Publications

2019

Lin, John K, Andrew E Moran, Kirsten Bibbins-Domingo, Bode Falase, Andrea Pedroza Tobias, Charuta N Mandke, and Dhruv S Kazi. (2019) 2019. “Cost-Effectiveness of a Fixed-Dose Combination Pill for Secondary Prevention of Cardiovascular Disease in China, India, Mexico, Nigeria, and South Africa: A Modelling Study.”. The Lancet. Global Health 7 (10): e1346-e1358. https://doi.org/10.1016/S2214-109X(19)30339-0.

BACKGROUND: Fewer than 25% of patients with atherosclerotic cardiovascular disease in countries of low and middle income (LMICs) use guideline-directed drugs for secondary prevention. A fixed-dose combination polypill might improve cardiovascular outcomes by increasing prescription rates and adherence, but the cost-effectiveness of this approach is uncertain.

METHODS: We developed microsimulation models to assess the cost-effectiveness of a polypill containing aspirin, lisinopril, atenolol, and simvastatin for secondary prevention of atherosclerotic cardiovascular disease compared with current care in China, India, Mexico, Nigeria, and South Africa. We modelled baseline use of secondary prevention drugs on the Prospective Urban Rural Epidemiological study. In the intervention arm, we assumed that patients currently prescribed any prevention drug for atherosclerotic cardiovascular disease would receive the polypill instead, which would improve adherence by 32% (from a meta-analysis of two randomised trials in LMICs). We assessed the cost-effectiveness of the polypill at prices in the public sector and on the retail market. Key outcomes were major adverse cardiovascular events (cardiovascular death, non-fatal myocardial infarction, or non-fatal stroke) over a 5-year period and the incremental cost-effectiveness ratio (ICER) from the perspective of the health-care sector and a lifetime analytical horizon. We assumed a cost-effectiveness threshold equal to each country's per capita gross domestic product (GDP) per disability-adjusted life-year (DALY) averted. In sensitivity analyses, we examined the population health effect achievable by increasing the uptake of the polypill in the eligible population.

FINDINGS: Among adults aged 30-84 years with established atherosclerotic cardiovascular disease, adoption of the polypill for secondary prevention compared with current care was projected to avert 40-54 major adverse cardiovascular events for every 1000 patients treated for 5 years and produce between three and ten additional serious adverse events. Assuming public-sector pharmaceutical prices, the ICER of the polypill compared with current care over a lifetime analytical horizon was Int$168 (95% UI 55 to 337) per DALY averted in China, $154 (57 to 289) in India, $88 (15 to 193) in Mexico, $364 (147 to 692) in Nigeria, and $64 (cost-saving to 203) in South Africa, amounting to 0·4-6·2% of the per capita GDP in these countries. The ICER of the polypill compared with current care increased to 3·3-14·6% of the per capita GDP at retail market pharmaceutical prices. Use of the polypill at current rates of prescription of secondary prevention drugs would produce modest health benefits, reducing DALYs from atherosclerotic cardiovascular disease among patients with established disease by 3·1-10·1% over 10 years. Increasing use to 50% or 75% of the eligible population would produce substantially larger health gains (up to 24·3% atherosclerotic cardiovascular disease DALYs averted).

INTERPRETATION: The polypill is projected to be cost-effective compared with current care for secondary prevention of atherosclerotic cardiovascular disease in China, India, Mexico, Nigeria, and South Africa, particularly if it is made available at public-sector pricing. However, achieving meaningful improvements in cardiovascular health will require simultaneous investments in health infrastructure to increase the uptake of the polypill among patients with established atherosclerotic cardiovascular disease.

FUNDING: Richard A and Susan F Smith Center for Outcomes Research in Cardiology, Hellman Family Foundation, Department of Veterans Affairs, and University of California at San Francisco.

Kohli-Lynch, Ciaran N, Brandon K Bellows, George Thanassoulis, Yiyi Zhang, Mark J Pletcher, Eric Vittinghoff, Michael J Pencina, Dhruv Kazi, Allan D Sniderman, and Andrew E Moran. (2019) 2019. “Cost-Effectiveness of Low-Density Lipoprotein Cholesterol Level-Guided Statin Treatment in Patients With Borderline Cardiovascular Risk.”. JAMA Cardiology 4 (10): 969-77. https://doi.org/10.1001/jamacardio.2019.2851.

IMPORTANCE: American College of Cardiology/American Heart Association cholesterol guidelines prioritize primary prevention statin therapy based on 10-year absolute risk (AR10) of atherosclerotic cardiovascular disease (ASCVD). However, given the same AR10, patients with higher levels of low-density lipoprotein cholesterol (LDL-C) experience greater absolute risk reduction from statin therapy.

OBJECTIVES: To estimate the cost-effectiveness of expanding preventive statin treatment eligibility from standard care to patients at borderline risk (AR10, 5.0%-7.4%) for ASCVD and with high levels of LDL-C and to estimate cost-effectiveness of statin treatment across ranges of age, sex, AR10, and LDL-C levels.

