J Thromb Haemost: Levels of coagulation factor in older adults are associated with a risk of venous thrombosis.

The occurrence of venous thrombosis (VT) increases significantly with age.
coagulation factors were also positively related to age.
recently, a study published in Journal of Thrombosis and Haemostasis, an authoritative journal of thrombosis and clotting diseases, looked at whether higher levels of clotting factors II (coagulation enzymes), VIII, IX and XI were associated with the risk of first-time VT in older adults.
401 patients aged 70 and over and 431 control subjects were included in the AT-AGE study of age and thrombosis, accessibility and genetic risk factors (AT-AGE).
year after the event, blood was collected from the patient and all control subjects to measure clotting factors.
In order to assess the risk of VT, after layering the clotting factors in the quarter and 90 percentiles, the ratio ratio was calculated and potential conflating factors (age, gender, body mass index, and research center) were corrected.
the average age of the subjects was 78 years (range: 70-100 years).
the highest quarter in the four-point scale compared to the lowest quarterile, the OR of VT is 4.5 for the VIII factor (95%CI:2.7-7.3), the IX factor is 2.4 (95% CI:1.1-5.2), and the XI factor is 1.7 (95% CI:1.0-2.9).
high coagulation enzyme was independent of the increased VT risk.
dose response relationship between the number of high coagulation factors and the risk of VT.
attribution risk (PAR) for VIII, IX and XI factor VT was 37.6%, 23.3% and 12.4%, respectively.
in this study of older adults, higher coagulation factors VIII, IX and XI were positively associated with VT risk, while the clotting enzyme principle was not.
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