Transcript Document

NOVEL BIOMARKERS and
CARDIOVASCULAR DISEASE
Nathan D Wong, PhD, FACC
Professor and Director
Heart Disease Prevention Program
University of California, Irvine
ATP III Assessment of CHD Risk
For persons without known CHD, other forms
of atherosclerotic disease, or diabetes:
 Count the number of risk factors:
—Cigarette smoking
—Hypertension (BP 140/90 mmHg or on
antihypertensive medication)
—Low HDL cholesterol (<40 mg/dL)†
—Family history of premature CHD


CHD in male first degree relative <55 years
CHD in female first degree relative <65 years
—Age (men 45 years; women 55 years)
 Use Framingham scoring for persons with 2 risk
factors* (or with metabolic syndrome) to
determine the absolute 10-year CHD risk.
(downloadable risk algorithms at
www.nhlbi.nih.gov)
Expert Panel on Detection, Evaluation, and Treatment of
High Blood Cholesterol in Adults. JAMA. 2001;285:2486-2497.
© 2001, Professional Postgraduate Services®
www.lipidhealth.org
ATP III Framingham Risk Scoring
http://www.nhlbi.nih.gov/guidelines/cholesterol/index.htm
Step 1: Age
Years
20-34
35-39
40-44
45-49
50-54
55-59
60-64
65-69
70-74
75-79
Assessing CHD Risk in Men
Step 4: Systolic Blood Pressure
Points
-9
-4
0
3
6
8
10
11
12
13
Step 2: Total Cholesterol
TC
Points at
at Points at
(mg/dL)
Age 20-39
70-79
<160
0
160-199
4
200-239
7
240-279
9
280
11
Step 3: HDL-Cholesterol
HDL-C
(mg/dL)
60
Points
-1
50-59
0
40-49
1
<40
2
Systolic BP
(mm Hg)
<120
120-129
130-139
140-159
160
Points at
Points
Points
if Untreated if Treated
0
0
0
1
1
2
1
2
2
3
Points at
Points
Age 40-49 Age 50-59 Age 60-69 Age
0
3
5
6
8
0
2
3
4
5
0
1
1
2
3
0
0
0
1
1
Step 5: Smoking Status
at
70-79
Nonsmoker
Smoker
Points at
Points at
Age 20-39
0
8
Step 6: Adding Up the Points
Points at
Age
Total cholesterol
HDL-cholesterol
Systolic blood pressure
Smoking status
Point total
Step 7: CHD Risk
Point Total 10-Year Risk
Risk
<0
<1%
0
1%
1
1%
2
1%
3
1%
4
1%
5
2%
6
2%
7
3%
8
4%
9
5%
10
6%
Points at
Points
Point Total 10-Year
11
12
13
14
15
16
17
8%
10%
12%
16%
20%
25%
30%
Age 40-49 Age 50-59 Age 60-69 Age
0
5
0
3
0
1
0
1
Note: Risk estimates were derived from the experience of the Framingham Heart Study,
a predominantly Caucasian population in Massachusetts, USA.
Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults.
JAMA. 2001;285:2486-2497.
© 2001, Professional Postgraduate Services®
www.lipidhealth.org
Modified approach to CHD risk assessment
 LOW RISK designated as <0.6% CHD risk per
year (<6% in 10 years)
 INTERMEDIATE RISK designated as a CHD
risk of 0.6%-2.0% per year (6-20% over 10
years)
 HIGH RISK designated as a CHD risk of >2%
per year (20% in 10 years) (CHD risk
equivalent), including those with CVD,
diabetes, and PAD
Greenland P et al. Circulation 2001; 104: 1863-7
Presentation
 Examination:
— Height: 6 ft 2 in
— Weight: 220 lb
(BMI 28 kg/m2)
— Waist
circumference: 41
in
— BP: 150/88 mm Hg
— P: 64 bpm
— RR: 12 breaths/min
 Cardiopulmonary
exam: normal
 Laboratory results:
— TC:
220 mg/dL
— HDL-C: 36 mg/dL
— LDL-C: 140 mg/dL
— TG:
220 mg/dL
— FBS:
120 mg/dL
What is WJC’s 10-year absolute risk
of fatal/nonfatal MI?
 A 12% absolute risk is derived from points
assigned in Framingham Risk Scoring to:
— Age:
6
— TC:
3
— HDL-C:
2
— SBP:
2
— Total: 13 points
In 1992 he exercised 14 minutes in a Bruce protocol exercise
stress test to 91% of his maximum predicted heart rate without
any abnormal ECG changes. He started on a statin in 2001.
But in Sept 2004, he needed urgent coronary bypass surgery.