DESIGN, SETTING, AND PARTICIPANTS: This study evaluated 100 simulated cohorts, each including 1 million ASCVD-free survey respondents (50% men and 50% women) aged 40 years at baseline. Cohorts were created by probabilistic sampling of the 1999-2014 US National Health and Nutrition Examination Surveys from the perspective of the US health care sector. The CVD Policy Model microsimulation version projected lifetime health and cost outcomes. Probability of first-ever coronary heart disease or stroke event was estimated by analysis of 6 pooled US cohort studies and recalibrated to match contemporary event rates. Other model variables were derived from national surveys, meta-analyses, and published literature. Data were analyzed from May 15, 2018, through June 10, 2019.

EXPOSURES: Four statin treatment strategies were compared: (1) treat all patients with AR10 of at least 7.5%, diabetes, or LDL-C of at least 190 mg/dL (standard care); (2) add treatment for borderline risk and LDL-C levels of 160 to 189 mg/dL; (3) add treatment for borderline risk and LDL-C levels of 130 to 159 mg/dL; and (4) add treatment for remainder of patients with AR10 of at least 5.0%. Statin treatment was also compared with no statin treatment in age, sex, AR10, and LDL-C strata.

MAIN OUTCOMES AND MEASURES: Lifetime quality-adjusted life-years (QALYs) and costs (2019 US dollars) were projected and discounted 3.0% annually. The primary outcome was the incremental cost-effectiveness ratio.

RESULTS: In these 100 simulated cohorts, each with 1 million patients aged 40 years at baseline (50% women and 50% men), adding preventive statins to individuals with borderline AR10 and LDL-C levels of 160 to 189 mg/dL would be cost-saving; further treating borderline AR10 and LDL-C levels of 130 to 159 mg/dL would also be cost-saving; and treating all individuals with AR10 of at least 5.0% would be highly cost-effective ($33 558/QALY) and would prevent the most ASCVD events. Within age, AR10, and sex categories, individuals with higher baseline LDL-C levels gained more QALYs from statin therapy. Cost-effectiveness increased with LDL-C level and AR10.

CONCLUSIONS AND RELEVANCE: In this study, lifetime statin treatment of patients in a hypothetical cohort with borderline ASCVD risk and LDL-C levels of 160 to 189 mg/dL was found to be cost-saving. Results suggest that treating all patients at borderline risk regardless of LDL-C level would likely be highly cost-effective.

Kazi, Dhruv S, and Salim S Virani. (2019) 2019. “Implications of Cost-Effectiveness Analyses of Lipid-Lowering Therapies: From the Policy-Maker’s Desk to the Patient’s Bedside.”. Progress in Cardiovascular Diseases 62 (5): 406-13. https://doi.org/10.1016/j.pcad.2019.10.006.

In our increasingly cost-conscious health system, patients, clinicians, hospitals, and payers all agree about the urgent need to rein in runaway healthcare costs. High pharmaceutical costs make drugs unaffordable to many patients who may benefit from them, including some insured patients who face prohibitive out-of-pocket costs. Health systems and payers can use the systematic framework of cost-effectiveness analysis and estimated budgetary impact to prioritize the adoption of new therapies and technologies. In this review article, we discuss basic principles of cost-effectiveness research for practicing clinicians, the concept of cost-effectiveness versus affordability, other considerations relevant to resource allocation, and limitations of cost-effectiveness research. We use the example of lipid lowering therapies to discuss application of cost-effectiveness research in informing health care policy, its use for health care systems and in the development of clinical practice guidelines, and its implications for clinicians and patients. As clinicians and patients become more cognizant of the cost-implications of new therapies, professional societies can help improve the quality of decision-making by incorporating unbiased value statements into their expert guidelines.

Kundi, Harun, Rishi K Wadhera, Jordan B Strom, Linda R Valsdottir, Changyu Shen, Dhruv S Kazi, and Robert W Yeh. (2019) 2019. “Association of Frailty With 30-Day Outcomes for Acute Myocardial Infarction, Heart Failure, and Pneumonia Among Elderly Adults.”. JAMA Cardiology 4 (11): 1084-91. https://doi.org/10.1001/jamacardio.2019.3511.

IMPORTANCE: The addition of a claims-based frailty metric to traditional comorbidity-based risk-adjustment models for acute myocardial infarction (AMI), heart failure (HF), and pneumonia improves the prediction of 30-day mortality and readmission. This may have important implications for hospitals that tend to care for frail populations and participate in Centers for Medicare & Medicaid Services value-based payment programs, which use these risk-adjusted metrics to determine reimbursement.

OBJECTIVE: To determine whether the addition of frailty measures to traditional comorbidity-based risk-adjustment models improved prediction of outcomes for patients with AMI, HF, and pneumonia.

DESIGN, SETTING, AND PARTICIPANTS: A nationwide cohort study included Medicare fee-for-service beneficiaries 65 years and older in the United States between January 1 and December 1, 2016. Analysis began August 2018.

