TABLE 1.

Venous Thromboembolism (VTE) Incidence Rates Over 19 Years of Follow-Up: Iowa Women's Health Study, 1986–2004

	No. of VTE Events	No. of Participants	No. of Person-Years	Rate per 1000 Person-Years
Overall	2137	40 377	529 360	4.04
Age group,a y
65–69	474	39 825	161 622	2.93
70–74	684	37 906	179 364	3.81
75–79	612	32 182	122 927	4.98
80–84	309	17 295	55 479	5.57
≥ 85	58	5 577	9 968	5.82
VTE categoryb
Pulmonary embolism	824	39 064	518 344	1.59
Deep vein thrombosis	1559	39 779	524.353	2.97
VTE type
Idiopathic	463	38 703	514 897	0.90
Secondary (all)	1674	39 914	525 562	3.19
Cancer-related	444	38 684	514 682	0.86
Non–cancer-related	1230	39 470	521 979	2.37

^aStratified according to ages when events and person-years accrued (not baseline age).

^bPulmonary embolism and deep vein thrombosis were concurrent in 246 women.