| Objective:Cognitive impairment(CI)has a serious impact on human health,but there are few correlational studies on Tibetan CI in Tibet.By investigating the prevalence of CI in the Tibetan middle-aged and elderly population in Tibet epidemiology and exploring its related influencing factors,it is conducive to strengthening the understanding of CI,improving the research on CI in plateau areas,and providing a reference for the early identification and screening of local CI high-risk groups.Methods:1.Reliability and validity analysis of the Tibetan version of the MMSE scale: In August 2021,2 townships ≥ 45-year-old Tibetan population in Naqu City were random selected to conduct a pre-survey in the form of questionnaires.The revised Tibetan version of MMSE was used to assess cognitive function using a unified questionnaire and standardized survey language,IBM SPSS Statistics 25.0 software was used for data analysis.The reliability test was performed the rater test,and the internal consistency reliability was tested by Cronbach ’s α coefficient.The content validity index of the scale was tested by Spearman-Brown correlation test between item score and total score,and the contribution factors of different cognitive items of Tibetan MMSE were analyzed by multiple stepwise regression method.2.Study on the Releted influencing factors of cognitive impairmengt in Tibetan middle-aged and elderly people in Tibet: Using the current situation study,From August 2021 to August 2022,Tibetan residents aged45 and above living in Gaize County(Dongcuo Township)of Ali prefecture,Bange County(Jiaqiong Township)of Naqu city,Nima County,Shuangshu County,Anduo County(cuoma Township,Tandui Township),Naidong District(Kesong Village)of Shannan City,and Liemei Township of Longzi County were investigated by Multi-stage cluster random sampling method survey.After removing the missing data,749 people,including 316 men and 433 women,all respondents used the Tibetan MMSE scale to assess cognitive function,and performed questionnaire filling,physical examination,genetic sample collection,and laboratoryrelated examination.Chi-square test,nonparametric rank sum test,univariate and multivariate binary logistic regression were used for correlation Statistical analysis.Results :1.The Cronbach ’s of the Tibetan version of MMSE was 0.83,suggesting that the scale had good internal consistency.Thirty people were randomly selected and retested using the Tibetan version of the MMSE questionnaire.The correlation coefficient of the two retest scores was r =0.79(P < 0.05).The multiple stepwise regression method was used to evaluate the validity of each contribution factor of the Tibetan version of MMSE for dementia screening,and the results were statistically significant(P < 0.05).2.There were 749 subjects in this study,with a male to female ratio of 0.73 : 1 and an average age of 57.3 ± 8.97 years.There were 207 people(27.6 %)who met the CI criteria,with an average age of 59.2 ± 9.69 years.The detection rate of CI in women(36.3 %)was higher than that in men(15.8 %)(P < 0.001);The detection rate of CI increased with age(P < 0.001);Compared with high altitude,CI detection was higher at ultrahigh altitude(P < 0.001).3.The detection rate of CI at the same altitude was significantly different between male and female groups(P < 0.05),and the detection rate of CI at different altitudes and the same gender was significantly different in males(P < 0.05);There were significant differences among different age groups in high altitude areas(P < 0.05).Compared with the detection rate of CI in the same age group in ultra-high altitude areas,the difference of CI in 55-age group in high altitude areas was statistically significant(P < 0.05),while there was no significant difference in other age groups;There were significant differences in different educational levels in high altitude areas(P < 0.05).Compared with the same educational level at ultra-high altitude,the detection rate of CI in high altitude areas was statistically significant in the illiterate group(P < 0.05).4.The results of the comparison of age and blood biochemical indexes of different cognitive groups showed that the differences between age,BMI,waist circumference,RBC,HGB,DBP,CR,UA,LDL-C,and Hcy were significant(P<0.05);The biochemical results of CI population with different genders were statistically significant in abnormal serum creatinine,hyperuricemia and Hcy classification(P < 0.05).5.The results of Apo E gene polymorphism showed that there was no significant difference in Apo E genotype distribution and Apo E allele frequency between cognitive impairment group and cognitive normal group.The risk analysis results of Apo E ε4 gene and CI showed that Apo Eε4 gene was significantly correlated with the occurrence of cognitive impairment(P<0.001)OR=2.4(95%CI 1.461～4.046).6.The results of MTHFR and MTRR gene polymorphisms showed that the genotype and allele frequency distribution of MTHFR and MTRR gene polymorphisms in different cognitive groups was not statistically significant.7.With the same altitude,there were statistically significant differences in the factors and total scores of the Tibetan version of the MMSE scale between the cognitive normal group and the cognitive impairment group(P < 0.001);Compared with the high altitude cognitive normal group,the distribution of orientation,immediate memory,computing power,short-term memory,language ability and MMSE total score in the ultra-high altitude cognitive impairment group was statistically significant(P < 0.001);Compared with the high altitude cognitive impairment group,the ultra-high altitude cognitive normal group had significant differences in orientation,immediate memory,computing power,short-term memory,language ability and MMSE total score distribution(P < 0.001).8.Multivariate Logistic regression analysis showed that gender,age,total income of the whole family in the past year,altitude,frequency of physical exercise and hyperlipidemia were the main influencing factors(P< 0.05);Compared with men,Women are at higher risk of CI than men(OR = 2.690,95 % CI 1.665-4.344,P < 0.001);The older the age,the higher the risk of CI(OR = 1.027,95 % CI 1.003-1.050,P < 0.05);Compared with the total income of the whole family in the past year <20000,the risk of CI in 20000～5999 and >60000 was lower and statistically significant(OR = 0.455,95 % CI 0.279-0.739,P < 0.05;OR= 0.448,95 % CI 0.204-0.982,P < 0.05);Compared with high altitudes,the risk of CI at very high altitudes was higher than at high altitudes,and the difference was statistically significant(OR = 1.635,95 % CI 1.424-1.950,P < 0.05);Compared with never participating in exercise,The risk of developing CI was higher when exercising daily or almost daily than when exercising at all(OR = 0.299,95 % CI : 0.150-0.596,P < 0.05);Compared with those with normal lipids,the risk of CI with dyslipidemia was higher than that in those with normal lipids,and the difference was statistically significant(OR = 1.668,95 % CI : 1.451-1.990,P < 0.05).Conclusions:1.The application of the Tibetan version of MMSE scale in Tibetan population has good feasibility reliability and validity,and can be used in the detection of cognitive function in Tibetan population.2.Studies on Apo E gene polymorphism showed that the frequency of4 alleles in cognitive impairment group was higher than that in normal cognitive group,and Apo E ε4 alleles were significantly correlated with the occurrence of CI.3.CI at different altitudes showed significant changes in the factors and total scores of MMSE scale,such as orientation,immediate memory,and computing power.4.In this cross-sectional study in Tibet,the overall prevalence of CI in participants aged 45 and above was 27.6 %.Gender,age,altitude,frequency of physical exercise,hyperlipidemia and total annual income were the influencing factors of CI.Among them,women,old age,elevation,lack of physical exercise,hyperlipidemia,and low annual total income are risk factors for CI. |