MAIN OUTCOMES AND MEASURES: Rates of mortality within 30 days of admission and 30 days of discharge, as well as 30-day readmission rates by frailty group. We evaluated the incremental effect of adding the Hospital Frailty Risk Score (HFRS) to current comorbidity-based risk-adjustment models for 30-day outcomes across all conditions.

RESULTS: For 785 127 participants, there were 166 200 hospitalizations [21.2%] for AMI, 348 619 [44.4%] for HF, and 270 308 [34.4%] for pneumonia. The mean (SD) age at the time of hospitalization was 79.2 (8.9) years; 656 315 (83.6%) were white and 402 639 (51.3%) were women. The mean (SD) HFRS was 7.3 (7.4) for patients with AMI, 10.8 (8.3) for patients with HF, and 8.2 (5.7) for patients with pneumonia. Among patients hospitalized for AMI, an HFRS more than 15 (compared with an HFRS <5) was associated with a higher risk of 30-day postadmission mortality (adjusted odds ratio [aOR], 3.6; 95% CI, 3.4-3.8), 30-day postdischarge mortality (aOR, 4.0; 95% CI, 3.7-4.3), and 30-day readmission (aOR, 3.0; 95% CI, 2.9-3.1) after multivariable adjustment for age, sex, race, and comorbidities. Similar patterns were observed for patients hospitalized with HF (30-day postadmission mortality: aOR, 3.5; 95% CI, 3.4-3.7; 30-day postdischarge mortality: aOR, 3.5; 95% CI, 3.3-3.6; and 30-day readmission: aOR, 2.9; 95% CI, 2.8-3.0) and among patients with pneumonia (30-day postadmission mortality: aOR, 2.5; 95% CI, 2.3-2.6; 30-day postdischarge mortality: aOR, 3.0; 95% CI, 2.9-3.2; and 30-day readmission: aOR, 2.8; 95% CI, 2.7-2.9). The addition of HFRS to traditional comorbidity-based risk-prediction models improved discrimination to predict outcomes for all 3 conditions.

CONCLUSIONS AND RELEVANCE: Among Medicare fee-for-service beneficiaries, frailty as measured by the HFRS was associated with mortality and readmissions among patients hospitalized for AMI, HF, or pneumonia. The addition of HFRS to traditional comorbidity-based risk-prediction models improved the prediction of outcomes for all 3 conditions.

2018

Chen, Shu, Enying Gong, Dhruv S Kazi, Ann B Gates, Rong Bai, Hua Fu, Weixia Peng, et al. (2018) 2018. “Using Mobile Health Intervention to Improve Secondary Prevention of Coronary Heart Diseases in China: Mixed-Methods Feasibility Study.”. JMIR MHealth and UHealth 6 (1): e9. https://doi.org/10.2196/mhealth.7849.

BACKGROUND: Coronary heart disease (CHD) is the leading cause of cardiovascular mortality worldwide, yet implementation of evidence-based strategies for secondary prevention remains suboptimal.

OBJECTIVE: This study aimed to evaluate the feasibility, specifically the usability and acceptability, and estimate the preliminary effectiveness of a mobile health (mHealth) intervention targeting both physicians and patients to improve adherence to evidence-based medications and lifestyle modifications.

METHODS: We conducted a 12-week pre-post interventional pilot study at two sites in Shanghai and Hainan, China. Physicians used the app designed in this study to prescribe evidence-based medicines and record patient information. Eligible and consenting patients received automatic text messages or voice calls 4 to 5 times per week for 12 weeks on medication adherence and healthy behaviors. Interviews were conducted among 10 physicians and 24 patients at the two sites for their thoughts on medication adherence and feedback on the usability and acceptability. Questions on usability and acceptability were also asked in a patient follow-up survey. With regard to estimating effectiveness, the primary outcome was medication adherence (as estimated by the Morisky Green Levine Scale) at 12 weeks. Secondary outcomes included physical activity, smoking status, fruits and vegetables consumption, and facility visit frequency.

RESULTS: Interview findings and patient survey showed the good usability and acceptability of the intervention. Among 190 patients who completed the intervention, there was a significant increase in medication adherence (odds ratio [OR] 1.80, 95% CI 1.14-2.85). The study also showed decrease of smokers' percentage (-5%, P=.05), increase of daily vegetables consumption frequency (+0.3/day, P=.01), and community health care center visit frequency (+3 in 3 months, P=.04). The following site-specific differences were noted: medication adherence appeared to increase in Hainan (OR 14.68, 95% CI 5.20-41.45) but not in Shanghai (OR 0.61, 95% CI 0.33-1.12).

CONCLUSIONS: Our study demonstrated that the intervention was feasible in both a tertiary care center and an urban community health center in China. Preliminary results from pre-post comparison suggest the possibility that provider and patient-linked mHealth interventions may improve medication adherence and lifestyle modifications among CHD patients, especially in resource-scarce settings. Randomized controlled trials are needed to verify the findings.