A Study On Cognition And Magnetic Resonance Spectroscopyin Patients With Chronic Obstructive Pulmonary Disease In High And Middle Altitudes

Objective:To observe the prevalence of cognitive impairment and the changes of brain metabolites in the left hippocampus and left frontal lobe of patients with AECOPD in middle and high altitude regions,and understand the effects of different altitudes on brain metabolism.Methods:According to the inclusion criteria and exclusion criteria,the patients with AECOPD aged ? 60 years who were hospitalized in middle altitude areas(Xining,2260m)and high altitude areas(Haixi,3500m)were assessed with blood gas analysis,pulmonary function measurement,chest CT,and MMSE.The patients were divided into cognitive impairment group and cognitive normal group.Among the patients,195(including 38 cognitive impairment,157 cognitive normal)and 57(including 15 cognitive impairment,42 cognitive normal)were enrolled in the study.The prevalence of cognitive impairment and the related statistical analysis were calculated.In order to avoid sampling error and systematic error,we randomly selected 38 AECOPD patients with normal cognitive function in the middle altitude area,and the patients with cognitive impairment in the area,and the patients with AECOPD at high altitude.The left hippocampus and left frontal lobe were examined by magnetic resonance proton spectroscopy,and N-acetylaspartate(NAA),choline(Cho),myoinositol(mI),and creatine(Cr)were detected.NAA/Cr,mI/Cr and Cho/ Cr were calculated and correlated analysis was performed.Results:1.There is no difference in the prevalence of cognitive impairment among AECOPD populations in middle and high altitude regions,and it has nothing to do with gender(P <0.05).2.(1)The NAA/Cr ratios in the left hippocampus and the left frontal lobe of the AECOPD cognitive impairment group in middle and high altitude regions were lower than those in the normal cognitive function group(P <0.05);The mI/Cr ratios of the left hippocampus and the left frontal lobe of the AECOPD cognitive impairment group in the middle and high altitude regions were higher than those in the normal cognitive function group(P <0.05);The Cho/ Cr ratios in the left hippocampus and the left frontal lobe of the AECOPD cognitive impairment group in the middle and high altitude regions was not significantly different between the two groups(P> 0.05).(2)The NAA/Cr and mI/Cr ratios in the left hippocampus of the AECOPD cognitive impairment group in middle and high altitude regions were higher than those in the left frontal lobe group(P <0.05);The Cho/ Cr ratios was not significantly different between the two groups(P> 0.05).(3)There was no significant difference in NAA/Cr,mI/Cr,and Cho /Cr ratios in the left hippocampus and left frontal lobe of patients with COPD combined with cognitive impairment in the middle and high altitude groups(P> 0.05).Conclusions: 1.Patients with AECOPD can have cognitive dysfunction in two areas at high and middle altitudes,and there is no significant difference.2.The changes of brain metabolism in patients with cognitive impairment in two areas of middle and high altitude are similar,and the changes of brain metabolism are independent of altitude.3.MMSE and ~1H-MRS can be used as an important tool for the diagnosis of cognitive function in patients with AECOPD.