Publications

2024

Kazi, Dhruv S, Mitchell S Elkind V, Anne Deutsch, William N Dowd, Paul Heidenreich, Olga Khavjou, Daniel Mark, et al. (2024) 2024. “Forecasting the Economic Burden of Cardiovascular Disease and Stroke in the United States Through 2050: A Presidential Advisory From the American Heart Association.”. Circulation 150 (4): e89-e101. https://doi.org/10.1161/CIR.0000000000001258.

BACKGROUND: Quantifying the economic burden of cardiovascular disease and stroke over the coming decades may inform policy, health system, and community-level interventions for prevention and treatment.

METHODS: We used nationally representative health, economic, and demographic data to project health care costs attributable to key cardiovascular risk factors (hypertension, diabetes, hypercholesterolemia) and conditions (coronary heart disease, stroke, heart failure, atrial fibrillation) through 2050. The human capital approach was used to estimate productivity losses from morbidity and premature mortality due to cardiovascular conditions.

RESULTS: One in 3 US adults received care for a cardiovascular risk factor or condition in 2020. Annual inflation-adjusted (2022 US dollars) health care costs of cardiovascular risk factors are projected to triple between 2020 and 2050, from $400 billion to $1344 billion. For cardiovascular conditions, annual health care costs are projected to almost quadruple, from $393 billion to $1490 billion, and productivity losses are projected to increase by 54%, from $234 billion to $361 billion. Stroke is projected to account for the largest absolute increase in costs. Large relative increases among the Asian American population (497%) and Hispanic American population (489%) reflect the projected increases in the size of these populations.

CONCLUSIONS: The economic burden of cardiovascular risk factors and overt cardiovascular disease in the United States is projected to increase substantially in the coming decades. Development and deployment of cost-effective programs and policies to promote cardiovascular health are urgently needed to rein in costs and to equitably enhance population health.

Diao, James A, Ivy Shi, Venkatesh L Murthy, Thomas A Buckley, Chirag J Patel, Emma Pierson, Robert W Yeh, Dhruv S Kazi, Rishi K Wadhera, and Arjun K Manrai. (2024) 2024. “Projected Changes in Statin and Antihypertensive Therapy Eligibility With the AHA PREVENT Cardiovascular Risk Equations.”. JAMA 332 (12): 989-1000. https://doi.org/10.1001/jama.2024.12537.

IMPORTANCE: Since 2013, the American College of Cardiology (ACC) and American Heart Association (AHA) have recommended the pooled cohort equations (PCEs) for estimating the 10-year risk of atherosclerotic cardiovascular disease (ASCVD). An AHA scientific advisory group recently developed the Predicting Risk of cardiovascular disease EVENTs (PREVENT) equations, which incorporated kidney measures, removed race as an input, and improved calibration in contemporary populations. PREVENT is known to produce ASCVD risk predictions that are lower than those produced by the PCEs, but the potential clinical implications have not been quantified.

OBJECTIVE: To estimate the number of US adults who would experience changes in risk categorization, treatment eligibility, or clinical outcomes when applying PREVENT equations to existing ACC and AHA guidelines.

DESIGN, SETTING, AND PARTICIPANTS: Nationally representative cross-sectional sample of 7765 US adults aged 30 to 79 years who participated in the National Health and Nutrition Examination Surveys of 2011 to March 2020, which had response rates ranging from 47% to 70%.

MAIN OUTCOMES AND MEASURES: Differences in predicted 10-year ASCVD risk, ACC and AHA risk categorization, eligibility for statin or antihypertensive therapy, and projected occurrences of myocardial infarction or stroke.

RESULTS: In a nationally representative sample of 7765 US adults aged 30 to 79 years (median age, 53 years; 51.3% women), it was estimated that using PREVENT equations would reclassify approximately half of US adults to lower ACC and AHA risk categories (53.0% [95% CI, 51.2%-54.8%]) and very few US adults to higher risk categories (0.41% [95% CI, 0.25%-0.62%]). The number of US adults receiving or recommended for preventive treatment would decrease by an estimated 14.3 million (95% CI, 12.6 million-15.9 million) for statin therapy and 2.62 million (95% CI, 2.02 million-3.21 million) for antihypertensive therapy. The study estimated that, over 10 years, these decreases in treatment eligibility could result in 107 000 additional occurrences of myocardial infarction or stroke. Eligibility changes would affect twice as many men as women and a greater proportion of Black adults than White adults.

