Study Suggests Substantial Variation in Cardiovascular Mortality Rates across the VA Healthcare System
BACKGROUND:
Ischemic heart disease (IHD) and chronic heart failure (CHF) are highly prevalent among VA patients. VA strives to measure and improve the quality of care for Veterans with these conditions, but most of these efforts focus on either process measures of quality (e.g., beta-blockers for heart failure) or surrogate clinical outcomes (e.g., hypertension treatment targets). Very limited data are available on clinical outcomes, and many outcome measures are restricted to Veterans hospitalized with acute cardiovascular events such as myocardial infarction or CHF exacerbations. This retrospective cohort study sought to determine whether there are substantial differences in cardiovascular outcomes across 138 VA medical centers. Specifically, investigators examined risk-standardized mortality rates among patients with IHD (n=930,079) and/or CHF (n=348,015) across the VA healthcare system from 4/1/10 to 9/30/14. Investigators also assessed patient demographics, medical/surgical events (i.e., pneumonia, stroke, coronary revascularization), and comorbidities (i.e., cerebrovascular disease, dementia, dialysis – and for the CHF cohort only, ischemic heart disease).
FINDINGS:
- There is substantial variation in risk-standardized cardiovascular mortality rates across the VA healthcare system, suggesting differences in the quality of cardiovascular healthcare.
- IHD annual death rates at the VAMC with the highest mortality were 3.9 percentage points larger than at the VAMC with the lowest mortality, translating into 1 excess death per year on average among every 26 IHD patients at the highest-mortality VAMC. Similarly, CHF annual death rates were 7.8 percentage points larger, translating into1 excess death per year among every 13 CHF patients at the highest-mortality VAMC compared with CHF patients at the lowest mortality VAMC.
- Twenty-nine VAMCs had IHD mortality rates that significantly exceeded the national mean, while 35 VAMCs had CHF mortality rates that significantly exceeded the national mean.
- Cardiovascular mortality in VA medical centers' chronic cardiovascular disease populations was only modestly correlated with post-hospitalization 30-day outcomes – or with VA's 5-star quality ratings system (each VAMC is annually assessed for overall quality on a 1-5 star scale).
LIMITATIONS:
- Administrative data imperfectly measure comorbidity and do not measure disease severity.
- Variation in coding practices for IHD/CHF across VAMCs may have influenced the size of the patient denominators at each VA medical center; for example, if Veterans with mild disease were more frequently recorded as having IHD and/or CHF in some VAMCs, those VAMCs' mortality rates would have necessarily been lower than VAMCs that were less "aggressive" about coding.
AUTHOR/FUNDING INFORMATION:
This study was funded by HSR&D (IIR 14-077). Dr. Groeneveld and Mss. Medvedeva and Walker are part of HSR&D's Center for Health Equity Research & Promotion (CHERP), in Philadelphia, PA.
Groeneveld P, Medvedeva E, Walker L, et al. Outcomes of Care for Ischemic Coronary Disease and Chronic Heart Failure in the Veterans Health Administration. JAMA Cardiology. July 1, 2018;3(7):563-71.