Not all individuals with coronary
heart disease have traditional risk
factors
3 RF
9%
4 RF
1%
0 RF
19%
2 RF
28%
1 RF
43%
Khot et al. JAMA 2003
The Detection Gap in CHD
“Despite many available risk assessment
approaches, a substantial gap remains in
the detection of asymptomatic individuals
who ultimately develop CHD”
“The Framingham and European risk scores…
emphasize the classic CHD risk factors…. is
only moderately accurate for the prediction
of short- and long-term risk of manifesting
a major coronary artery event…”
Pasternak and Abrams et al. 34th Bethesda conf. JACC 2003; 41:
1855-1917
Is there clinical evidence that novel risk
markers predict future coronary events
and provide additional predictive
information beyond traditional risk
factors?
Fibrinogen and Atherosclerosis
 Promotes atherosclerosis
 Essential component of platelet aggregation
 Relates to fibrin deposited and the size of the
clot
 Increases plasma viscosity
 May also have a proinflammatory role
 Measurement of fibrinogen, incl. Test
variability, remains difficult.
 No known therapies to selectively lower
fibrinogen levels in order to test efficacy in
CHD risk reduction via clinical trials.
Fibrinogen and CHD Risk:
Epidemiologic Studies
 Recent meta-analysis of 18 studies involving 4018
CHD cases showed a relative risk of CHD of 1.8
(95% CI 1.6-2.0) comparing the highest vs lowest
tertile of fibrinogen levels (mean .35 vs. .25 g/dL)
 ARIC study in 14,477 adults aged 45-64 showed
relative risks of 1.8 in men and 1.5 in women,
attenuated to 1.5 and 1.2 after risk factor
adjustment.
 Scottish Heart Health Study of 5095 men and 4860
women showed fibrinogen to be an independent
risk factor for new events--RRs 2.2-3.4 for
coronary death and all-cause mortality.
Fibrinogen and CHD Risk Factors
 Fibrinogen levels increase with age and body
mass index, and higher cholesterol levels
 Smoking can reversibly elevated fibrinogen
levels, and cessation of smoking can lower
fibrinogen.
 Those who exercise, eat vegetarian diets, and
consume alcohol have lower levels. Exercise
may also lower fibrinogen and plasma
viscosity.
 Studies also show statin-fibrate combinations
(simvastatin-ciprofibrate) and estrogen
therapy to lower fibrinogen.
P. Ridker
CRP vs hs-CRP
 CRP is an acute-phase protein produced by the liver
in response to cytokine production (IL-6, IL-1,
tumor necrosis factor) during tissue injury,
inflammation, or infection.
 Standard CRP tests determine levels which are
increased up to 1,000-fold in response to infection
or tissue destruction, but cannot adequately assess
the normal range
 High-sensitivity CRP (hs-CRP) assays (i.e. Dade
Behring) detect levels of CRP within the normal
range, levels proven to predict future cardiovascular
events.
C-Reactive Protein:
Risk Factor or Risk Marker?
 CRP previously known to be a marker of
high risk in cardiovascular disease
 More recent data may implicate CRP as
an actual mediator of atherogenesis
 Multiple hypotheses for the mechanism
of CRP-mediated atherogenesis:
—Endothelial dysfunction via ↑ NO
synthesis
—↑LDL deposition in plaque by CRPstimulated macrophages
hs-CRP as a Risk Factor For Future CVD :
Primary Prevention Cohorts
Kuller MRFIT 1996
CHD Death
Ridker PHS 1997
MI
Ridker PHS 1997
Stroke
Tracy CHS/RHPP 1997
CHD
Ridker PHS 1998,2001
PAD
Ridker WHS 1998,2000,2002
CVD
Koenig MONICA 1999 CHD
Roivainen HELSINKI 2000
CHD
Mendall CAERPHILLY 2000
CHD
Danesh BRHS 2000
CHD
Gussekloo LEIDEN 2001
Fatal Stroke
Lowe SPEEDWELL 2001
CHD
Packard WOSCOPS 2001
CV Events*
Ridker AFCAPS 2001
CV Events*
Rost FHS 2001
Stroke
Pradhan WHI 2002
MI,CVD death
Albert PHS 2002
Sudden Death
Sakkinen HHS 2002
MI
0
Ridker PM. Circulation 2003;107:363-9
1.0
2.0
3.0
4.0
5.0
Relative Risk (upper vs lower quartile)
6.0
hs-CRP Adds to Predictive Value of TC:HDL
Ratio in Determining Risk of First MI
Relative Risk
5.0
4.0
3.0
2.0
1.0
0.0
High
Medium
High
Medium
Low
Total Cholesterol:HDL Ratio
Ridker et al, Circulation. 1998;97:2007–2011.
