Table 1.

Association-inherited thrombophilia with risk of VTE in children.

	Prevalence (%) (population)	Summary OR (95% CI) first VTE (19)	Summary OR (95% CI) recurrent VTE (19)	Annual risk (%, 95% CI) for recurrence after non-CVC-related VTE (31)	Annual risk (%, 95% CI) for VTE in asymptomatic carriersa (32)
Antithrombin deficiency	0.02	8.73 (3.12–24.42)	3.37 (1.57–7.20)	5.4 (2.6–10)		2.82 (1.63–4.80)
Protein C deficiency	0.2	7.75 (4.48–13.38)	2.53 (1.30–4.92)	1.3 (0.3–3.8)
Protein S deficiency	0.03–0.13	5.77 (3.07–10.85)	3.76 (1.57–8.04)	0.7 (0.08–2.4)
Factor V Leiden	3–7	3.56 (2.57–4.93)	0.77 (0.40–1.45)		0.25 (0.12–0.53)
Prothrombin mutation	1–2	2.63 (1.61–4.29)	2.15 (1.12–4.10)		0.42 (0.17–1.01)

^aFirst- or second-degree relative of pediatric patient with venous thromboembolism (VTE) and thrombophilia.

OR, odds ratio; CI, confidence interval; CVC, central venous catheter.