New targets and treatments: Understanding LDL‐P, Non‐HDL‐C, and ApoB

Samia Mora, MD, MHS

Associate Physician, BWH Heart and Vascular Center; Assistant Professor of Medicine, Harvard Medical School  www.brighamandwomens.org/heart 

Disclosures

•Consultant:

Cerenis, Lilly, Pfizer

•Institutional research grants:Atherotech DiagnosticsQuest Diagnostics (in kind)

– What are the clinically important lipids or lipoproteins for CVD risk?

– LDL-C, non-HDL-C, Total/HDL-C– LDL-P, apoB

– Are small LDL more atherogenic than large LDL particles?

– Residual risk on statin therapy

Topics to be covered

LDL cholesterol

Non-HDL chol

Total / HDL chol

Woman A

130 mg/dL

162 mg/dL

3.1

Woman B

130 mg/dL

181 mg/dL

5.3

Which woman is

at higher risk?

Mora, Circ 2009;119:2396

Woman A

130 mg/dL

162 mg/dL

3.1

22.1 nm (large)

1011 nmol/L

712 nmol/L

299 nmol/L

106 mg/dL

Woman B

130 mg/dL

181 mg/dL

5.3

20.4 nm (small)

1723 nmol/L

360 nmol/L

1286 nmol/L

127 mg/dL

Fewer Particles More Particles

Which woman is

at higher risk?

Mora, Circ 2009;119:2396

LDL cholesterol

Non-HDL chol

Total / HDL chol

LDL size (NMR)

LDL particle number (LDL-P, NMR)

Large LDL-P

Small LDL-P

ApoB

LDLCholesterol

LDL-C 130 mg/dL LDL-C 130 mg/dL

Larger

LDL Size

Smaller

LDL Size

LDL cholesterol

Non-HDL chol

Total / HDL chol

LDL size (NMR)

LDL particle number (LDL-P, NMR)

Large LDL-P

Small LDL-P

ApoB

Woman A

130 mg/dL

162 mg/dL

3.1

22.1 nm (large)

1011 nmol/L

712 nmol/L

299 nmol/L

106 mg/dL

Woman B

130 mg/dL

181 mg/dL

5.3

20.4 nm (small)

1723 nmol/L

360 nmol/L

1286 nmol/L

127 mg/dL

Fewer Particles More Particles

Which woman is

at higher risk?

Mora, Circ 2009;119:2396

– What are the clinically important lipids or lipoproteins for CVD risk?

– LDL-C, non-HDL-C, Total/HDL-C– LDL-P, apoB

– Are small LDL more atherogenic than large LDL particles?

– Residual risk on statin therapy

Topics to be covered

1

1.4

1.8

2.2

2.6

3

LDL-C Non-HDL-C Total / HDL-C

Q1 Q2 Q3 Q4 Q5

Rel

ativ

e R

isk

ofC

ardi

ovas

cula

r Eve

nts

Women’s Health Study (N=27,673)

Relative risk adjusted for age, smk, menopause, hormone use, BP, BMI, diabetes

Total/HDL-C or Non-HDL-C better than LDL-C for incident CVD

Mora et al, Circulation 2009;119:931

* All P <0.0001

*

*

*

1

1.4

1.8

2.2

2.6

3

LDL-C Non-HDL-C Total / HDL-C ApoB LDL-P (NMR)

Q1 Q2 Q3 Q4 Q5

Rel

ativ

e R

isk

ofC

ardi

ovas

cula

r Eve

nts

Mora et al, Circulation 2009;119:931

* All P <0.0001

Relative risk adjusted for age, smk, menopause, hormone use, BP, BMI, diabetes

ApoB and LDL-PNMR similar to Total/HDL-C or Non-HDL-C

Women’s Health Study (N=27,673)

*

*

**

*

Women’s Health Study

Little improvement in CVD risk classification with adding apoB or LDL-PNMR to total/HDL-C

Mora et al, Circulation 2009;119:931

C-Index NRI (p-value)† % reclassified

Total / HDL-C* 0.784 Ref. Ref.

plus LDL-P 0.785 0 (0.52) 1.1

plus ApoB 0.786 1.9 (0.02) 2.6

* Total/HDL-C plus standard CVD risk factors

† NRI: net reclassification index, which compares the proportion moving up or downclinical categories in cases or controls, comparing models that added LDL-P or apoB to a model with total/HDL-C ratio and standard CVD risk factors

0.5 1.0 1.2 1.4 1.8

Total Chol

Non-HDL-C

Total / HDL-C

ApoB

1.22 (1.17-1.27)

1.27 (1.22-1.33)

1.32 (1.24-1.39)

1.24 (1.19-1.29)