Low
Risk Factors for Future Cardiovascular
Events: WHS
Lipoprotein(a)
Homocysteine
IL-6
TC
LDLC
sICAM-1
SAA
Apo B
TC: HDLC
hs-CRP
hs-CRP + TC: HDLC
0
1.0
2.0
4.0
6.0
Relative Risk of Future Cardiovascular Events
Ridker et al, N Engl J Med. 2000;342:836-43
Is there clinical evidence that
inflammation can be modified by
preventive therapies?
Percent with CRP 0.22
mg/dL
Elevated CRP Levels in Obesity:
NHANES 1988-1994
25
20
15
10
5
0
Normal
Overweight
Visser M et al. JAMA 1999;282:2131-2135.
Obese
Effects of Weight Loss on CRP
Concentrations in Obese Healthy
Women
 83 women (mean BMI 33.8, range 28.2-43.8 kg/m2) placed
on very low fat, energy-restricted diet (6.0 MJ, 15% fat) for
12 weeks
 Baseline CRP positively associated with BMI (r=0.281,
p=0.01)
 CRP reduced by 26% (p<0.001)
 Average weight loss 7.9 kg, associated with change in CRP
 Change in CRP correlated with change in TC (r=0.240,
p=0.03) but not changes in LDL-C, HDL-C, or glucose
 At 12 weeks, CRP concentration highly correlated with TG
(r=0.287, p=0.009), but not with other lipids or glucose
Heilbronn LK et al. Arterioscler Thromb Vasc Biol
2001;21:968-970.
Effect of HRT on hs-CRP: the PEPI
Study
hs-CRP (mg/dL)
3.0
CEE + MPA cyclic
CEE + MPA
CEE
+ MP
continuous
CEE
2.0
Placebo
1.0
0
12
Months
36
Cushman M et al. Circulation 1999;100:717-722.
1999 Lippincott Williams & Wilkins.
Long-Term Effect of Statin Therapy on
hs-CRP: Placebo and Pravastatin Groups
Placebo
0.25
Median hs-CRP
Concentration
(mg/dL)
0.24
0.23
-21.6%
(P=0.004)
0.22
0.21
0.20
Pravastatin
0.19
0.18
Baseline
Ridker et al, Circulation. 1999;100:230-235.
5 Years
Effect of Statin Therapy on hs-CRP Levels
at 6 Weeks
hs-CRP (mg/L)
6
*p<0.025 vs. Baseline
5
*
4
*
*
3
2
1
0
Baseline
Prava
Simva
Atorva
(40 mg/d) (20 mg/d) (10 mg/d)
Jialal I et al. Circulation 2001;103:1933-1935.
2001 Lippincott Williams & Wilkins.
AFCAPS/TEXCAPS showed statins to be effective in lowering
risk in the setting of normal LDL-C, but only when inflammation
was present
AFCAPS/TexCAPS Low LDL Subgroups
LowLDL,
LDL,Low
LowhsCRP
hsCRP
Low
[A]
LowLDL,
LDL,High
HighhsCRP
hsCRP
Low
[B]
0.50.5
StatinEffective
Effective
Statin
1.01.0
RR
2.02.0
StatinNot
NotEffective
Effective
Statin
However, while intriguing and of potential public health importance, the
observation in AFCAPS/TexCAPS that statin therapy might be effective
among those with elevated hsCRP but low cholesterol was made on a
post hoc basis. Thus, a large-scale randomized trial of statin therapy was
needed to directly test this hypotheses.
Ridker et al, New Engl J Med 2001;344:1959-65
A Randomized Trial of Rosuvastatin in the Prevention
of Cardiovascular Events Among 17,802 Apparently Healthy
Men and Women With Elevated Levels
of C-Reactive Protein (hsCRP):
The JUPITER Trial
Paul Ridker*, Eleanor Danielson, Francisco Fonseca*, Jacques Genest*,
Antonio Gotto*, John Kastelein*, Wolfgang Koenig*, Peter Libby*,
Alberto Lorenzatti*, Jean MacFadyen, Borge Nordestgaard*,
James Shepherd*, James Willerson, and Robert Glynn*
on behalf of the JUPITER Trial Study Group
An Investigator Initiated Trial Funded by AstraZeneca, USA
* These authors have received research grant support and/or consultation fees from one or more
statin manufacturers, including Astra-Zeneca. Dr Ridker is a co-inventor on patents held by the
Brigham and Women’s Hospital that relate to the use of inflammatory biomarkers in
cardiovascular disease that have been licensed to Dade-Behring and AstraZeneca.
