Harvard School of Public Health
A new study from Harvard T.H. Chan School of Public Health researchers has found that it would be cost-effective to treat 48-67% of all adults aged 40-75 in the U.S. with cholesterol-lowering statins.
By expanding
the current recommended treatment guidelines and boosting the percentage of
adults taking statins, an additional 161,560 cardiovascular-related events
could be averted, according to the researchers.
"The
new cholesterol treatment guidelines have been controversial, so our goal for
this study was to use the best available evidence to quantify the tradeoffs in
health benefits, risks, and costs of expanding statin treatment. We found that
the new guidelines represent good value for money spent on healthcare, and that
more lenient treatment thresholds might be justifiable on cost-effectiveness
grounds even accounting for side-effects such as diabetes and myalgia,"
said Ankur Pandya, assistant professor of health decision science at Harvard
Chan School and lead author of the study.
The
percentage of Americans taking statins has jumped in recent years -- as of
2012, 26% of all adults over age 40 were taking them, according to the U.S.
Centers for Disease Control and Prevention (CDC) -- and so has controversy
surrounding their use.
In November 2013, the American Heart Association (AHA)
and the American College of Cardiology (ACC) recommended that statins be
prescribed for people with a 7.5% or greater risk of heart attack or stroke
over a 10-year period, including many with no existing cardiovascular issues.
Previous guidelines had advised statin use only if the risk was 10-20% or
higher.
After
the 2013 recommendations were issued, proponents of expanding statin use said
there was strong evidence that they reduce risk of heart attack and stroke;
critics said the risks were overestimated, that healthy adults would be
overtreated, and that more people would be at increased risk for negative side
effects, such as memory loss, type 2 diabetes, and muscle damage.
The
researchers did a cost-effectiveness analysis of the ACC-AHA guidelines to find
the optimal value for the 10-year CVD risk threshold. They used a measure known
as the quality-adjusted life-year (QALY) -- a measure of the burden of a
disease in terms of both the quality and the quantity of life lived.
QALYs are
frequently used to assess the monetary value of using particular medical
interventions; they are based on the number of years of "quality"
life that would be gained by such interventions. In the U.S. today, health
economists typically consider $100,000/QALY and $150,000/QALY reasonable in
terms of what the public is willing to pay for health gains.
The
researchers found that the current 10-year cardiovascular disease (CVD) risk
threshold (≥7.5%) was acceptable in terms of cost-effectiveness ($37,000/QALY),
but that more lenient treatment thresholds of ≥4.0% or ≥3.0% would be optimal
under criteria of <$100,000/QALY or <$150,000/QALY and would avert an estimated
additional 125,000-160,000 CVD-events.
They also found that the optimal
treatment threshold was particularly sensitive to patient preferences for
taking a pill daily, which suggests that the decision to initiate statins for
primary CVD prevention should be made jointly by patients and physicians.
Other
Harvard Chan School authors of the study included Stephen Sy and Sylvia Cho,
researchers from the Center for Health Decision Science; Milton Weinstein,
Henry J. Kaiser Professor of Health Policy and Management; and senior author
Thomas Gaziano, assistant professor in the Department of Health Policy and
Management and cardiologist at Brigham and Women's Hospital.
Funding
for the study came from grant No. 5R01HL104284-03 to the Harvard T.H. Chan
School of Public Health from the National Heart, Lung, and Blood Institute.