CONCLUSION AND RELEVANCE: By assigning lower ASCVD risk predictions, application of the PREVENT equations to existing treatment thresholds could reduce eligibility for statin and antihypertensive therapy among 15.8 million US adults.

Kazi, Dhruv S, Ethan Katznelson, Chia-Liang Liu, Nora M Al-Roub, Richard S Chaudhary, Diane E Young, Megan McNichol, et al. (2024) 2024. “Climate Change and Cardiovascular Health: A Systematic Review.”. JAMA Cardiology 9 (8): 748-57. https://doi.org/10.1001/jamacardio.2024.1321.

IMPORTANCE: Climate change may increase the risk of adverse cardiovascular outcomes by causing direct physiologic changes, psychological distress, and disruption of health-related infrastructure. Yet, the association between numerous climate change-related environmental stressors and the incidence of adverse cardiovascular events has not been systematically reviewed.

OBJECTIVE: To review the current evidence on the association between climate change-related environmental stressors and adverse cardiovascular outcomes.

EVIDENCE REVIEW: PubMed, Embase, Web of Science, and Cochrane Library were searched to identify peer-reviewed publications from January 1, 1970, through November 15, 2023, that evaluated associations between environmental exposures and cardiovascular mortality, acute cardiovascular events, and related health care utilization. Studies that examined only nonwildfire-sourced particulate air pollution were excluded. Two investigators independently screened 20 798 articles and selected 2564 for full-text review. Study quality was assessed using the Navigation Guide framework. Findings were qualitatively synthesized as substantial differences in study design precluded quantitative meta-analysis.

FINDINGS: Of 492 observational studies that met inclusion criteria, 182 examined extreme temperature, 210 ground-level ozone, 45 wildfire smoke, and 63 extreme weather events, such as hurricanes, dust storms, and droughts. These studies presented findings from 30 high-income countries, 17 middle-income countries, and 1 low-income country. The strength of evidence was rated as sufficient for extreme temperature; ground-level ozone; tropical storms, hurricanes, and cyclones; and dust storms. Evidence was limited for wildfire smoke and inadequate for drought and mudslides. Exposure to extreme temperature was associated with increased cardiovascular mortality and morbidity, but the magnitude varied with temperature and duration of exposure. Ground-level ozone amplified the risk associated with higher temperatures and vice versa. Extreme weather events, such as hurricanes, were associated with increased cardiovascular risk that persisted for many months after the initial event. Some studies noted a small increase in cardiovascular mortality, out-of-hospital cardiac arrests, and hospitalizations for ischemic heart disease after exposure to wildfire smoke, while others found no association. Older adults, racial and ethnic minoritized populations, and lower-wealth communities were disproportionately affected.

CONCLUSIONS AND RELEVANCE: Several environmental stressors that are predicted to increase in frequency and intensity with climate change are associated with increased cardiovascular risk, but data on outcomes in low-income countries are lacking. Urgent action is needed to mitigate climate change-associated cardiovascular risk, particularly in vulnerable populations.

Sims, Kendra D, Pengxiao Carol Wei, Joanne M Penko, Susan Hennessy, Pamela G Coxson, Nita H Mukand, Brandon K Bellows, et al. (2024) 2024. “Projected Impact of Nonpharmacologic Management of Stage 1 Hypertension Among Lower-Risk US Adults.”. Hypertension (Dallas, Tex. : 1979) 81 (8): 1758-65. https://doi.org/10.1161/HYPERTENSIONAHA.124.22704.

BACKGROUND: The 2017 American College of Cardiology/American Heart Association blood pressure guideline classified 31 million US adults as having stage 1 hypertension and recommended clinicians provide counseling on behavioral change to the low-risk portion of this group. However, nationwide reductions in cardiovascular disease (CVD) and associated health care expenditures achievable by nonpharmacologic therapy remain unquantified.

