Table 1 Characteristics of warfarin users under study, by antihyperlipidemic cohort.

From: Thromboembolic and neurologic sequelae of discontinuation of an antihyperlipidemic drug during ongoing warfarin therapy

 

Antihyperlipidemic of interest

atorva

ceriva*

feno

fluva*

gem

lova

pitava*

prava

rosuva

simva

Persons

219

**

24

**

11

36

**

68

22

235

Persons-days of observation period, median (Q1-Q3) per individual

112.0 (45.0–197.0)

79.5 (31.5–128.0)

98.0 (57.5–217.0)

66.0 (43.0–110.0)

43.0 (29.0–126.0)

74.5 (40.5–189.0)

17.0 (17.0–17.0)

102.0 (53.0–203.5)

109.0 (57.0–171.0)

100.0 (46.0–190.0)

Person-days of observation period, total

34,789

319

3,772

1,156

811

4,726

17

10,610

2,585

34,979

% person-days of observation period in risk segment

13.5

23.2

13.2

23.8

28.0

12.5

0.0

12.6

11.7

10.6

Outcomes during observation period

238

**

27

11

11

38

**

73

23

248

VTE

170

**

**

**

**

26

**

52

**

162

IS

68

0

**

**

**

12

0

21

**

86

Demographics

Group

% of persons (unless otherwise noted)

Age in years at start of observation period

Median (Q1-Q3)

68.9 (54.3–78.1)

80.5 (72.0–86.5)

61.3 (48.4–69.9)

66.5 (51.8–84.0)

57.3 (46.1–63.4)

72.2 (57.1–80.2)

62.5 (62.5–62.5)

71.4 (57.2–78.7)

63.8 (55.3–74.4)

71.1 (59.4–80.0)

Sex

Female

69.9

**

66.7

**

**

61.1

**

58.8

77.3

62.6

Race

White

60.3

**

79.2

**

**

55.6

0.0

60.3

**

51.9

Black

16.9

**

**

0.0

**

**

**

**

**

23.8

Hispanic/Latino

8.7

0.0

0.0

**

**

**

0.0

**

**

11.5

Other/Unknown

14.2

**

**

**

**

**

**

**

**

12.8

State of residence

California

39.3

**

**

**

**

41.7

0.0

54.4

**

29.8

Florida

14.2

**

**

**

**

**

**

17.6

**

17.9

New York

24.2

0.0

**

**

**

**

0.0

**

**

26.0

Ohio

13.2

**

**

**

**

**

**

**

**

12.3

Pennsylvania

9.1

0.0

**

**

**

**

0.0

**

**

14.0

Calendar year at start of observation period†

1999

**

**

**

**

0.0

**

0.0

**

0.0

**

2000

**

**

0.0

**

**

**

0.0

**

0.0

**

2001

10.0

**

**

**

**

**

0.0

**

0.0

5.5

2002

9.6

0.0

0.0

0.0

**

**

0.0

**

0.0

4.7

2003

7.3

0.0

**

**

0.0

**

0.0

**

0.0

4.7

2004

8.2

0.0

0.0

**

**

**

0.0

**

0.0

**

2005

10.5

0.0

**

0.0

**

**

0.0

**

**

**

2006

12.3

0.0

**

0.0

0.0

**

0.0

**

**

4.7

2007

9.1

0.0

**

**

0.0

**

0.0

**

0.0

11.5

2008

10.5

0.0

**

0.0

**

**

0.0

**

**

13.6

2009

8.7

0.0

**

0.0

**

**

0.0

**

**

14.5

2010

5.5

0.0

**

0.0

**

**

0.0

**

**

17.4

2011

**

0.0

**

0.0

0.0

**

**

**

**

14.9

Medicare enrolled at start of observation period

Yes

79.0

**

75.0

**

**

88.9

**

88.2

81.8

77.4

Nursing home resident at start of observation period

8.7

**

**

**

**

**

**

**

**

17.4

Pre-defined time-varying covariates

Group

% of person-days (unless otherwise noted)

Major non-chronic risk factor for outcome

    VTE in prior 90 days

Yes

30.3

68.0

54.9

17.9

69.2

32.2

**

30.9

38.4

28.9

    IS in prior 90 days

9.0

0.0

3.2

12.5

5.5

7.5

0.0

8.5

20.0

12.4

    Hospital discharge on current day or in prior 90 days

31.6

49.2

41.6

35.7

70.4

36.1

**

30.2

41.5

34.2

Major non-chronic disease that may affect coagulation

    Acute infection on current day or in prior 14 days

Yes

15.3

16.9

10.5

15.6

14.1

10.5

**

16.7

16.1

15.3

Drug that may affect coagulation†

    anticoagulant, oral non-warfarin

Yes

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

    anticoagulant, injectable/subcutaneous

0.9

0.0

0.0

0.0

0.0

0.0

0.0

0.8

1.2

0.5

    antiplatelet, oral

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

    aspirin

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

Drug that may interact with warfarin

    interacting drug, oral, per Truven‡

Yes

29.3

42.9

30.4

10.4

26.3

38.6

0.0

30.7

12.4

17.3

    CYP2C9 inhibitor‡

11.0

42.6

15.6

0.0

7.5

10.3

0.0

8.4

2.3

5.0

    CYP2C9 inducer†

5.8

0.0

0.0

0.0

0.0

0.6

0.0

6.1

0.0

1.6

Drug that may increase risk of VTE alone†

Yes

26.7

0.0

31.0

11.5

55.7

40.3

0.0

19.5

19.1

21.9

Drug that may increase risk of IS alone‡

Yes

24.8

42.6

30.0

3.1

9.0

25.0

0.0

19.5

13.2

23.8

Drug that may increase risk of VTE and IS†

Yes

15.9

46.1

17.7

12.8

24.7

26.2

0.0

19.1

18.8

10.2

Therapeutic drug monitoring for warfarin

Yes

32.5

41.1

31.8

27.3

29.1

28.0

0.0

31.0

31.8

31.1

Average daily warfarin dose, in milligrams

Median (Q1-Q3)

4.8 (2.5–5.0)

4.0 (4.0–4.0)

3.0 (2.0–5.0)

4.0 (2.5–5.0)

5.0 (3.7–6.0)

5.0 (2.5–5.0)

7.5 (7.5–7.5)

2.5 (1.5–5.0)

3.0 (2.0–5.0)

4.0 (2.0–5.0)

  1. Atorva = atorvastatin; CYP = cytochrome P450; feno = fenofibrate; gem = gemfibrozil; IS = ischemic stroke; lova = lovastatin; prava = pravastatin; Q = quartile; rosuva = rosuvastatin; simva = simvastatin; VTE = venous thromboembolism.
  2. *Excluded from further study because few persons in cohort.
  3. **Value suppressed to ensure subject anonymity, consistent with Centers for Medicare and Medicaid Services privacy rule for small cells; cell < 11 or would permit back-calculation of a cell < 11.
  4. †If dispensed on current day or in prior 30 days.
  5. ‡If dispensed on current day or in prior 30 days for chronically-administered drugs (14 days for acutely-administered drugs).
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