Hazard Ratio (95%CI)

Emerging Risk Factors Collaboration

26 Prospective Studies (N=139,581)

Hazard Ratio (95%CI) per 1-SD higher usual values

Adjusted for age, sex, smoking, BP, and diabetes

ERFC, JAMA 2012;307:2499-2506

Emerging Risk Factors Collaboration

No improvement in CVD risk classification with adding apoB to total/HDL-C

C-Index NRI (p-value)† % reclassified

Total / HDL-C* 0.724 Ref. Ref.

plus ApoB 0.725 - 0.2 (0.34) --

plus ApoB/A-I 0.725 0.1 (0.40) 1.1

* Total/HDL-C plus standard CVD risk factors

† NRI: net reclassification index, which compares the proportion moving up or downclinical categories in cases or controls, comparing models that added apoB to a model with total/HDL-C ratio and standard CVD risk factors

ERFC, JAMA 2012;307:2499-2506

Potential clinical utility of advanced lipid testing in certain subgroups

• Diagnosing certain dyslipidemias (eg. familial dysbetalipoproteinemia or Type III)

• Individuals whose LDL-C level is discordant (inconsistent) with LDL particle measures (eg. ApoB, LDL-P)– LDL-C low but ApoB or LDL-P high– LDL-C high but ApoB or LDL-P low

LDL-C and NHDL-C

Concordant

88

12

Discordant

Concordant

19

81

Discordant

Concordant

24

76

Discordant

Concordant

%

%

%

%

%

%

LDL-C and LDL-PNMR

LDL-C and ApoB

r = 0.91

Mora S et al, Circulation 2014; 129:553-61

LDL-P < Median (Concordant)

Discordant LDL-C and LDL particle measures?

010

0020

0030

0040

00LD

L-P

, nm

ol/L

0 100 200 300 400LDL-C, mg/dL

010

020

030

040

0N

HD

L-C

, mg/

dL

0 100 200 300 400LDL-C, mg/dL

010

020

030

040

0A

poB

, mg/

dL

0 100 200 300 400LDL-C, mg/dL

Discordant

Discordant Concordant

Concordant

Discordant

Discordant Concordant

Concordant

Discordant

Discordant Concordant

Concordant

r = 0.91

r = 0.78

r = 0.69

Women’s Health Study(N=27,533)

LDL-C vs NHDL-C

Concordant

Concordant

LDL-C vs LDL-P

LDL-C vs ApoB

r = 0.91

0.00

0.02

0.04

0.06

0.08

0.10

Cum

ulat

ive

Prob

abili

ty o

fIn

cide

nt C

HD

2 4 6 8 10 12 14 16 18Follow-Up (Years)

Low LDL-C, High Non-HDL-CLow LDL-C, Low Non-HDL-C

0.00

0.02

0.04

0.06

0.08

0.10

Cum

ulat

ive

Prob

abili

ty o

fIn

cide

nt C

HD

2 4 6 8 10 12 14 16 18Follow-Up (Years)

Low LDL-C, High ApoBLow LDL-C, Low ApoB

0.00

0.02

0.04

0.06

0.08

0.10

Cum

ulat

ive

Prob

abili

ty o

fIn

cide

nt C

HD

2 4 6 8 10 12 14 16 18Follow-Up (Years)

Low LDL-C, High LDL-PLow LDL-C, Low LDL-P

LDL-P ≥ Median (Discordant)

LDL-P < Median (Concordant)

ApoB ≥ Median (Discordant)

ApoB < Median (Concordant)

NHDL-C ≥ Median (Discordant)

NHDL-C < Median (Concordant)

Mora et alCirc 2014; 129:553-61

NHDL-C ≥ Median (Concordant)

NHDL-C < Median (Discordant)

ApoB ≥ Median (Concordant)

ApoB < Median(Discordant)

LDL-P ≥ Median (Concordant)

LDL-P < Median (Discordant)

LDL-C < Median LDL-C ≥ Median

– What are the clinically important lipids or lipoproteins for CVD risk?

– LDL-C, non-HDL-C, Total/HDL-C– LDL-P, apoB

– Are small LDL more atherogenic than large LDL particles?

– Residual risk on statin therapy

Topics to be covered

Large LDL (Pattern A) Small LDL (Pattern B)

Carries more cholesterol per

particle

Elevated in FH

Elevated with high sat fat

Low in countries with low fat

diet (Costa Rica)

High in Native Americans,

Scotland (high CAD)

Oxidized more rapidly

Elevated in metabolic

syndrome/insulin resistance

Associated with low HDL-C,

high TG

Altered endothelial function

Altered fibrinolysis

Sacks and Campos, J Clin Endocrinol Metab 2003;88:4525-4532.