METHODS: We simulated interventions on a target population of US adults aged 35 to 64 years, identified from the 2015-2018 National Health and Nutrition Examination Survey, with low-risk stage 1 systolic hypertension: that is, untreated systolic blood pressure 130 to 139 mm Hg with diastolic BP <90 mm Hg; no history of CVD, diabetes, or chronic kidney disease; and a low 10-year risk of CVD. We used meta-analyses and trials to estimate the effects of population-level behavior modification on systolic blood pressure. We assessed the extent to which restricting intervention to those in regular contact with clinicians might prevent the delivery of nonpharmacologic therapy.

RESULTS: Controlling systolic blood pressure to <130 mm Hg among the 8.8 million low-risk US adults with stage 1 hypertension could prevent 26 100 CVD events, avoid 2900 deaths, and save $1.7 billion in total direct health care costs over 10 years. Adoption of the Dietary Approaches to Stop Hypertension diet could prevent 28 000 CVD events. Other nonpharmacologic interventions could avert between 3800 and 19 500 CVD events. However, only 51% of men and 75% of women regularly interacted with clinicians for counseling opportunities.

CONCLUSIONS: Among low-risk adults with stage 1 hypertension, substantial benefits to cardiovascular health could be achieved through public policy that promotes the adoption of nonpharmacologic therapy.

Smith, Sidney C, Dhruv S Kazi, Cheryl A M Anderson, Craig Beam, Douglas S Boyle, Kelly Griesenbeck Carter, Mitchell S Elkind V, et al. (2024) 2024. “International Initiatives of the American Heart Association: Original Concepts, Present Programs, and Future Focus: A Science Advisory From the American Heart Association.”. Circulation 150 (12): e259-e266. https://doi.org/10.1161/CIR.0000000000001266.

The American Heart Association (AHA), founded in 1924, is anchored in the core belief that scientific research can lead the way to better prevention, treatment, recovery, and ultimately a cure for cardiovascular disease. Historically, the association's involvement in international efforts centered on scientific cooperation. Activities mostly involved AHA leadership presenting at international scientific meetings and leaders from other countries sharing scientific and medical information at AHA meetings. Although the AHA's and American Stroke Association's international efforts have expanded substantially since those early days, global knowledge exchange remains the bedrock of its international endeavors. As the AHA turns 100, we reflect on the successful global efforts in prevention, resuscitation, global advocacy, quality improvement, and health equity that have guided the organization to a place of readiness for "advancing health and hope, for everyone, everywhere." Motivated by the enormous potential for population health gains in an aging world, the AHA is entering its second century with redoubled commitment to improving global cardiovascular and cerebrovascular health for all.

Ferro, Enrico G, Matthew R Reynolds, Jiaman Xu, Yang Song, David J Cohen, Rishi K Wadhera, Andre D’Avila, Peter J Zimetbaum, Robert W Yeh, and Daniel B Kramer. (2024) 2024. “Outcomes of Atrial Fibrillation Ablation Among Older Adults in the United States: A Nationwide Study.”. JACC. Clinical Electrophysiology 10 (7 Pt 1): 1341-50. https://doi.org/10.1016/j.jacep.2024.03.032.

BACKGROUND: Pulmonary vein isolation (PVI) is increasingly recommended as first-line therapy for atrial fibrillation. Recent data suggest growing PVI volumes but rising complication rates, although comprehensive real-world outcomes including both inpatient and outpatient encounters remain unclear.

OBJECTIVES: The purpose of this study was to evaluate patient characteristics, population rates, and 30-day outcomes of PVI in a nationwide sample of U.S. adults aged >65 years.

METHODS: First-time PVIs were identified among U.S. Medicare fee-for-service beneficiaries using Current Procedural Terminology procedural codes. Comorbidities were ascertained using International Classification of Diseases-10th Revision diagnosis codes associated with each procedural claim. Outcomes included periprocedural complications, all-cause hospitalizations, and mortality at 30 days.

RESULTS: From January 2017 through December 2021, a total of 227,133 patients underwent PVI (mean age 72.5 years, 42% women, 92.7% White) with an increasing comorbidity burden over time. PVI volume increased from 83.8 (2017) to 111.6 per 100,000 patient-years (2021), which was driven by outpatient procedures (87.8% of all PVIs). Concurrently, there was a significant decrease in complication rates (3.9% in 2017 vs 3.1% in 2021; P < 0.001) and hospitalizations (8.8% vs 7.0%; P < 0.001), with no significant change in mortality (0.4%; P = 0.08). The most common periprocedural complications were bleeding (1.8%), pericardial effusion (1.4%), and vascular access damage (0.8%).

