we further attempted to find morphological evidence
that accounts for cognitive impairment in COPD patients.
Therefore, we measured hippocampal volume in patients
with different severity of COPD. Surprisingly, we found
that hippocampal atrophy did occur in COPD patients
and there were significant correlations with PaO2, SaO2
and MMSE which may account for cognitive decline in
COPD patients. However, the mechanism is poorly understood.
One possible explanation is that COPD patients exist
in a state of low-grade systemic inflammation [3] and persistent
airflow limitation which leads to chronic hypoxemia.