Association between serum ferritin level and perihematoma edema volume in patients with spontaneous intracerebral hemorrhage

Background and Purpose - Preclinical evidence indicates that iron plays a key role in mediating neuronal injury and edema formation after intracerebral hemorrhage (ICH). However, the clinical role of iron in patients with ICH has not been well studied. We undertook this exploratory study to investigate the association of serum ferritin, as an indicator of body iron load, with perihematoma edema after ICH. Methods - We retrospectively reviewed prospectively-collected clinical and laboratory data from 23 consecutive patients with acute spontaneous ICH who had a CT scan and serum ferritin checked on admission, and a follow-up CT scan 3 to 4 days afterward. We measured hematoma and edema volumes on admission and follow-up scans, and calculated the relative edema volume to correct for hematoma volume. We used Spearman correlation coefficient to determine the association of various variables with relative perihematoma edema volume. Results - Whereas the median hematoma volume increased by approximately 28% from baseline to day 3 to 4, the relative edema volume almost doubled during this time period. We observed a significant positive correlation between serum ferritin and relative perihematoma edema volume on day 3 to 4 (r = 0.78; P = 0.002), but not at baseline; and little correlation between the changes in hematoma volumes and corresponding relative edema volumes (r = 0.14). There was a trend for a positive correlation between body temperature and relative edema volumes. Conclusions - Our findings support the notion that delayed iron toxicity plays a role in causing brain injury and edema formation after ICH. These findings are preliminary and need to be further investigated in future studies.