Project Summary
In 2011 the Institute of Medicine (now the National Academy of Medicine) convened a panel to explore the
paradox of why the US spends more on healthcare than other developed countries yet has inferior outcomes.
It concluded that “Data are simply lacking to fully understand the causal factors responsible for each of the
diseases and injuries that disproportionately affect the US population.” This is still true today. What’s notable is
that the US has shorter life expectancy with the 2nd highest cardiovascular death rate among peer countries
while still having the highest spending in the world (19.7% of gross domestic product).
In 2019 Drs. Cram and Landon founded the International Health Systems Research Collaborative (IHSRC)
with funding from the NIH (NIA R01AG058878) to compare treatment and outcomes across high-income
countries for cohorts of patients defined by common diagnoses and procedures. The current proposal will
leverage and expand upon our IHSRC infrastructure to compare health technology assessment (HTA) across
countries and evaluate how HTA relates to the utilization, adoption, and de-adoption of new cardiovascular
(CV) treatments and procedures. Many countries (including IHSRC members England, Netherlands and
Canada) have explicit HTA processes linked to public insurance coverage decisions for new therapies. The US
is notable for lacking a formal HTA process. While failure to embrace HTA likely contributes to excessively high
spending in the US, few studies have evaluated how different countries approach HTA.
The overarching objective of our research is to understand how advanced CV therapies are adopted and used
in 7 countries with advanced healthcare systems. Our research will focus on 3 cardiovascular condition dyads
where introduction/refinements in advanced therapy is disrupting an established therapy: 1) aortic valve
dysfunction where transcatheter aortic valve replacement (TAVR) is in the process of supplanting surgical
aortic valve replacement (SAVR); 2) elective AAA repair where endovascular aneurysm repair is replacing
open repair; and 3) carotid artery stenosis where trans-carotid artery revascularization (TCAR) and stenting are
emerging as substitutes for carotid endarterectomy. Our research will address major unanswered questions by
providing crucial insights into how advanced technologies are adopted and used in different countries. We will
provide much needed clarity with respect to the ongoing and unanswered question of whether higher spending
in the US can be attributed to more rapid adoption and higher utilization of advanced therapies.
Our proposal has three specific aims that assess: (1) each country’s policy and health technology assessment
environment related to each procedure; (2) technology diffusion patterns in the context of their evolving policy
environments; and (3) differences in outcomes, including mortality, readmissions, and hospital-free days at
home. The scientific premise of our proposal is that granular information is needed to inform the study of
comparative health systems and to understand the adoption and diffusion of new technologies.