Ridker et al NEJM 2008
Justification for the Use of statins in Prevention:
an Intervention Trial Evaluating Rosuvastatin
To investigate whether rosuvastatin 20 mg compared to
placebo would decrease the rate of first major cardiovascular
events among apparently healthy men and women with
LDL < 130 mg/dL (3.36 mmol/L) who are nonetheless
at increased vascular risk on the basis of an enhanced
inflammatory response, as determined by hsCRP > 2 mg/L.
To enroll large numbers of women and individuals of Black or
Hispanic ethnicity, groups for whom little data on primary
prevention with statin therapy exists.
JUPITER
Trial Design
JUPITER
Multi-National Randomized Double Blind Placebo Controlled Trial of
Rosuvastatin in the Prevention of Cardiovascular Events
Among Individuals With Low LDL and Elevated hsCRP
Rosuvastatin 20 mg (N=8901)
No Prior CVD or DM
Men >50, Women >60
LDL <130 mg/dL
hsCRP >2 mg/L
4-week
run-in
Placebo (N=8901)
MI
Stroke
Unstable
Angina
CVD Death
CABG/PTCA
Argentina, Belgium, Brazil, Bulgaria, Canada, Chile, Colombia, Costa Rica,
Denmark, El Salvador, Estonia, Germany, Israel, Mexico, Netherlands,
Norway, Panama, Poland, Romania, Russia, South Africa, Switzerland,
United Kingdom, Uruguay, United States, Venezuela
Ridker et al, Circulation 2003;108:2292-2297.
Ridker et al NEJM 2008
JUPITER
Baseline Blood Levels (median, interquartile range)
Rosuvastatin
(N = 8901)
Placebo
(n = 8901)
hsCRP, mg/L
4.2
(2.8 - 7.1)
4.3
(2.8 - 7.2)
LDL, mg/dL
108
(94 - 119)
108
(94 - 119)
HDL, mg/dL
49
(40 – 60)
49
(40 – 60)
Triglycerides, mg/L
118
(85 - 169)
118
(86 - 169)
Total Cholesterol, mg/dL
186
(168 - 200)
185
(169 - 199)
Glucose, mg/dL
94
(87 – 102)
94
(88 – 102)
HbA1c, %
5.7
(5.4 – 5.9)
5.7
(5.5 – 5.9)
All values are median (interquartile range).
[ Mean LDL = 104 mg/dL ]
JUPITER
Ridker et al NEJM 2008
140
60
120
50
100
80
60
40
20
LDL decrease 50 percent at 12 months
HDL (mg/dL)
LDL (mg/dL)
Effects of rosuvastatin 20 mg on LDL, HDL, TG, and hsCRP
0
20
10
HDL increase 4 percent at 12 months
140
120
4
3
2
hsCRP decrease 37 percent at 12 months
0
TG (mg/dL)
hsCRP (mg/L)
30
0
5
1
40
100
80
60
40
20
TG decrease 17 percent at 12 months
0
0
12
24
Months
36
48
0
12
24
Months
36
48
JUPITER
Ridker et al NEJM 2008
Primary Trial Endpoint : MI, Stroke, UA/Revascularization, CV Death
0.08
HR 0.56, 95% CI 0.46-0.69
P < 0.00001
Placebo 251 / 8901
0.04
0.06
- 44 %
Rosuvastatin 142 / 8901
0.00
0.02
Cumulative Incidence
Number Needed to Treat (NNT5) = 25
0
1
2
4
Follow-up (years)
Number at Risk
Rosuvastatin
Placebo
3
8,901
8,901
8,631
8,621
8,412
8,353
6,540
6,508
3,893
3,872
1,958
1,963
1,353
1,333
983
955
544
534
157
174
Ridker et al NEJM 2008
JUPITER
Secondary Endpoint – All Cause Mortality
HR 0.80, 95%CI 0.67-0.97
P= 0.02
0.06
Placebo 247 / 8901
0.04
0.03
0.02
Rosuvastatin 198 / 8901
0.00
0.01
Cumulative Incidence
0.05
- 20 %
0
Number at Risk
Rosuvastatin 8,901
Placebo
8,901
1
2
3
4
Follow-up (years)
8,847
8,852
8,787
8,775
6,999
6,987
4,312
4,319
2,268
2,295
1,602
1,614
1,192
1,196
683
684
227
246
JUPITER
Ridker et al NEJM 2008
Implications for Primary Prevention
A simple evidence based approach to statin therapy for
primary prevention.
