Clopidogrel Use and Death/MI After Stent Implantation in a

Diabetic Population

Somjot S. Brar, Simerjeet K. Brar, John Kim,

Ray Zadegan, Michael Ree, In-lu A. Liu, Prakash Mansukhani,

Vicken Aharonian, Ric Hyett, Albert Y-J. Shen

Department of CardiologyKaiser Permanente, Los Angeles

&UCLA School of Medicine Kaiser

Permanente

Results from the SUNSET registry

SCAI ‘07

Disclosures

• Research grant support from Boston Scientific– S. Brar, MD– A. Shen, MD

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Background

Death / MI reportedly increased with DES compared to BMS.

Two prior landmark analysis show increased death / MI in DES compared to BMS. BASKET-LATE Eisenstein et al.

Limited data in patients with diabetes. Duration of clopidogrel after PCI remains

unknown.

Study Questions

Is death / MI influenced by: Clopidogrel duration? Stent type (DES, BMS)?

Among patients taking clopidogrel for ≤ 6 months, is death / MI more frequent with DES compared to BMS?

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Methods

• Study date: January 2002 – December 2005• Study type: observational using the SUNSET

registry• Population:

– consecutive diabetic patients undergoing first PCI– No prior PCI or CABG – Multiple stent types not permitted– Insured members of a prepaid integrated health plan

• Location: high volume tertiary care referral center (Los Angeles, CA)

• Main outcome measure: death or MI at 18 months (545 days) post PCI

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Methods

• Clopidogrel – pharmacy prescription records– Duration of clopidogrel calculated from index PCI– User: >6 months of clopidogrel use from index PCI

date– Non-users: ≤6 months of use from the index PCI date

• “Landmark” analysis– Excluded patients with events within first 6 months– Similar to an observational analysis from BASKET-

LATE.

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Study Flow

749 diabetics underwent first revascularization

671 event free from Death or MI at 6 months

Exclusion: 41 Death/MI/Revascularization 37 Clopidogrel usage unknown

F/U to 18 months post PCI

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DES (n=450)

Four Study Groups: Stratified by Stent Type & Clopidogrel

671 Patients

Clopidogrel / Stent type

Clopidogrel (-)N=74

Clopidogrel (+)N=147

Clopidogrel (-)N=127

Clopidogrel (+)N=323

Death or MI (18 months)

BMS (n=221)

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Baseline CharacteristicsClopidogrel User Clopidogrel Non-user

DES BMS DES BMS

Age 61.5 ± 10.2 64.3 ± 10.2 63.3 ± 12.1 64.0 ± 11.6

Female 30.1% 29.9% 33.9% 36.5%

Insulin 20.7% 20.4% 31.5% 27.0%

HgA1c 7.4 ± 1.7 7.6 ± 1.8 7.3 ± 1.6 7.6 ± 1.9

LDL 114 ± 37 122 ± 39 103 ± 36 111 ± 41

Creatinine 1.2 ± 1.1 1.1 ± 0.7 1.3 ± 1.3 1.3 ± 1.6

Hemoglobin 13.5 ± 1.7 13.3 ± 1.7 13.3 ± 2.0 13.0 ± 1.7

Ejection fraction 0.61 ± 0.15 0.63 ± 0.15 0.62 ± 0.15 0.59 ± 0.16

BMI 30.7 ± 6.2 30.0 ± 5.9 30.1 ± 5.8 29.4 ± 5.9

Clopidogrel

dur. >6 mo 71.8% 66.5%

dur. >9mo 55.3% 48.9%

dur >12mo 22.9% 21.3%

Baseline CharacteristicsClopidogrel User Clopidogrel Non-user

DES BMS DES BMS

Stent No. of Stents 1.4 ± 0.6 1.4 ± 0.6 1.3 ± 0.7 1.5 ± 0.7 Mean diameter (mm) 2.9 ± 0.3 3.2 ± 0.5 3.0 ± 0.3 3.0 ± 0.5 Total cumulative

stent length (mm)26.9 ± 13.4 20.1 ± 10.2 25.1 ± 14.0 21.8 ± 9.9

Stent Location

LAD 50.5% 42.2% 44.9% 41.9%

Diagonal 4.0% 2.7% 1.6% 0%

Circumflex 16.4% 20.4% 19.7% 18.9%

Obtuse marginal 9.9% 10.2% 8.7% 12.2%

RCA 28.8% 35.4% 30.7% 31.1%

PDA / PLV 3.1% 2.7% 3.9% 8.1%

Ramus 0.9% 0% 2.4% 1.4%

Death / MI by Stent type(0d – 18mo)

Cu

mu

lati

ve I

nci

de

nce

(%

)

00

55

1010

1515

2020

No. at Risk

DES

BMS

498 469 459

251 237 225

320

218

p=0.05

Death / MI by Stent Type(6mo – 18mo)

0

5

Cu

mu

lati

ve I

nci

den

ce (

%) p=0.08

10

3.1%

6.2%

Death / MI in BMS group(6mo – 18mo)

0

10

20C

um

ula

tive

In

cid

ence

(%

)

3.5%

12.2%

p=0.01

Death / MI in DES group(6mo – 18mo)

0

10

20C

um

ula

tive

In

cid

ence

(%

)

2.2%

5.5%

p=0.07

Death / MI in Clopidogrel Non-Users (6mo – 18mo)

0

10

20

Cu

mu

lati

ve I

nci

den

ce (

%)

5.5%

12.2%

30

p=0.11

Death / MI by Clopidogrel Duration(6mo – 18mo)

10

20

Cu

mu

lati

ve I

nci

den

ce (

%)

2.0%

1.0%

7.3% (64% DES)

(69% DES)(71% DES)

p= 0.27 0

<9 months (n=314)9-12 months (n=207)>12 months (n=150)

p=0.0005

Discussion

• From index PCI date to 18 months, death / MI less with DES vs. BMS (p=0.05).

• Landmark Analysis– Clopidogrel use was associated with less death / MI

in both DES (p=0.07) and BMS groups (p=0.01). – Among clopidogrel non-users, death / MI less with

DES vs. BMS (p=0.11). – Death / MI less with 9-12 mo and >12 mo. of

clopidogrel use compared to ≤ 9 mo (p < 0.001).

• Clopidogrel compliance by Rx records was 95%

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Conclusion

• Extended clopidogrel use ( >6 mo) from the index PCI was associated with less death / MI in both DES and BMS groups.

• Overall trend towards less death / MI in the DES group compared to the BMS group.

• Among clopidogrel non-users, no difference in death / MI by stent type.

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