HDL CHOLESTEROL REVISITED-- A RELIABLE DIAGNOSTIC TOOL OR JUST A PASSING FANCY? GARY A. LOPEZ, M.D.
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Transcript of HDL CHOLESTEROL REVISITED-- A RELIABLE DIAGNOSTIC TOOL OR JUST A PASSING FANCY? GARY A. LOPEZ, M.D.
HDL CHOLESTEROL REVISITED-- A RELIABLE DIAGNOSTIC TOOL OR
JUST A PASSING FANCY?
GARY A. LOPEZ, M.D.
Disclosures
None
Atherosclerotic Heart Disease• Continues to be the foremost cause of
mortality in the Western world and is rapidly becoming so in the developing nations
• Low-density lipoprotein (LDL) reduction using statins have been established to reduce the number of recurrent cardiovascular events and has been the main contributor of CHD reduction
• Residual events still occur despite statin treatment
Coronary Heart Disease according to HDL-C Levels: The Framingham Heart Study
CH
D R
isk
Rat
io
Kannel WB, Am J Cardiol, 1983;52:9B-12B
4.0
2.0
1.0
• For every 1 mg/dl decrease in HDL, there is a corresponding 2% increased risk of CHD in men and 3% for women (overall average = 2.5%)
(22 studies;90,000 patients)
Properties of HDL
Function• Reverse cholesterol transport (RCT)• LDL antioxidation• Endothelial protection
• Antiplatelet activity
• Anticoagulation
Mechanism• Cholesterol efflux through
ABCA1, ABCG1, ABCG4• Activation of LCAT• Inhibition of adhesion
molecule expression, prevention of monocyte chemotaxis, nitric oxide synthase stimulation
• Protection against endothelial injury
• Inhibition of factors Va and VIIa
CETP
PPAR
ACATACAT
LCAT
HDL Functionality and Reverse Cholesterol Transport
HDL Functionality and Reverse Cholesterol Transport
CE
TG
Treatment: Non-pharmacologic
• Aerobic exercise• Diet• Weight loss• Tobacco cessation• AlcoholALL MODESTLY INCREASE HDL-C
Statins• LDL-C reduction causing decrease in
atherosclerosis progression and cardiovascular events
• Increases HDL-C levels by 5-15% (ave. = 9%)• HDL-C effects relatively smaller compared to
LDL-C• Promotes formation of more favorable HDL
subfraction profile by creating more cholesterol-rich HDL particles thru reduction of cholesterol transfer from HDL
70% 69% 76% 76% 84% 76% 76% 44%Percent Residual Cardiovascular Risk
CTT Meta Analysis
CTT Meta Analysis
Low HDL-C is a Predictor of Coronary Low HDL-C is a Predictor of Coronary Events in Statin-Treated PatientsEvents in Statin-Treated Patients
Adapted from Ballantyne CM et al. Circulation 1999;99:736-743Adapted from Ballantyne CM et al. Circulation 1999;99:736-743 ..
Co
ron
ary
Ev
ents
(%
)C
oro
na
ry E
ven
ts (
%)
1.11.14242
< 0.9< 0.93535
1.351.355252
0.990.993838
1.01.0>39>39
1.01.0<39<39
1.261.264444
0.750.753333
mmol/Lmmol/Lmg/dlmg/dl
05
10152025
3035
4S LIPID CARE HPS
HDL-C (mg/dl)
Statin Placebo
Low HDL-C Increases Cardiovascular Disease Risk Even If LDL-C Levels Are Well-controlled:
The Treating to New Targets Study
0
2
4
6
8
10
Q1 Q2 Q3 Q4 Q5
5-Year Risk of Major
Cardiovascular
Disease Events (%)
HDL-C quintiles*(mg/dL)
*On-treatment level (3 months statin therapy)†Mean low-density lipoprotein cholesterol (LDL-C) level = 58 mg/dL; mean triglyceride (TG) level = 126 mg/dL‡P=.03 for differences among quintiles of HDL-C
Patients (n = 2661) with LDL-C <70 mg/dL on a Statin*†
37 to <42 42 to <47 42 to <55 >55<37
0.85 0.57 0.55 0.61Hazard Ratio vs. Q1‡
Barter P, et al. N Engl J Med. 2007;357:1301-1310.