Among men and women age 50 or over :
If diabetic, treat
If LDLC > 160 mg/dL, treat
If hsCRP > 2 mg/L, treat
AHA / CDC Scientific Statement
Markers of Inflammation and Cardiovascular Disease:
Applications to Clinical and Public Health Practice
Circulation January 28, 2003
“Measurement of hs-CRP is an independent marker of risk
and may be used at the discretion of the physician as part
of global coronary risk assessment in adults without known
cardiovascular disease. Weight of evidence favors use
particularly among those judged at intermediate risk by
global risk assessment”.
Clinical Application of hs-CRP for
Cardiovascular Risk Prediction
1 mg/L
Low
Risk
3 mg/L
Moderate
Risk
Ridker PM. Circulation 2003;107:363-9
10 mg/L
High
Risk
>100 mg/L
Acute Phase Response
Ignore Value, Repeat Test in 3 weeks
CRP Improves Net Reclassification Index
 From the Physicians Health Study: hs CRP and parental
history improved risk prediction 5.3% overall and 14.2% for
patients at intermediate risk by traditional risk scores (both
P<0.001) (Ridker et al., Circulation 2008)
 Framingham Heart Study: hs-CRP improved prediction of
cardiovascular disease by 5.6% (P=0.014) and of coronary
heart disease by 11.8% (P=0.009) (Wilson et al. Circulation:
Cardiovascular Quality and Outcomes 2008).
Homocysteine
 Intermediary amino acid formed by the
conversion of methionine to cysteine
 Moderate hyperhomocysteinemia occurs in 57% of the population
 Recognized as an independent risk factor for
the development of atherosclerotic vascular
disease and venous thrombosis
 Can result from genetic defects, drugs,
vitamin deficiencies, or smoking
Homocysteine
 Homocysteine implicated directly in vascular
injury including:
—Intimal thickening
—Disruption of elastic lamina
—Smooth muscle hypertrophy
—Platelet aggregation
 Vascular injury induced by leukocyte
recruitment, foam cell formation, and
inhibition of NO synthesis
Homocysteine
 Elevated levels appear to be an independent
risk factor, though less important than the
classic CV risk factors
 Screening recommended in patients with
premature CV disease (or unexplained DVT)
and absence of other risk factors
 Treatment includes supplementation with
folate, B6 and B12
Current Biomarkers for ACS
 Biomarker assessment of high risk patients may
include:
— Inflammatory cytokines
— Cellular adhesion molecules
— Acute-phase reactants
— Plaque destabilization and rupture biomarkers
— Biomarkers of ischemia
— Biomarkers of myocardial stretch (BNP)
— Biomarkers of myocardial necrosis (Troponin,
CK-MB, Myoglobin)
Apple Clinical Chemistry March 2005
Progression of Biomarkers in ACS
STABLE CAD
MPO
CRP
IL-6
PLAQUE RUPTURE
MPO
ICAM
sCD40L
PAPP-A
UA/NSTEMI
MPO
D-dimer
IMA
FABP
STEMI
TnI
TnT
Myoglobin
CKMB
Inflammation has been linked to the development of
vulnerable plaque and to plaque rupture
ACS, acute coronary syndrome; UA, unstable angina; NSTEMI, non–ST-segment elevation myocardial infarction; STEMI, ST-segment
elevation myocardial infarction
Adapted from: Apple Clinical Chemistry March 2005
Stefan Blankenberg, MD; Renate Schnabel, MD; Edith Lubos, MD, et al., Myeloperoxidase Early Indicator of Acute Coronary Syndrome and
Predictor of Future Cardiovascular Events 2005
History: Troponin
 Troponin I first described as a biomarker specific
for AMI in 19871; Troponin T in 19892
 Now the biochemical “gold standard” for the
diagnosis of acute myocardial infarction via
consensus of ESC/ACC
1
2
Am Heart J 113: 1333-44
J Mol Cell Cardiol 21: 1349-53
Troponins
 Elevated serum levels are an independent
predictor of prognosis, morbidity and mortality
 Meta-analysis of 21 studies involving ~20,000
patients with ACS revealed that those with
