Table 3

Incidence rates for VTE (definite and probable) based on 4320 women and 32,508 WY of observation (1993 – 2003). Tabulation by parameters considered as potential VTE risk factors. Descriptive tabulation of events per 10,000 WY in the exposed and non-exposed group. Incidence rate ratio (IR) and 95% confidence interval (95% CI). "Exposed" was defined as the group where the risk was assumed to be higher.

Exposed

Non-exposed

Overall

Exp. vs. Non-exposed

Exposed vs. non-exposed

WY

VTE incidence per 10⁴ WY

WY

VTE incidence per 10⁴ WY

WY

VTE incidence per 10⁴ WY

IR (95% CI)

Demographic data

Age: 30+ years vs. <30

12,346

17.0

20,162

6.5

32,508

10.5

2.6 (1.3–5.7)

BMI: 25+ vs. <25

8,764

17.1

23,696

8.0

32,460

10.5

2.1 (1.01–4.4)

OC use: ever vs never

30,388

10.5

2,116

9.5

32,504

10.5

1.1 (0.3–9.6)

Other hormones: ever vs. never

2,484

12.1

29,896

10.4

32,380

10.5

1.2 (0.2–3.7)

Smoking: yes, ever

16,878

10.7

15,615

10.2

32,493

10.5

1.04 (0.5–2.2)

Medical history

Personal history of VTE: yes

318

125.8

32,190

9.3

32,508

10.5

13.5 (3.5–38.3)

Family history of VTE: yes

3,810

26.3

28,698

8.4

32,508

10,5

3.1 (1.3–6.8)

Family history of varicous veins: yes

14,764

15.6

17,744

6,2

32,508

10.5

2.5 (1.2–5.7)

Family history of MI: yes

3,919

20.4

28,589

9,1

32,508

10.5

2.2 (0.9–5.1)

Family history of stroke: yes

2,480

20.2

30,028

9,6

32,508

10.5

2.1 (0.6–5.5)

Laboratory & genetic markers

FVL mutation^§: yes

2,105

19.0

30,308

9.6

32,413

10.2

2.0 (0.5–5.7)

Prothrombin mutation^§: yes

1,010

19.8

30,817

9.4

31,827

9.7

2.1 (0.24–8.3)

Protein C deficiency^#: yes

1510

26.5

30,958

9.7

32,468

10.5

2.7 (0.7–7.8)

AT deficiency^#: yes

1648

6.1

30,828

10.7

32,476

10.5

0.6 (0.01–3.4)

MTHFR^§: yes

18,423

9.2

13,404

10.4

31,827

9.7

0.9 (0.4–1.9)

^§ homo- and heterozygote together

^# definition see methods

Spannagl et al. Thrombosis Journal 2005 3:8   doi:10.1186/1477-9560-3-8