+64%
Coronary Lesion Change with HDL-Raising Drug Treatment Using Niacin
mm
Mean change, minimum lesion diameter
BECAIT LOCAT DAIS CLAS FATS
HATS
Coronary Drug Project Long-Term Mortality Benefit of Niacin in Post-MI
Patients (8341 men)
Niacin
Placebo
P = 0.0012
100908070605040302010
0 2 4 6 8 10 12 14 16
Years of follow-up
Survival (%)
Canner PL et al. J Am Coll Cardiol 1986;8:1245–1255
Atherothrombosis Intervention in Metabolic Syndrome with Low HDL/High Triglycerides: Impact
on Global Health Outcomes (AIM-HIGH Trial)
• Patients: 3,414 M/F with vascular disease and HDL-C <40 and 50 mg/dL, respectively; TG 150–400; and LDL-C <180 mg/dL, 3–5-year follow-up
• Centers: 91 centers (~36 patients per center) in US and Canada (20%)
• Therapy: Simvastatin vs. Simvastatin + Extended-release niacin (1500-2000mg)
• Primary Endpoint: Coronary heart disease death, myocardial infarction, stroke, or high-risk acute coronary syndrome hospitalization
AIM-HIGH Trial: CHD Death, MI, Stroke, High-Risk ACS Hospitalization
Boden WE et al, New Eng J Med, 2011; 365:2255-67Boden WE et al, New Eng J Med, 2011; 365:2255-67
Atherothrombosis Intervention in Metabolic Syndrome with Low HDL/High Triglycerides: Impact
on Global Health Outcomes (AIM-HIGH Trial)
• Trial stopped 18 mos. early 5/25/11 by Data Monitoring Board
• Niacin failed to reduce CV events in 36 mos.• Ischemic strokes higher in Niacin arm (1.6% vs. 0.7%)• Primary endpoint around 16% CV events reduction in both
arms – less frequent than the expected 25%• LDL averaged below 70 in both arms at 3 years• 25% increase in HDL and 29% trig reduction in Niacin arm
Issues Regarding AIM-HIGH
• Placebo group received 50 mg Niacin and had modest 10% increase in HDL-C
• High-risk patients such as those recently hospitalized for ACS were excluded
• Few women (15%) and minorities (8%) enrolled
Fibric acid derivatives (Fibrates)
• Increases HDL-C levels by 10-15% by PPAR- activation, causing up-regulation of ABCA1 and hepatic HDL synthesis
• Main effect is to lower triglycerides by 25-45% and lower LDL-C by 10-20%
Jun M et al, Lancet ,2010; 375: 1875-84 Jun M et al, Lancet ,2010; 375: 1875-84
Thiazolidinediones
• Insulin-sensitizers (Pioglitazone,Rosiglitazone)• FDA-approved for treatment of diabetes• Noted to modestly increase HDL levels (2.7-
4.6 mg/dl)• Rosiglitazone pulled out from market;
Pioglitazone has side effect issues• With current data, generally not used
primarily for HDL modification
Background: CETP inhibition
HDLHDL
LDL / LDL / VLDLVLDL
LiverLiver
BileBile
CECE
LDL-RLDL-R
FCFC
FCFC
LCATLCAT
CETPCETP
CCEESR-B1SR-B1
X X inhibitioninhibition
Cholesteryl ester transfer protein (CETP) is a plasma protein that catalyzes the transfer of CE from HDL to apoB-containing lipoproteins (VLDL and LDL-C) in exchange for Trig.
Free Cholesterol (FC) Free Cholesterol (FC) in Extrahepatic tissuesin Extrahepatic tissues
The Investigation of Lipid Level Management to Understand Its Impact in Atherosclerotic Events
(ILLUMINATE Trial)
• 15,067 patients with history of CV disease or Type 2 DM receiving atorvastatin
• Randomly assigned to torcetrapib or placebo• Over 1 year, Torcetrapib group had : - 72.1% increase in HDL-C - 24.9% decrease in LDL-C - 9% decrease in triglycerides
ILLUMINATE Trial
5.0
1.2
HR 1.25P=0.001
HR 1.54P=0.006
%
NEJM 2007; 357:2109-22(Primary endpoint)
•May 7,2012: Trial stopped despite no safety signals due to “a lack inclinically meaningful efficacy” in the results.
