Risk factors and cerebral glucose metabolism of mild cognitive impairment in Parkinson＇s disease

Abstract

Objective To investigate the risk factors of Parkinson＇s disease（PD）with mild cognitive impairment and mode of cerebral glucose metabolism. Methods One hundred and one non-dementia PD patients were assessed with Montreal Cognitive Assessment（MoCA）and divided into the PD with mild cognitive impairment （PD-MCI）group and the PD non-cognitive impairment（PD-NC）group. The demographic details, clinical features,Unified Pakinson＇s Disease Rating Scale（UPDRS）, Hohen-Yahr rank and Hamilton Depression Scale（HAMD）were compared between the two groups. Patients in Hohen-Yahr stage 1 underwent positron emission tomography（PET）with 18F-fluorodeoxyglucose（18F-FDG）to show glucose metabolism. Results Seventy-seven（74. 3%）PD patients had mild cognitive impairment PD-MCI group had higher score in UPDRS 1st（mentation ,behavior and mood）,2nd （activity of daily living）and 3rd（motor examination）subscale（2.48 ± 1.51,10. 71 ± 4. 88,22.31 ± 12.70）than PD-NC group（1.65 ± 1.29,8.15 ±2. 20,15.92 ±7.56,P 〈0.05）respectively. The FDG metabolism ratio of frontal cortex,parietal cortex and occipital cortex decreased more significantly in PD-MCI than in PD-NC（P 〈 0.05）.Conclusions The risk factors of mild cognitive impairment in PD include moter dysfunction, clinical stage and depression. The metabolic dysfunction of cortex may be the mechanism of mild cognitive impairment in PD. Key words: Parkinson＇s disease; Cognitive impairment; Positron emission tomography