Both have reduced affinity to LDL receptorIn vivo, similar transit time across arterialintimaBoth bind arterial proteoglycans thusactivating plaque progression

Both large and small LDL share atherogenic properties:

Sacks and Campos, J Clin Endocrinol Metab 2003;88:4525-4532.

Controversy over the importance of LDL size as independent risk factor

Adjustment for other risk factors (TG, HDL) attenuated the association of LDL size to non-significant in most studies

LDL size and CVD: prior studies

Stampfer et al JAMA 1996;276:882-888.

Physicians Health Study nested case-control

Quebec Cardiovascular Study

"Among lipid, lipoprotein, and apolipoprotein variables, apo B came out as the best and only significant predictor of CHD risk in multivariate stepwise logistic analyses (P=.002).”

“[LDL size] as a continuous variable did not contribute to the risk of CHD after the contribution of apo B levels to CHD risk had been considered."

Lamarche et al Circulation 1997; 95:69-75

Most previous studies examined LDL size phenotype by GGE

Limitation of gradient gel electrophoresis(GGE): Decrease in average LDL size does not necessarily translate into greater number of small LDL particles, since it could also be due to fewer large LDL particles

Measurement of LDL size

Mora, Circ 2009;119:2396

LDL size (average)

Large LDL

Small LDL

Large LDL

Small LDL

Less LDL particles

More LDL particles

Mora, Circ 2009;119:2396

A confounder is associated with the risk factor and is causally related to the outcome

Risk factor Outcome

Confounder

Alcohol CHD

Smoking

Is the relation of LDL size with CHD confounded by LDL particle number ?

A confounder is associated with the risk factor and is causally related to the outcome

Risk factor Outcome

Confounder

LDL Size CHD

LDL-P

?

Is the relation of LDL size with CHD confounded by LDL particle number ?

Mora, Circ 2009;119:2396

Adjusting for small LDL-P unmasks the true relation of large LDL-P with IMT

MESA Study (N=5538)

920

950

980

1010

1040

Q1 Q2 Q3 Q4 Q5Large LDL-P Quintiles

Ptrend = 0.94 Ptrend <0.001

Adjusted for age and sex Adjusted for age,sex, and small LDL-P

IMT

(mic

rons

)

Mora et al, Atherosclerosis 2007;192:211-17

Relation of LDL size with IMT

IMT (SE) in m per

1-SD P value

LDL Size (unadjusted for LDL-P) -20.9 (4.5) <0.001

LDL Size (adjusted for LDL-P*) +14.5 (7.2) 0.05

Models adjusted for age, sex, race, smoking, and hypertension.

*correlation of LDL size with LDL-P = -0.64

Mora et al, Atherosclerosis 2007;192:211-17

0

0.5

1

1.5

2

2.5

Small LDL-P Large LDL-P

Q1 Q2 Q3 Q4 Q5

Rel

ativ

e R

isk

ofC

ardi

ovas

cula

r Eve

nts

Mora et al, Circulation 2009;119:931

* P <0.0001

Relative risk adjusted for age, smk, menopause, hormone use, BP, BMI, diabetes

Women’s Health Study: Small vs large LDL-PNMR

N=27,673

*

0

0.5

1

1.5

2

2.5

Small LDL-P Large LDL-P Large LDL-Padjusted forsmall LDL-P

LDL-P(Total)

Q1 Q2 Q3 Q4 Q5

Rel

ativ

e R

isk

ofC

ardi

ovas

cula

r Eve

nts

Mora et al, Circulation 2009;119:931

* P <0.0001

Relative risk adjusted for age, smk, menopause, hormone use, BP, BMI, diabetes

Both small and large LDL associated with increased CVD

N=27673

*

*

*

For type 2 diabetes, LDL particle size was strong and independent predictor

Q1 Q2 Q3 Q4 Q5 Ptrend

LDL size 4.16 3.04 2.21 1.63 1.00 <0.001

Small Large

* Relative risk adjusted for age, race, smk, menopause, HRT, BP, BMI, exercise, education, FHx, CRP, HbA1c

Mora et al, Diabetes 2010 ; 59:1153-1160

0

0.5

1

1.5

2

2.5

3

3.5

4

LDL-C Small LDL-P IDL-P LDL-P (Total) Large LDL-P

Q1 Q2 Q3 Q4 Q5

Rel

ativ

e R

isk

ofD

iabe

tes

* P <0.0001

Large LDL associated with lower risk of diabetes

Women’s Health Study (N=26,836)

*

*

**

Mora et al, Diabetes 2010 ; 59:1153-1160

Relative risk adjusted for age, race, smk, menopause, HRT, BP, BMI, exercise, education, FHx, CRP, HbA1c

Mora et al, ATVB meeting, Toronto, 2014, manuscript in preparation

JUPITERIon Mobility LDL Subclasses and CVD Risk in

placebo groupBaseline LDL-C 109 mg/dL

– What are the clinically important lipids or lipoproteins for CVD risk?

