Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut2Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, Connecticut.
Yale College, New Haven, Connecticut.
JAMA Cardiol. 2016 Jun 1;1(3):255-65. doi: 10.1001/jamacardio.2016.0382.
During the past decade, the incidence and mortality associated with acute myocardial infarction (AMI) in the United States have decreased substantially. However, it is unknown whether these improvements were consistent across communities of different economic status and geographic regions since efforts to improve cardiovascular disease prevention and management may have had variable impact.
To determine whether trends in US county-level, risk-standardized AMI hospitalization and mortality rates varied by county-based median income level.
DESIGN, SETTING, AND PARTICIPANTS: In this observational study, county-level risk-standardized (age, sex, and race) hospitalization and 1-year mortality rates for AMI from January 1, 1999, to December 31, 2013, were measured for Medicare beneficiaries 65 years or older. Data analysis was performed from June 2 through December 1, 2015. Counties were stratified by median income percentile using 1999 US Census Bureau data adjusted for inflation: low- (<25th), average- (25th-75th), or high- (>75th) income groups.
The effect of income on the slope of AMI hospitalizations and mortality, measured as differences in the rate of change in AMI hospitalizations and mortality by county income and by the 4 US geographic regions, and a possible lag effect among low-income counties.
In the 15-year study period, AMI risk-standardized hospitalization and mortality rates decreased significantly for all 3 county income groups. Mean hospitalization rates were significantly higher among low-income counties compared with high-income counties in 1999 (1353 vs 1123 per 100 000 person-years, respectively) and in 2013 (853 vs 648 per 100 000 person-years, respectively). One-year mortality rates after hospitalization for AMI were similar across county income groups, decreasing from 1999 (31.5%, 31.4%, and 31.1%, for high-, average-, and low-income counties, respectively) to 2013 (26.2%, 26.1%, and 25.4%, respectively). Income was associated with county-level, risk-standardized AMI hospitalization rates but not mortality rates. Increasing 1 interquartile range of median county consumer price index-adjusted income ($12 000) was associated with a decline in 46 and 37 hospitalizations per 100 000 person-years for 1999 and 2013, respectively; interaction between income and time was 0.56. The rate of decline in AMI hospitalizations was similar for all county income groups; however, low-income counties lagged behind high-income counties by 4.3 (95% CI, 3.1-5.9) years. There were no significant differences in trends across geographic regions.
Hospitalization and mortality rates of AMI declined among counties of all income levels, although hospitalization rates among low-income counties lag behind those of the higher income groups. These findings lend support for a more targeted, community-based approach to AMI prevention.
在过去的十年中，美国急性心肌梗死（AMI）的发病率和死亡率大幅下降。然而，由于改善心血管疾病预防和管理的努力可能产生了不同的影响，因此尚不清楚这些改善是否在不同经济地位和地理位置的社区中一致。
确定美国县级风险标准化 AMI 住院和死亡率趋势是否因县为基础的中位收入水平而异。
设计、设置和参与者：在这项观察性研究中，从 1999 年 1 月 1 日至 2013 年 12 月 31 日，对 Medicare 受益人的年龄、性别和种族风险标准化（年龄、性别和种族）AMI 住院和 1 年死亡率进行了测量。数据分析于 2015 年 6 月 2 日至 12 月 1 日进行。根据 1999 年美国人口普查局的数据，将县分为中值收入百分位，数据经通胀调整：低（<25%）、中（25%-75%）或高（>75%）收入群体。
收入对 AMI 住院和死亡率斜率的影响，衡量为县收入和美国 4 个地理区域变化率的差异，以及低收入县之间可能存在的滞后效应。
在 15 年的研究期间，所有 3 个县收入组的 AMI 风险标准化住院和死亡率均显著下降。与高收入县相比，低收入县的住院率在 1999 年（分别为 1353 与 1123 人/每 100000 人年）和 2013 年（分别为 853 与 648 人/每 100000 人年）显著更高。AMI 住院后 1 年死亡率在县收入组之间相似，从 1999 年（分别为 31.5%、31.4%和 31.1%）下降到 2013 年（分别为 26.2%、26.1%和 25.4%）。收入与县级风险标准化 AMI 住院率相关，但与死亡率无关。中值县消费者物价指数调整后收入每增加 1 个四分位距（$12000），分别与 1999 年和 2013 年每 100000 人年下降 46 和 37 例住院率相关；收入与时间之间的交互作用为 0.56。AMI 住院率的下降趋势在所有县收入组中相似；然而，低收入县比高收入县滞后 4.3 年（95%CI，3.1-5.9）。在地理区域之间没有发现趋势的显著差异。
AMI 住院和死亡率在所有收入水平的县都有所下降，尽管低收入县的住院率仍落后于较高收入群体。这些发现为以社区为基础的更有针对性的 AMI 预防方法提供了支持。
