[Intravenous ferric carboxymaltose-associated hypophosphatemia in patients with iron deficiency anemia. A common side...

To determine the frequency, severity, time of onset and factors associated with the development of hypophosphatemia (HF) in patients with iron deficiency anemia treated with intravenous ferric carboxymatose (ivFCM).

Retrospective cohort study in patients iron deficiency anemia who received ivFCM and had an a prior and subsequent determination of serum phosphate. We carried out a comparative analysis between baseline and post-ivFCM levels of serum phosphate. In order to identify variables independently associated with HF a logistic regression analysis was also performed.

One hundred twenty-five patients were included. HF frequency was 58%. The median time to onset of HF was 18 days. Age, baseline ferritin levels and baseline phosphate levels were independently associated with the development of HF. The risk of HF in patients with baseline phosphate levels ≤ 3.1mg/dl was 67% higher than patients with ≥ 3.7 mg/dl.

ivFCM-associated HF is a frequent, early and, sometimes, prolonged effect in patients with iron deficiency anemia. Serum phosphate levels should be monitored after ivFCM administration, especially in older patients and in those with lower baseline phosphate or ferritin levels.