cost-effectiveness of coronary calcium testing to guide statin therapy
DESCRIPTION
Presented by Mark Pletcher, MD, MPH, at UCSF's symposium "The Role of Risk Stratification and Biomarkers in Prevention of Cardiovascular Disease" in Jan 2012.TRANSCRIPT
Cost-effectiveness of coronary calcium testing to
guide statin therapy:Preliminary Results
CVD Risk Biomarker SymposiumMark J. Pletcher, MD, MPH
1/30/2012
Goals
• Compare Test-and-Treat strategies against Treat none and Treat all– For different age/sex/risk groups– Comparing different CAC score thresholds– Varying key parameters
• Statin price, time horizon, cost of testing
The CAC version of the model
Key Inputs
Key Inputs
• CAC relative risks from MESA– 0 ref– 1-100 3.61– 101-300 7.73– 300+ 9.67
NEJM 2008;358:1336-45
Key Inputs
• Prevalence of CAC, conditional on other CHD risk factors
• Integrate CAC RR’s with prevalence to get CAC category-specific absolute risk
BMC Medicine 2004;2:31
Key Inputs
• CAC scan cost– Test itself: $107.03 (vs. $200 or $300)– Physician visit to discuss results: $71.01– Total testing cost = $178.04
Other key parameters
• Statin cost– Pills $4/month = $0.13/day (vs. $1.00/day)– Extra physician visit/year = $68.97– Extra lipid panel/year = $23.44– Total annual cost = $140.96
• Time horizon– 10 years (vs. 25 years)
• Willingness to pay– $50,000/QALY
45 yo man with 5% risk
Statins = $0.13 / day
10-year horizon
Preliminary Results
45 yo man with 5% risk
Steeper “slope” (good - depends of CAC RR)
Shifted to the right (bad – depends on CAC $)
Medium effectiveness (depends on # treated, prev of CAC)
Statins = $0.13 / day
10-year horizon
Preliminary Results
45 yo man with 5% risk
Cost-effectiveness “frontier”
(i.e., Non-dominated strategies)
Statins = $0.13 / day
10-year horizon
Preliminary Results
45 yo man with 5% risk
ICER for non-dominated strategies
$152,000
$57,000Statins = $0.13 / day
10-year horizon
Preliminary Results
45 yo man with 5% risk
If willingness to pay <$50,000/QALY,
Preferred strategy = Treat none
$152,000
$57,000Statins = $0.13 / day
10-year horizon
Preliminary Results
45 yo man with 15% risk
Statins = $0.13 / day
10-year horizon
Preliminary Results
45 yo man with 10% risk
Statins = $0.13 / day
10-year horizon
$25,000/QALY
Preliminary Results
45 yo man with 7.5% risk
$55,000/QALY
$8,000/QALY
Preliminary Results
By age/risk
• Men, statins=$0.13/day, 10-year horizon• WTC >$50,000
AgeRisk 35 45 55 652.5% --- --- ---5% --- --- >0 >07.5% All >0 >0 >010% All All All All15% All All All All25% All All All All
Preliminary Results
By age/risk
• Men, statins=$0.13/day, 10-year horizon• WTC >$50,000
AgeRisk 35 45 55 652.5% --- --- ---5% --- --- >0 >07.5% All >0 >0 >010% All All All All15% All All All All25% All All All All
Preliminary Results
65 yo man with 7.5% risk
$15,000/QALY
$8,000/QALY
$78,000/QALY
Preliminary Results
By age/risk
• Women, statins=$0.13/day, 10-year horizon• WTC >$50,000
AgeRisk 35 45 55 652.5% --- --- --- ---5% >0 --- --- ---7.5% >0 >0 >0 >10010% >0 >0 All15% All >0 All25% All All All
Preliminary Results
By age/risk
• Women, statins=$0.13/day, 10-year horizon• WTC >$50,000
AgeRisk 35 45 55 652.5% --- --- --- ---5% >0 --- --- ---7.5% >0 >0 >0 >10010% >0 >0 All15% All >0 All25% All All All
Preliminary Results
65 yo Woman with 7.5% risk
$18,000/QALY
$59,000/QALY
Preliminary Results
Sensitivity analyses
• Vary statin price and time horizon
Longer time horizon
• Women, statins=$0.13/day, 25-year horizon• WTC >$50,000
Risk 35 45 55 652.5% >0 >0 >0 >1005% All >0 >0 >07.5% All All >0 All10% All All All15% All All All25% All All All
Preliminary Results
Short horizon, expensive statins
• Women, statins=$1.00/day, 10-year horizon• WTC >$50,000
Risk 35 45 55 652.5% --- --- --- ---5% --- --- --- ---7.5% --- --- --- ---10% --- --- ---15% >100 >100 >10025% >0 >0 >0
Preliminary Results
Short horizon, expensive statins (men)
• Men, statins=$1.00/day, 10-year horizon• WTC >$50,000
Risk 35 45 55 652.5% --- --- --- ---5% --- --- --- ---7.5% --- --- --- >10010% --- >0 >0 >10015% >0 >0 >0 >025% >0 >0 >0
Preliminary Results
Results
CAC testing is often cost effective!
Preliminary Results
Results
• Under what conditions is it NOT cost-effective for:
– 55 yo woman, 10% risk
– Statins = $0.13/day
– Time horizon = 10 years
Preliminary Results
By age/risk
• Women, statins=$0.13/day, 10-year horizon• WTC >$50,000
AgeRisk 35 45 55 652.5% --- --- --- ---5% >0 --- --- >07.5% >0 >0 >0 >10010% >0 >0 All15% All >0 All25% All All All
Preliminary Results
By RR/cost
• 55 yo Women, 10% risk• Statins=$0.13/day, 10-year horizon, WTC >$50,000
$/scanCAC RR $300 $200 $107.03
(Base case)x .50 All All Allx .75 All All >0Base case All >0 >0
Preliminary Results
By RR/cost
• 55 yo Women, 10% risk• Statins=$0.13/day, 10-year horizon, WTC >$50,000
$/scanCAC RR $300 $200 $107.03
(Base case)x .50 All All Allx .75 All All >0Base case All >0 >0
Preliminary Results
Base Case
$16,000/QALY
$126,000/QALY
Preliminary Results
If cost of scan = $300Preliminary Results
If CAC is half as useful
$24/QALY
$37,000/QALY
Preliminary Results
Summary
• CAC testing can be a cost-effective way to target statin therapy– Depends on the cost of the scan– Testing thresholds depend on statin price
Preliminary Results
Big questions
• How to deal with statin prices?
• What is the right time horizon?
• Statin effectiveness and CAC prediction at the tails of the age-risk distribution
To do:
• More sensitivity & Monte Carlo analyses
• Radiation-induced cancer from CAC CT
• Other downsides of testing?
• Update CAC prevalence with MESA
• ASA, and ASA+Statins (dif thresholds?)
• Lifetime horizon with delayed treatment
• Online tool…
Thanks
• Questions? Comments?