Risk Factors for Venous Thrombotic Disease

Abstract

IntroductionVenous thrombosis occurs in about 1 per 1,000 individuals per year.1,2 It usually affects the deep veins of the leg, but may occur in other sites, such as the upper extremities, cerebral sinus, liver and portal veins, or retinal veins. It also may occur in the superficial veins, usually in the leg. The predilection of thrombosis occurring in the leg is the result of the upright position of man, with the resulting slow antigravitational flow of blood in the veins of the leg. Embolization occurs when parts of the clot dislodge and are transported by the blood flow, usually through the heart to the vasculature of the lungs.3 Thrombosis is a serious disorder. It may be fatal by pulmonary embolism, although this is rare (case fatality rate of venous thrombosis is estimated at 1% to 2%). A common, and often disabling, consequence of deep vein thrombosis is postthrombotic syndrome, with symptoms ranging from discoloration to pain and ulceration.4 Because thrombosis is not very rare and often has serious consequences, prophylactic treatment is focussed on preventing first events and recurrences through adequate knowledge about risks and risk factors.5

Venous thromboembolism prophylaxis in medically ill patients and the development of strategies to improve prophylaxis rates

“…Current literature highlights numerous risk factors for VTE in the medically ill patient. These clinical risk factors include increasing age, acute respiratory failure (asthma, COPD), congestive heart failure (class III or IV), prolonged immobility, stroke or paralysis, previous VTE, cancer and its treatment, major surgery (operations involving the abdomen, pelvis, and lower extremities), ICU admission, known thrombophilia, obesity, acute infection, central venous catheters, estrogen, smoking, acute inflammatory bowel disease, rheumatologic disease, long travel, family history of VTE, nephrotic syndrome, and varicose veins [3,[7][8][9][10].…”

Progressive chromogenic anti-factor Xa assay and its use in the classification of antithrombin deficiencies

“…The relative risk of VTE in patients with AT deficiency was estimated to be approximately 25-50-fold [29][30][31][32]. AT deficiency also represents an increased risk of pulmonary embolism and recurrence of VTE [16,33,34].…”

“…Anti-FXa determinations were also performed on the plasma samples from 24 first-degree relatives of the patients, in which causative AT mutation was excluded by DNA sequencing. The reference sample group consisted of 188 apparently healthy individuals, 104 females and 84 males, median age: 34 [interquartile range (IQR): [26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41]. Exclusion criteria for the healthy group were the history of arterial and venous thrombosis and, in the case of women, being on oral contraceptive or pregnancy.…”

Epidemiology of venous thromboembolism

“…Hypertriglyceridemia doubles the risk of VTE in postmenopausal women [162]. However, the risk associated with atherosclerosis, or other risk factors for atherosclerosis, remains uncertain [118, [163][164][165][166][167] 172,176], and therapy with the selective estrogen receptor modulator, raloxifene [177]. First and third generation oral contraceptives convey higher risk than second generation oral contraceptives [173].…”