What is the Marginal CostEffectiveness of EBCT in an Asymptomatic Screening Population Compared to C

1
What is the Marginal Cost-Effectiveness of EBCT
in an Asymptomatic Screening Population?
(Compared to Conventional Risk Prediction)

• Allen J. Taylor MD,FACC
• Prospective Army Coronary Calcium (PACC) Project
• Walter Reed Army Medical Center, Washington, D.C.
• Uniformed Services University, Bethesda, MD

2
Background

• Risk factors underestimate CVD risk
• Screening EBCT Rationale
• Risk of CVD (4-fold) if Ca present
• High are low risk by risk factors
• Potential to capture misclassificatied risk
• Costs of screening for sub-clinical CVD are
  poorly understood

3
Base Case Assumptions

• Life Expectancy (for average 40yo, 80M)
• At Risk 35 years
• Low Risk 40 years
• Utility of taking medications
• 0.98
• Efficacy of Primary Prevention
• 30 RRR in mortality
• EBCT CAC increases RR by 4

4
ResultsCost Per Quality-Adjusted Life Year

• 90,000 per QALY for base case
• Expensive by conventional standards
• Most sensitive to the
• Efficacy of primary prevention
• Utility of taking life-long medications
• Independent prognostic value of EBCT

5
Tornado Diagram of Important Variables
Efficacy of Primary Prevention
50 RR
10 RR
Utility on Medication
0.99
0.90
Incidental Finding
2
20
Cost of Medications
100
600
Cost of EBCT
800
200
10K
90K
200K
6
Limitations

• Cost per case identified difficult to interpret
• per QALY requires many assumptions
• Efficacy of risk identification not truly known
• Prognostic value of calcification above
  conventional risk factor modeling is still
  controversial
• Modeled 40yo asymptomatic population only
• May not be generalizable to older populations

7
Conclusions

• EBCT identifies a substantial number at risk,
  at a cost of 2990 per additional at risk case
• The marginal COST/QALY is dependent on
• Value of CAC over FRI (gt4-fold)
• Cost and utility of medication (lt 300/yr)
• Incidental findings on EBCT (lt 10)
• Efficacy of primary prevention (gt 25 RRR)
• Our base case using favorable assumptions
  indicated EBCT screening costs 75,000/QALY

8
Implications

• Health systems, insurers and society need to
  understand the costs of new technologies that
  screen for coronary disease
• Modeling can help assess the added value (or
  harm) of new technology where there is
  substantial uncertainty