A study presented at the Digestive Diseases Week (3–6 May 2014, Chicago, USA) has shown that iron isomaltoside 1000 may have a clinical benefit in reducing secondary thrombocytosis in patients with inflammatory bowel disease.
Secondary thrombocytosis, defined as an increased platelet count is often present in patients with iron deficiency anaemia and inflammatory bowel disease. Iron therapy has been found to normalise elevated platelets in these patients. This study investigated the effect of high-dose intravenous iron isomaltoside 1000 on hematopoietic parameters, including haemoglobin levels, transferrin saturation, and ferritin and platelet counts.
This study (a subanalysis of the PROCEED trial) randomised 225 patients to either two once weekly infusions of up to 1000 mg iron over 15 minutes or four once weekly 500 mg infusions over 2 minutes. The total iron requirement was calculated according to an adapted version of the Ganzoni formula, where the target haemoglobin was 13 g/dL.*
Platelet count decreased from a mean of 370 x 109/L at baseline to 297 x 109/L at Week 8 (p<0.0001); the decrease was dose-dependent. Patients treated with >1000 mg iron had a significantly higher decrease in platelet count compared to those treated with <1000 mg (p=0.001). Further analyses revealed that an increase in haemoglobin of 1 g/dL was associated with a decrease of 10.7 x 109/L in platelet count. In addition, an increase in transferrin saturation was also associated with a decrease in platelet count (p=0.0025). No major safety issues were reported.
The researchers concluded that iron isomaltoside 1000 may reduce secondary thrombocytosis in patients with iron deficiency anaemia and inflammatory bowel disease. Further studies are required to establish whether this would lead to a potential reduced risk of thrombosis in this patient group.
Further information is available in the May supplement of Gastroenterology. For more articles on the treatment of iron deficiency in gastroenterology, please click here.
* Total iron deficit = body weight [kg] x (Target haemoglobin – Actual haemoglobin) [g/dL] x 2.4 + 500 mg (to replenish the iron store if body weight >35k g)