elevated serum troponin had 3x risk of cardiac
death or reinfarction at 30 days1
1
Am J Heart (140): 917
All-Cause Mortality by Cardiac Troponin T (n=733)
100
cTnT <0.01 g/L
80
Cumulative
survival
(%)
cTnT 0.04 g/L
60
40
cTnT 0.04
to 0.10 g/L
20
cTnT 0.10 g/L
0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Time since blood draw (years)
Patients at risk (no.) Baseline
cTnT <0.01 g/L
132
cTnT 0.01 to <0.04 g/L 214
cTnT 0.04 to <0.10 g/L 239
cTnT 0.10 g/L
148
Circulation 106:2944, 2002
1 yr
106
166
180
93
2 yr
25
41
63
20
2.5 yr
12
15
18
8
CP1090800-14
cTnT and Survival (Rancho Bernardo)
All Subjects
100
80
Survival (%)
Survival (%)
100
Subjects Without
Baseline CHD
TnT undetectable
60
40
80
TnT undetectable
60
TnT 0.01 ng/mL
40
TnT 0.01 ng/mL
P<0.001
P<0.001
20
20
0
2
4
Years
6
8
0
2
4
6
8
Years
Daniels et al: JACC 52:450, 2008
CP1322078-9
BNP
 BNP has also shown utility as a prognostic
marker in acute coronary syndrome
 It is associated with increased risk of death at
10 months as concentration at 40 hours postinfarct increased
 Also associated with increased risk for new or
recurrent MI
BNP as a Predictor of Risk in Asymptomatic
Adults: The Framingham Heart Study
Wang et al., NEJM 2004
Association of increasing BNP
levels and outcomes
End point
Hazard ratio for
1 SD increment
in log BNP value
p
Death
1.27
0.009
First major 1.28
CV event
0.03
HF
1.77
<0.001
Atrial
fibrillation
1.66
<0.001
Stroke or
TIA
1.53
0.002
CHD event
1.1
0.37
SD=standard deviation
Wang TJ et al. N Engl J Med 2004; 350:655-63.
B-Type Natriuretic Peptides and CVD Risk
(Circulation 2009; 120: 2177-2187)
 Meta-analysis of 40 long-term prospective studies
involving 87,474 patients.
 Highest vs. lowest tertile, adjusted RR=2.82 (2.403.33).
 RRs similar for BNP (2.89) or NT-pro BNP (2.82) and in
general populations (2.68), increased risk factors
(3.35), and stable CVD (2.60).
 Modest improvements in risk discrimination (increase in
C-statistic of 0.01 to 0.1).
Conjoint Effects of cTnT and NT-proBNP on
Prognosis (Rancho Bernardo)
All Subjects
100
Subjects Without
Baseline CHD
100
Low NT-proBNP
(n=667)
80
60
Survival (%)
Survival (%)
Low NT-proBNP
(n=758)
High NT-proBNP,
low TnT (n=171)
High NT-proBNP,
high TnT (n=27)
40
80
60
High NT-proBNP,
low TnT (n=122)
40
High NT-proBNP,
high TnT (n=16)
20
P<0.001 for all comparisons
0
2
4
Years
6
P<0.001 for all comparisons
20
8
0
2
4
6
8
Years
Daniels et al: JACC 52:450, 2008
CP1322078-12
Myeloperoxidase
 MPO is an enzyme that aids white blood cells
in destroying bacteria and viral particles
 MPO catalyzes the conversion of hydrogen
peroxide and chloride ions (Cl-) into
hypochlorous acid
 Hypochlorous acid is 50 times more potent in
microbial killing than hydrogen peroxide
 MPO is released in response to infection and
inflammation
 EPIC Norfolk Study showed its predictive
value for future cardiovascular disease events
in asymptomatic adults.
Sugiyama Am J Pathology 2001
Summary of MPO and ACS
 MPO leads to oxidized LDL cholesterol
— Oxidized LDL is phagocytosed by
macrophages producing foam cells*
 MPO leads to the consumption of nitric oxide
— Vasoconstriction and endothelial
dysfunction
 MPO can cause endothelial denuding and
superficial platelet aggregation
 MPO indicates activated immune cells
— Activated immune cells and inflammation
lead to unstable plaque*
 Inflammatory plaque is inherently less stable
— Thin fibrous cap/fissured/denuded
Brennan, NEJM 2003
*Hansson, NEJM 2005
MPO and MI in Asymptomatic
Subjects: EPIC-NORFOLK
Death or MI (%)
20
15
1st tertile
2nd tertile
3rd tertile
10
5
0
24 hours
72 hours
Tertile 1 MPO < 222 ug/L
Tertile 2 MPO 222 – 350 ug/L
Tertile 3 MPO > 350 ug/L
Baldus, et al. Circulation 2003;108: 1440-5.
