Abstract: Objective To evaluate the cognitive function of chronic obstructive pulmonary disease (COPD) stable patients with ExtendedScale for Dementia (ESD). Methods 37 patients with stable COPD (COPD group) and 40 healthy persons (control group) were enrolled.The COPD patients were divided into different groups as their PaO2. They were assessed with ESD and Mini Mental Status Examination(MMSE). Results The total score of ESD and the subtest scores of ESD in leaning, memory, calculation, constructive function were significantlylower in the COPD group than in the control group (P<0.001). The total score of MMSE and the subtest scores of MMSE in memory,attention and calculation, short- and long-term memory were significantly lower in the COPD group than in the control group (P<0.05). Thetotal score and the subtest scores in learning, memory, calculation of ESD were lower in patients with PaO2<60 mmHg than those withPaO2≥60 mmHg (P<0.05), same as the total score and the subtest scores in memory, attention and calculation, short- and long-term memoryof MMSE (P<0.05). Both ESD and MMSE correlated significantly with PaO2 (P<0.01). Conclusion ESD can be used as an evaluationtool for cognitive function in stable patients with chronic obstructive pulmonary disease.

Key words: chronic obstructive pulmonary disease, cognitive function, Extended Scale for Dementia, Mini Mental Status Examination