Supplementary Material for: Two Decades of Stroke in the United States: A Healthcare Economic Perspective

Background:
Stroke is a leading cause of morbidity and mortality in the United States and has implications on the financial health of patients, families, and healthcare systems.

Objective:
This study aims to determine the economic perspective of stroke on the national healthcare system for the past two decades.

Methods:
This retrospective study of inpatient subjects from 2000 to 2020 with stroke was collected from the Healthcare Cost and Utilization Project (HCUP). We queried patients admitted primarily for ischemic or hemorrhagic stroke. Patients were evaluated for demographics, length of stay (LOS), mortality, and hospital charges. Statistical Z-testing with a significance of p<0.05 was conducted for the analysis.

Results:
During the study period, 12,158,747 stroke subjects were studied, with 51.9% female and a mean age of 70.08 (±0.16) years old. The mean rate of stroke discharges per 100,000 persons was 187.71 (±3.44), decreasing from 200 to 193 during the study (p=0.16). The mean percentage of deaths was 8.78% (±0.17), which decreased from 10.96% to 6.81% (p=0.00). The mean LOS was 6.28 days (±0.08), increased from 6.70 to 7.15 (p=0.00). During the study period, the aggregated national bill was $725 billion. The mean hospital charges-per-patient were $57,178 (±1,504), increasing from $19,647 to $121,765 per person during the study period (p=0.00), while mean hospital costs-per-stay were $15,781 (±330). These data closely conform to an exponential growth pattern, and forecasting per-patient charges for the next ten years demonstrates a cost of $287,836 by 2030.

Conclusions:
Our data show that the rate and mortality of stroke have decreased, but its charges and costs are increasing. The improvement in outcomes could be multifactorial such as establishment of comprehensive stroke centers and evolving treatment modalities. Ironically, the charges-per-patient increased more than sixfold with a national bill almost equal to the annual Medicare budget. Thus, the significance of preventive medicine, such as controlling hypertension, diabetes, and smoking cessation, cannot be understated. With such a dramatically increasing financial burden, improvements in mitigating risk factors, educational programs, and access to care may be a more cost-effective option.

研究背景：
脑卒中（Stroke）是美国范围内导致发病与死亡的主要病因之一，同时对患者、家属及医疗体系的财务健康状况造成显著影响。

研究目标：
本研究旨在从经济学视角，分析过去二十年间脑卒中对全国医疗体系产生的影响。

研究方法：
本研究为回顾性研究，数据提取自医疗成本与利用项目（Healthcare Cost and Utilization Project, HCUP），纳入2000年至2020年期间确诊脑卒中的住院患者。本研究筛选以缺血性脑卒中或出血性脑卒中为主要入院诊断的患者，对其人口统计学特征、住院时长（Length of Stay, LOS）、病死率及住院收费情况进行分析。本研究采用Z检验开展统计学分析，检验显著性阈值设置为P<0.05。

研究结果：
本研究共纳入12,158,747名脑卒中受试者，其中女性占比51.9%，平均年龄为70.08±0.16岁。每10万人中脑卒中出院病例的平均发生率为187.71±3.44，研究期间该数值从200下降至193（P=0.16）。平均病死率为8.78%±0.17，较研究初期的10.96%下降至末期的6.81%（P=0.00）。平均住院时长为6.28±0.08天，较研究初期的6.70天上升至末期的7.15天（P=0.00）。研究期间全国总医疗账单规模达7250亿美元。患者平均住院收费为57,178±1,504美元，研究期间该数值从19,647美元/人增长至121,765美元/人（P=0.00）；而每次住院的平均医院成本为15,781±330美元。上述数据均符合指数增长趋势，对未来十年的患者住院收费进行预测显示，至2030年人均住院收费将达到287,836美元。

研究结论：
本研究数据显示，脑卒中的发生率与病死率均有所下降，但相关收费与成本却呈上升趋势。临床结局的改善可能是多因素共同作用的结果，例如综合脑卒中中心的建立以及治疗手段的迭代更新。值得注意的是，患者人均住院收费增长超过六倍，全国总医疗账单规模几乎等同于美国联邦医疗保险（Medicare）的年度预算。因此，控制高血压、糖尿病及戒烟等预防医学措施的重要性不容小觑。面对日益加剧的财政负担，通过优化风险因素管控、开展健康宣教以及提升医疗服务可及性等方式，或可成为更具成本效益的解决方案。