. 2020 Nov 10;4(21):5595–5606. doi: 10.1182/bloodadvances.2020002268

Table 2.

VTE recurrence risks in selected studies evaluating risk factors for recurrence

Study	Type of study/nature of initial VTE^*	Cumulative recurrence risk for entire group	Predictors of VTE recurrence	VTE recurrence risk RR or HR (95% CI)
Heit et al 2000 ⁽⁴⁵⁾	Prospective cohort study: provoked and unprovoked first VTE	1 y: 12.9%	Male sex	Male vs. Female: HR 1.29 (1.06-1.57)
Heit et al 2000 ⁽⁴⁵⁾	Prospective cohort study: provoked and unprovoked first VTE	10 y: 30.4%	Male sex	Definite/probable VTE: 2.07 (1.60-2.67)
Kyrle et al 2004 ⁽⁴⁶⁾	Prospective cohort study: first unprovoked VTE	5 y:	Male sex	Male vs. Female: RR 3.6 (2.3-5.5)
		Men: 30.7% (23.8-37.6)
		Women: 8.5% (5.0-12.0)
Baglin et al 2004 ⁽⁴⁷⁾	Prospective single-center cohort study: provoked/unprovoked VTE	2 y:	Male sex	Male vs. Female: HR 2.66 (1.49-4.77)
		Men: 19.2%
		Women: 7.7%
Rodger et al 2008 ⁽⁴²⁾	Multicenter prospective cohort study: First unprovoked VTE	N/R	Male sex	Annual recurrence risk:
				Men 13.7% (10.8-17.0%)
				Women: 5.5% (3.7-7.8%); P < .001
Lijfering et al 2009 ⁽⁴⁸⁾	Post hoc analysis of pooled data from family cohort studies: Provoked and unprovoked VTE	N/R	Male sex	Male vs. Female: RR 1.6 (95% CI, 1.3-2.0)
Christiansen et al 2010 ⁽³³⁾	Prospective follow-up of case-control study; provoked and unprovoked first VTE	N/R	Male sex	Men: IR 41.2/1000 patient-years
				Women: IR 14.2/1000 patient -years
				HR 2.8 (1.4-5.7) (unprovoked VTE)
Douketis et al 2011 ⁽⁴⁹⁾	Patient-level meta-analysis (provoked and unprovoked VTE)	1 y:	Male sex	Male vs. Female: HR 2.2 (1.7-2.8)
		Men: 9.5% (7.9%-11.4%)
		Women: 5.3% (4.1%-6.7%)
		3 y:
		Men: 19.7% (16.5%-23.4%)
		Women: 9.1% (7.3% −11.3%)
Khan et al 2019 ⁽⁸⁾	Meta-analysis first unprovoked VTE	2 y: 16% (13-19%)	Male sex	First year:
		5 y: 25% (21- 29%)		Men: 11.9/100 patient-years (9.6-14.4) Women: 8.9/100 patient-years (6.8-11.3)
		10 y: 36% (28-45%)		Rate ratio 1.4 (1.3-1.6)
Palareti et al 2006 ⁽⁵⁰⁾	RCT first unprovoked VTE	N/R	D-dimer 1 mo after D/C AC	HR (abnormal vs normal D-dimer without AC) 2.49 (1.35–4.59)
Verhovsek et al 2008 ⁽⁵¹⁾	Meta-analysis (first unprovoked VTE)	N/R	Abnormal D-dimer levels after anticoagulation completion	Positive D-dimer results:
				−8.9%/year (5.8%-11.9%)
				Negative D-dimer results:
				−3.5%/year (2.7%-4.3%)
Cosmi et al 2010 ⁽⁵²⁾	Prospective multicenter study (first unprovoked VTE)	N/R	D-dimer 1 mo after D/C AC	Persistently abnormal D-dimer: 27%/person-years (12-48)
				Persistently normal D-dimer: 2.9%/person-years (1-7)
				Adjusted HR 7.9 (2.1-30)
Palaretti et al 2014 ⁽⁵³⁾	Prospective clinical management study (VTE associated with no/weak risk factors)	N/R	D-dimers after AC	1. Persistently negative D-dimer after D/C AC:
				3.0 per 100 person-years (2.0-4.4)
				2. Positive D-dimers, refused to resume AC:
				8.8 per 100 person-years (5-14.1)
				HR 1 vs 2: 2.92 (1.87-9.72)

Kearon et al 2015 ⁽²⁹⁾	Prospective clinical management study (first unprovoked VTE)	N/R	D-dimers at end of AC: if second test negative >1 mo, AC not restarted in men/women	Persistently negative D-dimers:
				Overall: 6.7% (4.8-9.0%)/person-year
				Men: 9.7% (6.7-13.7%)/person-year
				Nonestrogen women: 5.4%
				(2.5-10.2%)/person-year
				Estrogen women: 0.0% (0.0-3.0%)/person-year
Tan et al 2011 ⁽⁵⁴⁾	Systematic review: studies including provoked and unprovoked first VTE	N/R	Residual vein thrombosis	Residual vein thrombosis vs. none: Overall: OR 2.02 (1.62-2.5), unprovoked VTE: OR 1.5 (1.12-2.01)
Carrier et al 2011 ⁽⁵⁵⁾	Systematic review (unprovoked and provoked first VTE)	N/R	Residual vein occlusion	Residual vein occlusion vs. none: Any VTE: OR 1.5 (1.1-2.0) unprovoked VTE: OR 1.24 (0.9-1.7)

AC, anticoagulation; D/C, discontinued; HR, hazard ratio; N/R, not reported; OR: odds ratio; RR, relative risk.

In these studies, VTE events included DVT and PE.