TABLE 3.

Cumulative Venous Thromboembolism (VTE) Recurrence Among Women Experiencing an Incident VTE Event, by VTE Type: Iowa Women's Health Study, 1986–2004

Recurrenceb	No. of Recurrent VTE Events	No. of VTE Eventsa	Cumulative IR, %
VTE type
All VTE types, y
1	58	1691	3.4
2	119	1691	7.0
Idiopathic, y
1	16	430	3.7
2	30	430	7.0
Secondary, y
1	42	1261	3.3
2	89	1261	7.1
Secondary VTE type (all)
Cancer-related, y
1	14	244	5.7
2	30	244	12.3
Non–cancer related, y
1	28	1017	2.8
2	59	1017	5.8

Note. IR = incidence rate.

^aGiven the 6-month lag period required to define recurrence, only VTE patients not censored within the first 6 months after their incident event were eligible to have experienced a recurrent event (446 patients were censored, 366 who died and 80 who were no longer enrolled).

^bA 6-month lag period was required between the discharge date of the incident event and the admission date of the subsequent event to distinguish index events from recurrent events.