1. Cardiovascular Diseases and Internal Medicine
Risk Stratification in CVD Prevention How to Identify Cardiovascular Risk in the Office
Dr. Thomas G. Allison
Cardiovascular Diseases and Internal Medicine
Mayo Clinic
Rochester, MN

2. Clinically-Based CVD Prevention
Risk assessment for all patients
Set evidence- and guideline-based goals for specific risk factors
Lifestyle management
Pharmacologic intervention for selected risk factors in appropriate patients

3. Levels of Risk in Primary Prevention
Highest: the patient has evidence of CVD
High: the patient has high immediate risk (a probability of > 20% in the next 10 years) for having a CVD event
2 or more major risk factors
BP > 160/100
Diabetes
Cigarette smoking
LDL cholesterol > 160 mg/dL
HDL cholesterol < 35 mg/dL men, < 45 mg/dL women
Family history of premature CVD

4. Levels of Risk in Primary Prevention
Intermediate: the patient will not likely have a CVD event in the next 10 years, but has a high lifetime risk
1 major risk factor or
> 2 minor risk factors
BP /90-99 mmHg
Blood glucose mg/dL
LDL cholesterol mg/dL
HDL cholesterol mg/dL men, mg/dL women

5. Levels of Risk in Primary Prevention
Low: the patient may develop CVD at older ages without lifestyle adjustment
1 or 2 minor risk factors
Minor risk factors are generally correctable with lifestyle change
Diet change, exercise, weight loss
Very low: the patient will not likely develop CVD during his or her lifetime
No major or minor risk factors

6. What Do We Do with Risk? Highest risk patient High risk patient
Use secondary prevention guidelines to manage risk factors
Further evaluation: exercise test ± imaging or angiography
High risk patient
Treat all major risk factors pharmacologically
Provide appropriate lifestyle counseling
Exercise test

7. What Do We Do with Risk? Intermediate risk patient
Lifestyle counseling
Pharmacologic treatment of any major risk factors
Initial follow-up in 3-6 months, annually thereafter
Consider exercise test

8. Stress Testing for Risk Stratification in Primary Prevention
Look for clinical disease
Evaluate symptoms
Establish prognosis
Prior to prescribing exercise
Intermediate-high risk patients
High threshold of disease

9. What Do We Do with Risk? Low risk patient Very low risk patient
Recommend appropriate lifestyle change
Re-evaluate in 3-12 months
Very low risk patient
Reassure
Suggest additional evaluation in 3-5 years

10. Prediction of Lifetime Risk for Cardiovascular Disease by Risk Factor Burden at 50 Years of Age
Donald M. Lloyd-Jones et al
Circulation 2006;113:

11. High
Intermediate
Low
Very Low

12. Identifying Risk in the Office Step 1
Symptoms: Angina, TIA, claudication
Physical exam: bruits, AAA, diminished peripheral pulses, reduced ABI (0.90 for men and 0.85 for women), xanthomas
ECG: Q-waves, ST-T wave abnormalities, LVH

13. Angina has 3 characteristics
Feels like tightness, pressure, squeezing, or burning (not generally a sharp pain)
Starts in the center of the chest, behind or underneath the sternum (breast bone) – may radiate to the neck and jaw, around the back, down the arms (left more common than right)
Increased by physical activity, relieved by rest (or nitroglycerine)

14. Rose Angina Questionnaire
1. Do you get pain or discomfort in your chest when walking up hills, stairs or hurrying on level ground? (Yes or no) Positive = “yes”
2. If you get pain or discomfort in the chest when walking, do you usually stop? Slow down? Carry on at the same pace? (Mark the alternative best fitting) Positive = “stop” or “slow down”
3. If you stop or slow down, does the pain disappear after less than 10 minutes? Or after 10 minutes or more? (Mark the alternative best fitting) Positive = “after less than 10 minutes”

15. Other symptoms that might represent coronary heart disease include
Fatigue
Reduced exercise tolerance
Shortness of breath
Symptoms suggesting other vascular disease
TIA
Claudication

16. Assessing CVD Risk in the Office Step 2
Measure height, weight, waist circumference, calculate BMI
Measure blood pressure and pulse
Discuss family history of premature CVD
Review lifestyle: smoking, physical activity, diet (servings of fruits/vegetables per day)

17. Non-Fasting Blood Sugar, Lipids
Physicians in developing countries (or in low income populations in developed countries) may not have the luxury of scheduled visits for measurement of fasting blood sugar and lipids
Inexpensive, fingertip, glucometer
Opportunities for measuring these factors in non-fasting states will present

18. Non-Fasting Blood Sugar
In routine cases where patient is not fasting but not acutely ill, FBG > 150 mg/dL may serve to identify patients with diabetes or impaired fasting glucose
Consider measuring hemoglobin A1C
Reflects status prior to acute illness
May underestimate prevalence of diabetes
Elevated A1c indicates need to begin therapy

19. When to Add a Lipid Profile Step 3
Positive family history of CVD
BMI > 28 kg/m2 or prominent waist circumference (> 102 cm men, 89 cm women)
High non-fasting glucose
Improper dietary habits
Elevated blood pressure
Cigarette smoking
Consider for all patients if resources available

20. Honduras versus US Statistics
Total expenditure on health per capita
Honduras: $241 US: $6,714
Gross national income per capita
Honduras: $3,240 US: $44,070
Total expenditure on health as % of GDP
Honduras: 7.4% US: 15.3%
World Health Statistics 2008
Financial data from 2006

21. Fasting Lipid Profile? Non-HDL Cholesterol
Easy to calculate: Total-C – HDL-C
Predicts CVD risk as well as LDL-C
Goals = LDL-C goals + 30 mg/dL
Not much affected by non-fasting samples
Can be used opportunistically

22. More Tools for Assessing CHD Risk in Asymptomatic Adults
Novel risk factors (CRP, Lp(a), Lp-PLA2, etc.)
Advanced lipid testing
LDL particle concentrations, apolipoproteins
Non-invasive imaging
EBCT, CIMT, CTA, MRI
Arterial function studies
Brachial reactivity, ENDO-PAT, arterial stiffness

23. Framingham Risk Score

24. Framingham Risk Score Very age dependent
Short-term (10-year) risk projections
Ignores many factors that likely contribute to cardiovascular risk
Developed in USA with people of (western) European descent
Does it have to be modified for developing nations or different racial or ethnic groups?

25. Framingham 10-year risk by age for a male or female ● smokes 1 ppd
● TC = 212 (5.5), HDL-C = 42 (1.1)
● No DM, normal BP

26. Three Options for Preventing CVD in Asymptomatic Individuals
Wait until the patient has had a CVD event
Wait until the patient has signs of atherosclerosis
Requires expensive imaging procedures
Treat factors that lead to an increased lifetime risk of CV disease
How do we know when it is time to start?
Likely years earlier than current practice

27. Rochester, MN early fall

28. Comments?
Questions?