– LDL-C, non-HDL-C, Total/HDL-C– LDL-P, apoB

– Are small LDL more atherogenic than large LDL particles?

– Residual risk on statin therapy

Topics to be covered

Final model * % or SD HR (95% CI) PBMI (per 1-SD), kg/m2 4.5 1.09 (1.02, 1.17) 0.01Myocardial infarction 58 1.60 (1.36, 1.87) <0.001Angina 82 1.36 (1.10, 1.68) 0.004Cerebrovascular disease 5 1.73 (1.36, 2.19) <0.001Peripheral vascular disease 12 1.32 (1.09, 1.61) 0.005Congestive heart failure 8 1.54 (1.24, 1.90) <0.001CABG 47 1.26 (1.08, 1.47) 0.004Calcium channel blocker 27 1.31 (1.12, 1.54) <0.001Aspirin 87 0.67 (0.56, 0.81) <0.001Baseline (per 1-SD, on-statin), mg/dL

Apolipoprotein BApolipoprotein A-IBUN

19254.9

1.19 (1.11, 1.28)0.91 (0.84, 0.99)1.10 (1.03, 1.17)

<0.0010.020.003

* Final model included randomized treatment, age, sex, HTN, smk, DM plus these variables Mora S et al. Circulation, 2012:125:1979-87.

Treating to New Targets (TNT)Multivariable Predictors of Residual Risk

Lipid or Apoipoprotein SD, mg/dL HR (95% CI) * P

LDL-C 27.4 1.31 (1.09-1.56) 0.004

Non-HDL-C 30.8 1.25 (1.04-1.50) 0.02

Apo B 22.1 1.27 (1.06-1.53) 0.009

Triglycerides 62.7 0.93 (0.74-1.17) 0.56

HDL-C 16.3 0.89 (0.70-1.12) 0.29

Apo A-I 32.4 0.81 (0.65-1.01) 0.06

JUPITER:On-Treatment Lipids and Residual Risk

On-Treatment LDL-C 55 mg/dL

* Standardized hazard ratios adjusted for age, sex, smoking, BP, glucose, BMI, family history

Mora S et al., JACC 2012; 59:1521-8

Boekholdt et al JACC 2014;64:485

Achieved LDL-C

mg/dL

Large inter-individual variability in response to high-intensity statin

Meta-analysis of TNT, IDEAL, SPARCL, JUPITERN=18,661

Achieved Non-HDL-C Achieved ApoB

mg/dLmg/dL

N

Lipid or Apoipoprotein

AdjustedHR (95% CI) * P

LDL-C 1.13 (1.10-1.17) <0.001

Non-HDL-C 1.16 (1.12-1.19) <0.001

Apo B 1.14 (1.11-1.18) <0.001

Boekholdt SM et al., JAMA 2012; 307:1302-9

Meta-analysis of 8 statin trials(N=38,153; No. events=5,387)

On-Treatment Lipids and Residual Risk

Boekholdt SM et al., Circulation 2013; 128:1504-12

Differential genetic effects on statin-induced changes in LDL-C, apoB, LDL-P, LDL size

JUPITER, N=7046 Caucasians

Chu A et al, in preparation

LDL-C NHDL-C ApoB LDL-P LDL size

SNP cluster ∆ LDL size

SNP cluster ∆ LDL-P

SNP cluster ∆ ApoB

SNP cluster ∆ All

LDLCholesterol

LDL-C 130 mg/dL LDL-C 130 mg/dL

Larger

LDL Size

Smaller

LDL Size

LDL cholesterol

Non-HDL chol

Total / HDL chol

LDL size

LDL particle number (LDL-P)

Large LDL-P

Small LDL-P

ApoB

Woman A

130 mg/dL

162 mg/dL

3.1

22.1 nm (large)

1011 nmol/L

712 nmol/L

299 nmol/L

106 mg/dL

Woman B

130 mg/dL

181 mg/dL

5.3

20.4 nm (small)

1723 nmol/L

360 nmol/L

1286 nmol/L

127 mg/dL

Fewer Particles More Particles

Which woman is

at higher risk?

Mora, Circ 2009;119:2396

– What are the clinically important lipids or lipoproteins for CVD risk?

– LDL-C, non-HDL-C, Total/HDL-C– LDL-P, apoB

– Are small LDL more atherogenic than large LDL particles?

– Residual risk on statin therapy

Topics covered