Cardiovascular Disease

1. USING
MICROSIMULATION TO
INFORM TARGETED
CARDIOVASCULAR
DISEASE PREVENTION
POLICY
STEVEN DEHMER, PHD
RESEARCH FELLOW, HEALTHPARTNERS RESEARCH
FOUNDATION
Monday, April 30th HMORN 2012 Conference, Seattle WA

2. Presentation Outline
1) Brief Project Background
2) Description of the CVD Prevention Policy Model
3) Brief Description of Results

3. Project Background
Context:
 Need to identify priority areas for prevention (NCPP)
1) Evidence driven
2) Consistent and comparable
3) Account for disparities and population-specific effects
Purpose:
a) Assess USPSTF recommended cardiovascular clinical
services
b) Assess cardiovascular impacts of other clinical and
community services

4. Project Background
Cardiovascular Clinical Preventive Services (USPSTF):
1) Screening for lipid disorders in adults
 Men (35+ or 20-35 at ↑ risk); Women (20+ at ↑ risk)
2) Hypertension screening for adults (18 and older)
3) Aspirin counseling for primary prevention of CVD
 Men ages 45-79 with increased risk from myocardial infarction
 Women ages 55-79 with increased risk from stroke
 Balance potential CVD benefits with gastrointestinal bleeding risks

5. CVD Prevention Policy Model
Design Overview:
 “Microsimulation” model: start with an individual and
predict lifetime progression of health status and outcomes
 Simulations of many individuals can be aggregated to
estimate population-wide impacts
 Interventions or counterfactuals tested as if in a randomized
controlled trial (here: same people and all else held equal)
 Key benefit of complex design: sub-population effects for
informing targeted policy

6. CVD Prevention Policy Model
Design Overview:
Demographic characteristics:
 Age 20 to 100
 Sex: Male, Female
 Race/ethnicity:
 Non-Hispanic white
 Non-Hispanic black/African American
 Hispanic/Mexican American
 “Other”
Health characteristics (change as an individual ages):
 Body mass index (BMI)
 Cholesterol: LDL, HDL
 Systolic blood pressure (SBP)
 Smoking status
 Disease status

7. CVD Prevention Policy Model
Design Overview:
Cardiovascular disease events:
 Myocardial infarction (MI)
 Ischemic stroke (IS)
 Hemorrhagic stroke (HS)
 Congestive heart failure (CHF)
 Angina pectoris (AP)
 Intermittent claudication (IC)
Related disease:
 Diabetes
Mortality:
 CVD related death
 Non-CVD death

8. CVD Prevention Policy Model

9. CVD Prevention Policy Model
Model Initialization:
 NHANES (1999-2008)
• Sex
• Race/ethnicity
• HDL, LDL
• SBP
 BRFSS (2009)
• BMI

10. CVD Prevention Policy Model
Eligibility for Prevention:
 USPSTF
Recommendations:
1) Lipid screening
2) BP screening
3) Aspirin counseling
 Delivery of untested
recommendations set at
contemporary rates
(NHANES, 1999-2008)

11. CVD Prevention Policy Model
Eligibility for Treatment:
 Based on National
Clinical Guidelines:
• ATP III for lipids
• JNC-7 for hypertension
• USPSTF for aspirin

12. CVD Prevention Policy Model
Treatment Effects:
 Meta-analyses and
literature reviews (evidence
from major clinical trials)
• Lipid treatment with statins
lowers LDL, raises HDL
• Hypertension treatment
lowers SBP
• Aspirin treatment lowers MI
risk in men, ischemic stroke
risk in men; raises HS and GI
bleeding risk in all

13. CVD Prevention Policy Model
CVD Event Risk:
 Customized 1yr risk
equations estimated
using Framingham Heart
Study Data
• Includes original and
offspring cohorts
• About 10,000 people
• Longitudinal design from
1950-2003
• Mostly white

14. CVD Prevention Policy Model
Risk of Death:
 CVD-death risk estimated
using Framingham Heart
Study data
 Death from other causes
estimated using life tables
(net of CVD mortality)

15. CVD Prevention Policy Model
Progression of Risk Factors:
 Estimated using a two-step
process:
1) Determine if there is a
change
2) Determine size of change
 Cholesterol and BP
changes from Framingham
Heart Study data
 Changes in BMI from
BRFSS (2009)

16. CVD Prevention Policy Model
Costs:
1) Costs of disease
 First-year and ongoing costs estimated from MEPS
(1999-2008)
2) Costs of screening/monitoring
 Clinic/lab fees from National Fee Analyzer (2005)
3) Costs of treatment
 Statin and antihypertensive treatment costs from
Express Scripts Drug Trend Report (2010)

17. Simulation Results
Evaluation of USPSTF Recommendations :
Preliminary estimates (2012):
1) Screening for lipid disorders in adults
 C/E: $50,000 per QALY
 CPB: 650,000 QALYs
2) Hypertension screening for adults
 C/E: $65,000 per QALY
 CPB: 500,000 QALYs
3) Aspirin counseling for primary prevention of CVD
 C/E: $100 saved per person
 CPB: 150,000 QALYs

18. Simulation Results:
Disparities
Hypertension Reference Case, No Screening, Rates per 100k
Total Men Women White Black Hispanic Other
Myocardial
29,301 38,200 20,091 28,234 33,931 29,864 27,745
Infarction
Ischemic Stroke 18,247 17,292 19,235 17,838 20,388 18,370 17,188
Angina Pectoris 21,355 25,080 17,499 20,948 22,656 21,722 21,256
Congestive
29,381 29,404 29,357 27,684 35,004 30,892 28,656
Heart Failure
Intermittent
10,498 12,204 8,732 10,232 12,200 10,200 10,182
Claudication
CVD-related
38,055 42,758 33,187 37,293 41,653 38,167 37,133
Death
Life Expectancy 78.96 76.02 82.01 79.06 78.58 78.96 78.93

19. Conclusion
Questions/Comments?