Publications

2017

Kazi, Dhruv S, Joanne M Penko, and Kirsten Bibbins-Domingo. (2017) 2017. “Statins for Primary Prevention of Cardiovascular Disease: Review of Evidence and Recommendations for Clinical Practice.”. The Medical Clinics of North America 101 (4): 689-99. https://doi.org/10.1016/j.mcna.2017.03.001.
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Numerous large randomized clinical trials have shown that statin therapy is effective and safe for primary prevention of atherosclerotic cardiovascular disease (CVD) for adults aged 40 to 75 years and support the use of 10-year CVD risk as a means to identify individuals for treatment. Uncertainty exists in those older than 75 years who may be more likely to benefit because of their underlying CVD risk, but also face uncertain harms. Several high-quality mathematical simulation models have shown that statin therapy is cost-effective for primary prevention of atherosclerotic CVD. Despite effectiveness and safety, statins are underutilized for primary prevention.

Heller, David J, Pamela G Coxson, Joanne Penko, Mark J Pletcher, Lee Goldman, Michelle C Odden, Dhruv S Kazi, and Kirsten Bibbins-Domingo. (2017) 2017. “Evaluating the Impact and Cost-Effectiveness of Statin Use Guidelines for Primary Prevention of Coronary Heart Disease and Stroke.”. Circulation 136 (12): 1087-98. https://doi.org/10.1161/CIRCULATIONAHA.117.027067.
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BACKGROUND: Statins are effective in the primary prevention of atherosclerotic cardiovascular disease. The 2013 American College of Cardiology/American Heart Association (ACC/AHA) guideline expands recommended statin use, but its cost-effectiveness has not been compared with other guidelines.

METHODS: We used the Cardiovascular Disease Policy Model to estimate the cost-effectiveness of the ACC/AHA guideline relative to current use, Adult Treatment Panel III guidelines, and universal statin use in all men 45 to 74 years of age and women 55 to 74 years of age over a 10-year horizon from 2016 to 2025. Sensitivity analyses varied costs, risks, and benefits. Main outcomes were incremental cost-effectiveness ratios and numbers needed to treat for 10 years per quality-adjusted life-year gained.

RESULTS: Each approach produces substantial benefits and net cost savings relative to the status quo. Full adherence to the Adult Treatment Panel III guideline would result in 8.8 million more statin users than the status quo, at a number needed to treat for 10 years per quality-adjusted life-year gained of 35. The ACC/AHA guideline would potentially result in up to 12.3 million more statin users than the Adult Treatment Panel III guideline, with a marginal number needed to treat for 10 years per quality-adjusted life-year gained of 68. Moderate-intensity statin use in all men 45 to 74 years of age and women 55 to 74 years of age would result in 28.9 million more statin users than the ACC/AHA guideline, with a marginal number needed to treat for 10 years per quality-adjusted life-year gained of 108. In all cases, benefits would be greater in men than women. Results vary moderately with different risk thresholds for instituting statins and statin toxicity estimates but depend greatly on the disutility caused by daily medication use (pill burden).

CONCLUSIONS: At a population level, the ACC/AHA guideline for expanded statin use for primary prevention is projected to treat more people, to save more lives, and to cost less compared with Adult Treatment Panel III in both men and women. Whether individuals benefit from long-term statin use for primary prevention depends more on the disutility associated with pill burden than their degree of cardiovascular risk.

Kazi, Dhruv S, Gregg Greenough, Rishi Madhok, Aaron Heerboth, Ahmed Shaikh, Jennifer Leaning, and Satchit Balsari. (2017) 2017. “Using Mobile Technology to Optimize Disease Surveillance and Healthcare Delivery at Mass Gatherings: A Case Study from India’s Kumbh Mela.”. Journal of Public Health (Oxford, England) 39 (3): 616-24. https://doi.org/10.1093/pubmed/fdw091.
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Publisher's Version

BACKGROUND: Planning for mass gatherings often includes temporary healthcare systems to address the needs of attendees. However, paper-based record keeping has traditionally precluded the timely application of collected clinical data for epidemic surveillance or optimization of healthcare delivery. We evaluated the feasibility of harnessing ubiquitous mobile technologies for conducting disease surveillance and monitoring resource utilization at the Allahabad Kumbh Mela in India, a 55-day festival attended by over 70 million people.

