Thromb Haemost 2003; 90(05): 835-838
DOI: 10.1160/TH03-05-0311
Blood Coagulation, Fibrinolysis and Cellular Haemostasis
Schattauer GmbH

Risk factors for venous thrombosis in the black population

Raj K. Patel
1  Department of Haematological Medicine, King’s College Hospital, London, United Kingdom
,
Elizabeth Ford
1  Department of Haematological Medicine, King’s College Hospital, London, United Kingdom
,
Jill Thumpston
1  Department of Haematological Medicine, King’s College Hospital, London, United Kingdom
,
Roopen Arya
1  Department of Haematological Medicine, King’s College Hospital, London, United Kingdom
› Author Affiliations
Further Information

Publication History

Received 22 May 2003

Accepted after revision 24 June 2003

Publication Date:
05 December 2017 (online)

Summary

Risk factors for venous thrombo-embolism (VTE) in the black population are poorly characterized. Of 142 black cases tested a genetic cause was identified in only 9.1%: 4.2% had protein C deficiency, 2.8% protein S deficiency, 0.7% antithrombin deficiency and 1.4% were heterozygous for FV Leiden. We hypothesised that elevated factor VIII levels constitute a candidate risk factor for venous thrombosis in the black population. Factor VIII (FVIII:C) levels were determined in 100 black patients with VTE and 100 black controls in a case-control study. Of the patients 34% had a FVIII:C above 228 IU/dL (the 90thcentile value in normal blacks) compared to 10% controls. Relative to those with FVIII:C below this value, odds ratio (OR) for risk of VTE was 4.64 (95% CI 2.02-10.85). When FVIII:C below 150 IU/dL was used as a comparator, OR was 11.1 (95% CI 4.29-29.43). There was evidence for a dose-response relationship. We propose that raised FVIII:C is a major risk factor for VTE in black subjects with prevalence and odds ratio exceeding those reported for white subjects.