Upper extremity deep venous thrombosis in the population-based Malmö thrombophilia study (MATS). Epidemiology, risk factors, recurrence risk, and mortality.

BACKGROUND: Deep venous thrombosis (DVT) is much less common in the upper than in the lower extremity. Furthermore, there is limited information on risk factors for and the prognosis of upper extremity (UE)DVT in the general population. AIMS: To estimate incidence, risk factors, and prognosis in UEDVT. MATERIAL AND METHODS: Among a total of 1203 patients with venous thromboembolism (VTE) diagnosed during 1998-2006 in the prospective population-based Malmö thrombophilia study, 63 (5%, 33 men [52%, age 54+/-17years], and 30 women [48%, age 55+/-22years]) had UEDVT and were evaluated concerning risk factors, treatment, recurrent VTE, and mortality. RESULTS: At diagnosis, 19(30%) patients had known malignancy and 6(10%) had VTE heredity. Among female UEDVT patients 4(13%) used hormone therapy, 1(3%) was pregnant, while none was in the postpartum period. Of all 63 UEDVT patients, 12(19%) were heterozygous, and 3(5%) homozygous for the Factor V Leiden (FVL)-mutation. Two (3%) patients were heterozygous for the prothrombin mutation, and 1 patient (1.6%) showed both heterozygous FVL-mutation and lupus anticoagulant antibodies. Phlebography had been used for diagnosis in 48(76%), ultrasonography in 16(25%), and computer tomography (CT) in 9(14%) patients. Twenty-two patients (35%) were treated in hospital, and the remaining 41(65%) as out-patients. Sixty-two (98%) was treated with low molecular weight heparin (LMH), 60(95%) with oral anticoagulants (OAC), 3(5%) with unfractionated heparin, and 3(5%) with thrombolysis. VTE recurrence rate during median 62 (range 31-117) month of follow-up was 8/63(13%). Fifteen (24%) UEDVT patients died during follow-up; 9(47%) of the 19 patients with known malignancy at diagnosis and 6(14%) of the other patients. Yearly incidence of UEDVT was 3.6/100.000 (95% confidence interval [CI], 3.3 - 4.03). CONCLUSION: Malignancies and the FVL mutation were common among patients with UEDVT. Mortality during follow-up vas high.