Yu et al.¹ reported that iron levels in the temporal cortex were reduced in patients with Parkinson disease (PD) compared with age-matched controls. They also determined that patients with Alzheimer disease (AD) had no change in iron levels in the temporal cortex. We would like to know whether Yu et al.¹ included any patients with memory disturbance in this study.

Sofic et al.² reported an increase in iron levels in the substantia nigra of patients with PD, and showed a decrease in iron levels in the temporal cortex, thereby suggesting that the increase in iron levels may be associated with parkinsonian symptoms. In addition, did Yu et al. find a relationship between iron level in the temporal cortex and cognitive disability scales used in their study? Symptoms associated with the temporal lobe are not seen in patients with typical PD, so we would like to know the iron levels in other brain regions.

Iron may be associated with pathogenesis in PD and further study is needed to determine the relationship between iron and its distribution.

Author Response

Memory disturbances were present in patients with AD in this study. However, no changes were observed in patients with PD, so we did not find a relationship between iron levels in the temporal cortex and cognitive disability scales in our cohort. Iron levels in other brain regions were not determined because our access to samples was restricted.