30 days
6 months
Figure 2
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
MPO and CVD Event Risk (%)
4.9
4.3
2.5
2.2
MPO Quartile
1st
2nd
3rd
4th
P-trend = 0.05 (Wong et al. JACC Cardiovasc Img 2009 )
Figure 3
CVD Events (%)
Combined MPO-CAC Groups and CVD Event
Risk (%)
14.0%
12.0%
10.0%
8.0%
6.0%
4.0%
2.0%
0.0%
14.0%
7.1%
CAC>=100
3.2%
0.3%
MPO<257pm
3.9%
0.9%
CAC 10-99
CAC 0-9
MPO>=257pm
Log-rank test for trend P<0.0001; Wong et al., JACC Cardiovasc Img
2009
The Future of Cardiac Biomarkers
 Many experts are advocating the move
towards a multimarker strategy for the
purposes of diagnosis, prognosis, and
treatment design
 As the pathophysiology of ACS is
heterogeneous, so must be the diagnostic
strategies
A Multimarker Approach Should Focus
on Multiple Mechanisms / Pathologies
Circulation 108: 250-252
An Integrated Strategy
Multiple
Biomarkers
Intermediate Risk
Non-redundant
pathobiology
Low Risk
Potential Components of a
“Multimarker” Approach
Daniels LB. Curr CV Risk Rep 2009.
Multiple Biomarkers for Prediction of CV
Death in Older Adults
Variables
C statistic
P value
Established risk factors
0.66
Ref
+ cTnI
0.72
0.002
+ NT-proBNP
0.75
<0.001
+ cystatin C
0.69
0.07
+ CRP
0.69
0.07
+ all biomarkers
0.77
<0.001
Zethelius B et al. N Engl J Med 2008;358:2107-
Malmö, Sweden
Population-based cohort free of CVD at baseline (n=4483, mean age
58)
 5 biomarkers assessed in backward elimination
models
— CRP, cystatin C, LP-PLA2, MR-proADM, MR-proANP, NT-proBNP
 Results:
 2 markers retained for CVD events
—NT-proBNP and CRP
 2 markers retained for CHD events
—NT-proBNP and MR-proADM
Melander et al. JAMA 2009.
Malmö, Sweden
Quartiles of Multimarker Score and Risk of CV Events
HR 1.6 vs 1st Q
P=0.001 for trend
HR 1.4 vs 1st Q
HR 1.1 vs 1st Q
Multimarker score: standardized values for each marker (# of SD units from
the mean) summed, then pts divided into quartiles.
CRP, cystatin C, LP-PLA2, MR-proADM, MR-proANP, NT-proBNP
Melander et al. JAMA 2009.
Malmö, Sweden
Multiple Biomarkers and Incident CV Events
HR per 1-SD increase in BM
C-statistic without BMs: 0.758 for CVD, 0.760 for CHD
 NRI is not significant
 In intermediate risk individuals: NRI 7% (CVD) and 15%
(CHD), both significant
Melander et al. JAMA 2009.
Additional Utility of Multiple Biomarkers for Prediction of Death: FHS
ROC Curves for Death
Adj HR Death per
1 SD
BNP
1.40
CRP
1.39
Urine Alb/Cr
1.22
Homocysteine
1.20
Renin
1.17
SCORE
4.08*
0.82
Sensitivity
Biomarker
0.80
* HR for highest quintile v. lowest 2 quintiles
1-Specificity
Wang TJ et al. NEJM 2006;355:2631
Multiple biomarkers and
reclassification
Standard
risk factors
alone
Standard risk factors
plus multimarker score
<10%
10-20%
>20%
<10%
79%
3%
0%
10-20%
3%
9%
1%
>20%
0%
1%
3%
Blankenberg, S. et al. Circulation 2010;121:2388-2397
Blankenberg,
S. et al.
Circulation
2010;121:2388-2397
Copyright ©2010 American
Heart
Association
Fully adjusted HRs of biomarkers for incident cardiovascular events
Only hs-CRP,
NT-pro-BNP
and Troponin I
levels
consistently
predicted risk
of CVD events
Blankenberg,
S. et al.
Circulation
2010;121:2388-2397
Copyright ©2010 American
Heart
Association
Results of the biomarker score including troponin I, NTbroBNP, and C-reactive protein in the Belfast PRIME Men
validation cohort
Blankenberg, S. et al. Circulation 2010;121:2388-2397
Changing Targets for
Biomarkers and Imaging?