METHODS: We developed an inexpensive, tablet-based customized disease surveillance system with real-time analytic capabilities, and piloted it at five field hospitals.

RESULTS: The system captured 49 131 outpatient encounters over the 3-week study period. The most common presenting complaints were musculoskeletal pain (19%), fever (17%), cough (17%), coryza (16%) and diarrhoea (5%). The majority of patients received at least one prescription. The most common prescriptions were for antimicrobials, acetaminophen and non-steroidal anti-inflammatory drugs. There was great inter-site variability in caseload with the busiest hospital seeing 650% more patients than the least busy hospital, despite identical staffing.

CONCLUSIONS: Mobile-based health information solutions developed with a focus on user-centred design can be successfully deployed at mass gatherings in resource-scarce settings to optimize care delivery by providing real-time access to field data.

Hlatky, Mark A, and Dhruv S Kazi. (2017) 2017. “PCSK9 Inhibitors: Economics and Policy.”. Journal of the American College of Cardiology 70 (21): 2677-87. https://doi.org/10.1016/j.jacc.2017.10.001.
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Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors substantially reduce low-density lipoprotein cholesterol, but it is presently unclear whether they also reduce mortality. The list prices of PCSK9 inhibitors in the United States (>$14,500 per year) are >100× higher than generic statins, and only a small fraction of their higher cost is likely to be recovered by prevention of cardiovascular events. The projected cost effectiveness of PCSK9 inhibitors does not meet generally accepted benchmarks for good value in the United States, but their value would be improved by substantial price reductions. For individual patients, the high out-of-pocket costs of PCSK9 inhibitors may impede access and reduce long-term adherence. The budgetary impact of PCSK9 inhibitors would be very large if all potentially eligible patients were treated, which poses dilemmas for policymakers, payers, and society.

2016

Schoenfeld, Adam J, Jason M Davies, Ben J Marafino, Mitzi Dean, Colette DeJong, Naomi S Bardach, Dhruv S Kazi, et al. (2016) 2016. “Variation in Quality of Urgent Health Care Provided During Commercial Virtual Visits.”. JAMA Internal Medicine 176 (5): 635-42. https://doi.org/10.1001/jamainternmed.2015.8248.
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Publisher's Version

IMPORTANCE: Commercial virtual visits are an increasingly popular model of health care for the management of common acute illnesses. In commercial virtual visits, patients access a website to be connected synchronously-via videoconference, telephone, or webchat-to a physician with whom they have no prior relationship. To date, whether the care delivered through those websites is similar or quality varies among the sites has not been assessed.

OBJECTIVE: To assess the variation in the quality of urgent health care among virtual visit companies.

DESIGN, SETTING, AND PARTICIPANTS: This audit study used 67 trained standardized patients who presented to commercial virtual visit companies with the following 6 common acute illnesses: ankle pain, streptococcal pharyngitis, viral pharyngitis, acute rhinosinusitis, low back pain, and recurrent female urinary tract infection. The 8 commercial virtual visit websites with the highest web traffic were selected for audit, for a total of 599 visits. Data were collected from May 1, 2013, to July 30, 2014, and analyzed from July 1, 2014, to September 1, 2015.

MAIN OUTCOMES AND MEASURES: Completeness of histories and physical examinations, the correct diagnosis (vs an incorrect or no diagnosis), and adherence to guidelines of key management decisions.