CONCLUSIONS: The use of PVI has steadily increased among older patients in contemporary U.S. clinical practice; yet, cumulative complication and hospitalization rates at 30 days have decreased over time, with stably low rates of short-term mortality despite rising comorbidity burden among treated patients. These data may reassure patients and providers on the safety of PVI as an increasingly common first-line procedure for atrial fibrillation.

Thompson, Michael P, Hechuan Hou, Donald S Likosky, Francis D Pagani, Jason R Falvey, Kathryn H Bowles, Rishi K Wadhera, and Madeline R Sterling. (2024) 2024. “Home Health Care Use and Outcomes After Coronary Artery Bypass Grafting Among Medicare Beneficiaries.”. Circulation. Cardiovascular Quality and Outcomes 17 (7): e010459. https://doi.org/10.1161/CIRCOUTCOMES.123.010459.

BACKGROUND: Home health care (HHC) has been increasingly used to improve care transitions and avoid poor outcomes, but there is limited data on its use and efficacy following coronary artery bypass grafting. The purpose of this study was to describe HHC use and its association with outcomes among Medicare beneficiaries undergoing coronary artery bypass grafting.

METHODS: Retrospective analysis of 100% of Medicare fee-for-service files identified 77 331 beneficiaries undergoing coronary artery bypass grafting and discharged to home between July 2016 and December 2018. The primary exposure of HHC use was defined as the presence of paid HHC claims within 30 days of discharge. Hierarchical logistic regression identified predictors of HHC use and the percentage of variation in HHC use attributed to the hospital. Propensity-matched logistic regression compared mortality, readmissions, emergency department visits, and cardiac rehabilitation enrollment at 30 and 90 days after discharge between HHC users and nonusers.

RESULTS: A total of 26 751 (34.6%) of beneficiaries used HHC within 30 days of discharge, which was more common among beneficiaries who were older (72.9 versus 72.5 years), male (79.4% versus 77.4%), White (90.2% versus 89.2%), and not Medicare-Medicaid dual eligible (6.7% versus 8.8%). The median hospital-level rate of HHC use was 31.0% (interquartile range, 13.7%-54.5%) and ranged from 0% to 94.2%. Nearly 30% of the interhospital variation in HHC use was attributed to the discharging hospital (intraclass correlation coefficient, 0.296 [95% CI, 0.275-0.318]). Compared with non-HHC users, those using HHC were less likely to have a readmission or emergency department visit, were more likely to enroll in cardiac rehabilitation, and had modestly higher mortality within 30 or 90 days of discharge.

CONCLUSIONS: A third of Medicare beneficiaries undergoing coronary artery bypass grafting used HHC within 30 days of discharge, with wide interhospital variation in use and mixed associations with clinical outcomes and health care utilization.

Park, Sungchul, and Rishi K Wadhera. (2024) 2024. “Use Of High- And Low-Value Health Care Among US Adults, By Income, 2010-19.”. Health Affairs (Project Hope) 43 (7): 1021-31. https://doi.org/10.1377/hlthaff.2023.00661.

Health care payment reforms in the US have aimed to encourage the use of high-value care while discouraging the use of low-value care. However, little is known about whether the use of high- and low-value care differs by income level. Using data from the 2010-19 Medical Expenditure Panel Survey, we examined the use of specified types of high- and low-value care by income level. We found that high-income adults were significantly more likely than low-income adults to use nearly all types of high-value care. Findings were consistent across age categories, although differences by income level in the use of high-value care were smaller among the elderly. Our analysis of differences in the use of low-value care had mixed results. Among nonelderly adults, significant differences between those with high and low incomes were found for five of nine low-value services, and among elderly adults, significant differences by income level were found for three of twelve low-value services. Understanding the mechanisms underlying these disparities is crucial to developing effective policies and interventions to ensure equitable access to high-value care and discourage low-value services for all patients, regardless of income.