ASA +
LDL <70
High
Risk
ASA +
Statin +
Intermediate
Risk
CAC ≥ 100
↑ biomarker
No ASA
No Statin
CAC ≥ 300
Elevated Biomarker
ASA +
LDL <100
Low Risk
Budoff et al Circ 2006;114:1761-1791
Greenland et al Circ 2007;115:402-426
Multimarker Panel and CAC
ESAM ≥95%, PGLYRP-1 ≥95%, sRAGE ≤5%
CRP ≥95%, OPG ≥95%,NT-proBNP ≥95%,
0
N per Group
Adjusted OR
1
2
>3
Number of Markers
1951
419
71
38
REF
1.9
3.8
5.1
DeLemos, AHA Epi and Prevention Conf., 2010
Comparing Model Performance of
Predicting CAC Score > 10
C index
Likelihood
χ2
BIC
AIC
FRS
0.731*
373
2209
2180
FRS +
Biomarker
Score
0.760*
414
2191
2145
BIC=Bayesian Information criterion (lower indicates better model selection)
FRS=Framingham Risk Categories
* p < 0.0001 for comparison
DeLemos, AHA Epi and Prevention Conf., 2010
Total Biomarker Quartile vs.
CAC and TAC Prevalence (n=1302) (Wong ND et al., AHA Epi
2010)
80
70
60
48
52 53
64
59
68
70
57
45
50
Prevalence
40
(%)
30
33
50
39
20
10
0
CAC
TAC
CAC +/- TAC
Biomarker Quartile
Q1
P-trend =0.007 for CAC
and <0.0001 for TAC
and =0.0001 for CAC
+/- TAC
Q2
Q3
Q4
Biomarkers include high sensitivity C-reactive protein
(hs-CRP), interleukin-6 (IL-6), brain natriuretic peptide
(BNP), myleoperoxidase (MPO), plasminogen activator
inhibitor-1 (PAI-1) and angiotensinogen
Adjusted Logistic Regression of Total Biomarker Quartile with
CAC, TAC, and CAC+/-TAC (n=1302)
Biomarker Index
Quartile
CAC
TAC
CAC +/- TAC
Biomarker Index
(Continuous)
1.06*
1.04
1.07*
1st (referent)
1.0
1.0
1.0
2nd
1.22
1.19
1.41
3rd
1.22
1.17
1.42
4th
1.65**
1.31
1.52*
Wong ND et al., AHA Epi 2010
* p<0.05, ** p<0.01 compared to referent
Cumulative CV Event-Free Survival
Coronary Artery Calcium
EISNER Study: n=2458 asx adult outpatients
1.0
0.8
0.6
BNP<100 pg/mL and CAC<400
BNP≥100 pg/mL or CAC≥400
HR=5.85 (2.92-11.72)
0.4
0.2
0.0
BNP≥100 pg/mL and CAC≥400
HR=13.11 (3.97-43.34)
p<0.0001
0
1
2
3
4
5
Time (Years)
p<0.0001 in risk-adjusted model containing Framingham risk score
Shaw L, Wong ND, et al. Am J Cardiol 2009.
Risk of CVD by Combined MPO and CAC Group
AUC
RFs alone
0.755
RFs + MPO + CAC 0.838; p<0.01
RFs + CAC
0.833; p<0.01
RFs + MPO
0.762; p=NS
N=1302 asx adults – EISNER study
Wong ND, et al. iJACC 2009.
Risk Factor-Adjusted Cox Proportional Hazards Regression of Total Biomarker
Index with CHD and CVD Events (n=1302) (Wong et al., WCC 2010)
CAC - Biomarker Index Quartile
CHD Events
CVD Events
CAC 0-9 / Biomarker Index < Median (ref)
1.0
1.0
CAC 0-9 / Biomarker Index >=Median
1.0
1.0
CAC 1-99 / Biomarker Index < Median
1.3 (0.1-13)
3.8 (0.9-15)
CAC 1-99 / Biomarker Index >=Median
9.2 (2.2-38)**
6.2 (1.7-23)**
CAC 100+ / Biomarker Index<Median
19.3 (5.2-71)**
13.8 (4.3-44)**
CAC 100+ / Biomarker Index >=Median
20.1 (5.4-75)**
14.9 (4.7-48)**
* p<0.05, ** p<0.01 compared to referent
Analyses adjusted for age, gender, total and HDL-cholesterol,
diabetes, smoking, and systolic and diastolic blood pressure.
Conclusions
 Standard risk factors alone or in combination do not predict
global risk well enough
 Too
many events in too many lower risk
individuals
 Modest screening performance
 Measurement of certain biomarkers such as hs-CRP may be
useful in conjunction with global risk assessment to improve
risk classification.
 Insufficient data at the present time to recommend novel
biomarkers to screen the population at large, but selected
intermediate risk populations may be appropriate.
Conclusions (cont.)
 Individual biomarkers do not markedly improve risk
prediction
—Markers of existing disease most promising
(including imaging tools)
 Combining individual markers that reflect distinct biological
pathways is a promising strategy, with several caveats
—Combining multiple mediocre markers will not
work
—Not close to ready for clinical application
 Cost-effectiveness and outcome studies needed