方案。尽管男性群体的收缩性心力衰竭患病率与住院率均高于女性，但理论上两类人群的植入率应当相当。

## 方法

本研究采用2009-2018年美国医疗成本与利用项目（Healthcare Cost and Utilization Project）的全国住院患者样本（National Inpatient Sample, NIS），筛选确诊收缩性心力衰竭并接受自动植入式心脏复律除颤器植入的住院患者，并基于性别对比其合并症与临床结局。

## 结果

本次研究共纳入15,247,854例收缩性心力衰竭住院患者，其中男性占60.3%（95%置信区间：60.1%~60.4%），女性占39.8%（95%置信区间：39.7%~39.9%）。约2%的患者（294,726例）因一级预防接受了自动植入式心脏复律除颤器植入，其中男性占72.3%（95%置信区间：71.9%~72.7%），女性占27.72%（95%置信区间：27.3%~28.1%）；患者的年龄（p=0.29）、住院时长（length of Stay, LOS）（p=0.09）与住院死亡率（p=0.18）均无显著组间差异。

## 结论

本研究显示，尽管收缩性心力衰竭住院患者中女性占比约为40%，但接受自动植入式心脏复律除颤器植入的患者中女性占比不足30%。未来需开展进一步研究以明确此类性别差异的成因，并探究女性自动植入式心脏复律除颤器植入率偏低的根本原因。