Low iron levels linked to increased VTE risk
MedWire News: Low serum iron levels are associated with an increased risk for venous thromboembolism (VTE), a study of patients with hereditary hemorrhagic telangiectasia (HHT) shows.
This suggests that treating iron deficiency might be important for preventing VTE, say Claire Shovlin (Hammersmith Hospital, London, UK) and colleagues.
The researchers explain that patients with HHT - an inherited condition that results in chronic bleeding from nasal and gastrointestinal telangiectasia - have unexplained high rates of VTE.
"Elevated levels of coagulation factor (F)VIII at least 6 months from any acute illness, infection, or thrombosis are a strong predictor of long-term VTE risk in HHT," they add in the journal Thorax.
To better understand the association between FVIII, VTE, and HHT, Shovlin and team studied 609 patients with the condition.
Of these patients, 40 developed radiologically confirmed VTE (pulmonary embolism or deep vein thrombosis), corresponding to an incidence rate of 138 cases per 100,000 person-years.
The researchers report that there was an inverse association between serum iron and factor VIII (measured 6 months from any known thrombosis/illness) that persisted after adjustment for age, inflammation, and/or von Willebrand factor.
"Iron response elements within untranslated regions of factor VIII transcripts provide potential mechanisms for the association," write Shovlin et al in the journal Thorax.
The team found that each µmol/L increase in serum iron level was associated with a 9% decrease in the risk for VTE. This indicates that people with a serum iron level of 6 mmol/L have a 2.5-fold increased risk for VTE compared with those whose iron level is in the middle of the normal range (17 µmol/L), says the team.
Adjustment for FVIII attenuated the association between VTE and iron, indicating that the relationship may be dependent on FVIII.
"Our study shows that in people with HHT, low levels of iron in the blood is a potentially treatable risk factor for blood clots," Shovlin told reporters.
"There are small studies in the general population which would support these findings, but more studies are needed to confirm this. If the finding does apply to the general population, it would have important implications in almost every area of medicine," she concluded.
By Laura Dean