Inherited risk factors in low-risk venous thromboembolism in patients under 45 years

Venous thromboembolism (VTE) is a complex disease and an important preventable cause of morbidity and mortality today. Many genetic and acquired factors contribute to its aetiology. The aim of the present study is to investigate the incidence of inherited risk factors for thrombophilia in patients under 45 years of age who presented with VTE without having a major acquired risk factor.

Of 96 VTE patients who presented to our outpatient department between February 2012 and November 2013, 58 were considered eligible for the study. Blood samples taken for thrombophilia testing were investigated in a molecular genetics and diagnosis laboratory. These data were collected prospectively and analysed retrospectively.

The mean age of patients in our study was 39.12 ± 2.1 years. Of the 58 patients, 30 had factor V Leiden mutation (5 homozygous, 25 heterozygous), 16 had prothrombin gene mutation, 24 had methylenetetrahydrofolate reductase C677T mutation (5 homozygous, 19 heterozygous), 18 had protein C deficiency, 17 had protein S deficiency, 14 had antithrombin III deficiency and 13 had hyperhomocysteinaemia. We observed that at least one inherited risk factor was present in most of the patients with VTE (n = 45), a finding that was compatible with those of previous studies.

Inherited risk factors are common among patients who present with VTE but have no major acquired risk factors. We conclude that these patients should be further evaluated for evidence of molecular risk factors.