Primary Endpoint: Time to first occurrenceOf CHD death, nonfatal AMI, unstable angina requiring hospitalization,resuscitated cardiac arrest or atherosclerotic stroke
Dalcetrapib : dal-OUTCOMES TrialDalcetrapib : dal-OUTCOMES Trial
Safety of Anacetrapib in Patients with or at Risk for Coronary Heart Disease
•Christopher P. Cannon, MD, Sukrut Shah, PhD, RPh, Hayes M. Dansky, MD, Michael Davidson, MD, Eliot A. Brinton, MD, Antonio M. Gotto, Jr., MD, DPhil, Michael Stepanavage, MS, Sherry Xueyu Liu, MS, Patrice Gibbons, MS, Tanya B. Ashraf, BA, Jennifer Zafarino, MS, Yale Mitchel, MD, Philip Barter, MD, PhD, for the DEFINE Investigators
DEFINE TrialCardiovascular Death, MI, Unstable Angina or Stroke
(after 24 weeks / 1623 patients)
%
Cannon CP, et al. N Engl J Med 2010;363:2406-2415
Effects on LDL-C and HDL-C
HDL-C
Study Week
BaselineWk 6Wk 12Wk 18Wk 24Wk 30 Wk 46 Wk 62 Wk 76
HD
L-C
(m
g/d
L) (
SE
)
0
20
40
60
80
100
120
AnacetrapibPlacebo
Anacetrapib n =Anacetrapib n = 776 757 718 687 647 607 572 543
Placebo n =Placebo n = 766 761 741 744 736 711 691 666
LDL-C
Study Week
BaselineWk 6Wk 12Wk 18Wk 24Wk 30 Wk 46 Wk 62 Wk 76
LDL-
C (
mg/
dL)
(SE
)
0
20
40
60
80
100
AnacetrapibPlacebo
Anacetrapib n = 804 771 716 687 646 604 568 540
Placebo n = 803 759 741 743 735 711 691 666
-39.8% (p<0.001) +138.1% (p<0.001)
•30,000 patients with occlusive arterial disease in North America, Europe and Asia•Background LDL-lowering with Atorvastatin•Randomized to Anacetrapib 100 mg vs placebo•Scheduled follow-up in 4 years•Primary outcome: coronary death, myocardial infarction or coronary revascularization
Lipid-Modulating Effects of Evacetrapib, a Novel CETP Inhibitor, Administered as
Monotherapy or in Combination with the Most-Commonly Used
Statins
SJ Nicholls, HB Brewer, JJP Kastelein,KA Krueger, MD Wang, K Wolski , E McErlean, SE Nissen
Presented at AHA Scientific Sessions, Orlando, Nov, 2011
Percent Change HDL-C: Evacetrapib 100 mg Combined with Statin Therapy
P<0.001 P,0.001 P<0.001
7.3
86.6
1.4
79.9
5.5
94
%
Evacetrapib: Conclusions
• Evacetrapib monotherapy produced a dose-dependent increase in HDL-C up to 128.8% and decrease in LDL-C up to 35.9%
• Evacetrapib was well-tolerated with no adverse blood pressure or mineralocorticoid effects
• The impact of evacetrapib on cardiovascular events remains to be determined
Summary of CETP Inhibition Trials
• The state of CETP inhibition remains strong with ongoing studies testing the hypothesis that raising HDL through CETP inhibition will be beneficial for RCT and modulation of cardiovascular disease
ACAT InhibitorsACAT Inhibitors
rHDL InfusionsA1 Milano InfusionsA1 Peptide Mimetics
A1 Up-regulators
rHDL InfusionsA1 Milano InfusionsA1 Peptide Mimetics
A1 Up-regulators
Other Therapeutic Modalities
Association of an HDL-C Genetic Variant (LIPG Ans396Ser) With Myocardial Infarction in 116,320 Participants From 20 Studies
(PROCARDIS Consortium)
Voight BF et al, Lancet,17 May, 2012
Arsenault BJ et al, Epic-Norfolk Prospective Population Study, Atherosclerosis, Sept,2009Arsenault BJ et al, Epic-Norfolk Prospective Population Study, Atherosclerosis, Sept,2009
Large HDL particle size has the most favourable CHD risk profile
Dysfunctional HDL
• HDL transformed into a pro-inflammatory and pro-oxidative state
• Inflammation plays a central role in creating dysfunctional HDL and disrupting RCT
Is Cholesterol Efflux Capacity
More Reliable Instead of
HDL Quantity?
Cholesterol withinMacrophage Foam Cells
p=0.002
Conclusion• There is overwhelming evidence that high levels of
HDL-C is associated with lower risk of coronary HD• HDL-C has evolved as one of the risk factor to
predict risk of incident Coronary HD• Lifestyle interventions are safe but only modestly
increase HDL-C• Best treatment currently are the niacin derivatives
particularly for atherogenic dyslipidemia and metabolic syndrome with high cardiometabolic risk
Conclusion (2)
• Newer agents such as CETP inhibitors hold much promise.
• Other possible points to target include: -efflux or cycling of HDL instead of HDL level -raising specific HDL subclasses instead of
HDL itself
Main Issues1. Could we accept HDL as a significant risk factor in the progression of Atherosclerotic Vascular Disease? YES2. Is HDL a reliable therapeutic target in
Atherosclerotic Vascular Disease? NO3. Can we completely disregard HDL in monitoring
lipids and simply label it as a passing fancy? NO
Thank YouThank You