RESULTS: Sixty-seven standardized patients completed 599 commercial virtual visits during the study period. Histories and physical examinations were complete in 417 visits (69.6%; 95% CI, 67.7%-71.6%); diagnoses were correctly named in 458 visits (76.5%; 95% CI, 72.9%-79.9%), and key management decisions were adherent to guidelines in 325 visits (54.3%; 95% CI, 50.2%-58.3%). Rates of guideline-adherent care ranged from 206 visits (34.4%) to 396 visits (66.1%) across the 8 websites. Variation across websites was significantly greater for viral pharyngitis and acute rhinosinusitis (adjusted rates, 12.8% to 82.1%) than for streptococcal pharyngitis and low back pain (adjusted rates, 74.6% to 96.5%) or ankle pain and recurrent urinary tract infection (adjusted rates, 3.4% to 40.4%). No statistically significant variation in guideline adherence by mode of communication (videoconference vs telephone vs webchat) was found.

CONCLUSIONS AND RELEVANCE: Significant variation in quality was found among companies providing virtual visits for management of common acute illnesses. More variation was found in performance for some conditions than for others, but no variation by mode of communication.

Kazi, Dhruv S, Andrew E Moran, Pamela G Coxson, Joanne Penko, Daniel A Ollendorf, Steven D Pearson, Jeffrey A Tice, David Guzman, and Kirsten Bibbins-Domingo. (2016) 2016. “Cost-Effectiveness of PCSK9 Inhibitor Therapy in Patients With Heterozygous Familial Hypercholesterolemia or Atherosclerotic Cardiovascular Disease.”. JAMA 316 (7): 743-53. https://doi.org/10.1001/jama.2016.11004.
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Publisher's Version

IMPORTANCE: Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors were recently approved for lowering low-density lipoprotein cholesterol in heterozygous familial hypercholesterolemia (FH) or atherosclerotic cardiovascular disease (ASCVD) and have potential for broad ASCVD prevention. Their long-term cost-effectiveness and effect on total health care spending are uncertain.

OBJECTIVE: To estimate the cost-effectiveness of PCSK9 inhibitors and their potential effect on US health care spending.

DESIGN, SETTING, AND PARTICIPANTS: The Cardiovascular Disease Policy Model, a simulation model of US adults aged 35 to 94 years, was used to evaluate cost-effectiveness of PCSK9 inhibitors or ezetimibe in heterozygous FH or ASCVD. The model incorporated 2015 annual PCSK9 inhibitor costs of $14,350 (based on mean wholesale acquisition costs of evolocumab and alirocumab); adopted a health-system perspective, lifetime horizon; and included probabilistic sensitivity analyses to explore uncertainty.

EXPOSURES: Statin therapy compared with addition of ezetimibe or PCSK9 inhibitors.

MAIN OUTCOMES AND MEASURES: Lifetime major adverse cardiovascular events (MACE: cardiovascular death, nonfatal myocardial infarction, or stroke), incremental cost per quality-adjusted life-year (QALY), and total effect on US health care spending over 5 years.

RESULTS: Adding PCSK9 inhibitors to statins in heterozygous FH was estimated to prevent 316,300 MACE at a cost of $503,000 per QALY gained compared with adding ezetimibe to statins (80% uncertainty interval [UI], $493,000-$1,737,000). In ASCVD, adding PCSK9 inhibitors to statins was estimated to prevent 4.3 million MACE compared with adding ezetimibe at $414,000 per QALY (80% UI, $277,000-$1,539,000). Reducing annual drug costs to $4536 per patient or less would be needed for PCSK9 inhibitors to be cost-effective at less than $100,000 per QALY. At 2015 prices, PCSK9 inhibitor use in all eligible patients was estimated to reduce cardiovascular care costs by $29 billion over 5 years, but drug costs increased by an estimated $592 billion (a 38% increase over 2015 prescription drug expenditures). In contrast, initiating statins in these high-risk populations in all statin-tolerant individuals who are not currently using statins was estimated to save $12 billion.

CONCLUSIONS AND RELEVANCE: Assuming 2015 prices, PCSK9 inhibitor use in patients with heterozygous FH or ASCVD did not meet generally acceptable incremental cost-effectiveness thresholds and was estimated to increase US health care costs substantially. Reducing annual drug prices from more than $14,000 to $4536 would be necessary to meet a $100,000 per QALY threshold.