Comparative analysis of the clinical features of nonvalvular atrial fibrillation among Tibetan, Han, and Hui patients in Qinghai Province, China.

BACKGROUND: Global nonvalvular AF rises, impacting health severely. In Qinghai, China's diverse setting, studying AF among varied ethnic groups is crucial OBJECTIVES: The purpose of this study was to compares cardiac features in AF among Tibetan, Han, and Hui patients to develop tailored prevention and treatment strategies for this region, the goal was to enhance the understanding of AF and provide an empirical basis for developing prevention and treatment strategies specific to this region METHODS: This study included a total of 3445 Tibetan, Han, and Hui patients diagnosed with nonvalvular atrial fibrillation and treated at the Qinghai Cardiovascular and Cerebrovascular Specialist Hospital, China, between January 2019 and January 2021. We analyzed the differences in cardiac structure, comorbidities, and other influencing factors among the different ethnic groups RESULTS: We found significant differences in gender, age, smoking history, lone atrial fibrillation, left heart failure, dilated cardiomyopathy, and diabetes between Tibetan, Han, and Hui patients (P < 0.05). Tibetan, Han, and Hui patients also differed with regard to left ventricular end-diastolic volume, left ventricular ejection fraction, fractional shortening, NT-proBNP, glycated hemoglobin, red blood cell distribution width, platelet count, platelet hematocrit, platelet distribution width, homocysteine (Hcy), C-reactive protein, and superoxide dismutase (SOD) (P < 0.05) CONCLUSION: Our study revealed variations in comorbidities, cardiac structure, and blood indexes among Tibetan, Han, and Hui AF patients, highlighting distinct patterns in complications and biomarker levels across ethnic groups.

Epidemiology and Clinical Characteristics of Cerebral Alveolar Echinococcosis in the Tibetan Region of Sichuan, China.

This study aimed to examine the epidemiology and clinical characteristics of cerebral alveolar echinococcosis in the Tibetan region of Sichuan, China. A retrospective analysis of hospitalized cases of cerebral alveolar echinococcosis from six medical units in the Garze Tibetan Autonomous Prefecture, Sichuan Province, from January 2016 to June 2021 was conducted. The study focused on the characteristics, clinical presentation, and imaging features of the disease. Of 119 cerebral alveolar echinococcosis patients, 76 were male and 43 were female. Occupationally, 62 were farmers, 46 were herdsmen, nine were monks, and two were students. The mean age was 43.9 (± 13.9) years. The primary clinical manifestations were dizziness, headaches, and epilepsy. The incidence of cerebral alveolar echinococcosis was most concentrated within 4 years after the diagnosis of hepatic alveolar echinococcosis (77/119, 64.7%). There were 86 cases (72.3%) with multiple intracranial echinococcosis lesions, with an average size of 2.0 cm × 2.5 cm. The imaging features showed that the lesion was mainly concentrated in the anterior circulation blood supply area, and the lesion had multiple aggregated small vesicular structures as its unique imaging feature. Among 98 follow-up cases, 62 could live independently (63.3%); 18 deaths were recorded (18.4%), with an approximate 5-year survival rate of 81.6%. Regular examination of patients with first diagnosis of hepatic alveolar echinococcosis without a combination of echinococcosis in other parts of the body can help monitor and prevent the occurrence of cerebral alveolar echinococcosis, improve the understanding of cerebral alveolar echinococcosis in Tibetan areas of Sichuan.

Study on the genotypes of Echinococcus granulosus in yaks and sheep from Langkazi County in Tibet Autonomous Region of China based on mitochondrial cox1 and nad1.

To determine the genotypes of the epidemic strains of Echinococcus granulosus in livestock in Tibet, samples of E. granulosus cysts were collected from 11 yaks and 62 sheep. Genomic DNA was extracted from these samples, and gene fragments of mitochondrial cytochrome c oxidase subunit I (cox1) and NADH dehydrogenase subunit I (nad1) were amplified by PCR and sequenced. DNASTAR and MAGA7.0 were employed for homology analysis and phylogenetic tree construction. Echinococcus granulosus cysts were detected in 56.2% (41/73) of the samples screened. Of these, 63.4% (26/41) were identified as E. granulosus G1 genotype (common sheep strain), 24.4% (10 /41) as G3 genotype (buffalo strain), and 12.2% (5/41) were G6 genotype (camel strain). The study concludes that yaks and sheep in Langkazi county, Tibet, carry three E. granulosus genotypes (G1, G3, and G6), with the G1 genotype the predominant genotype in the region. This study clarifies the distribution of E. granulosus genotypes, providing genetic data and insight for the surveillance and prevention of echinococcosis.

[Prevalence of taeniasis and sero - prevalence of anti - cysticercus antibody among residents in Tibetan agricultural areas of Sichuan Province].

OBJECTIVE: To investigate the prevalence and epidemiological characteristics of taeniasis and cysticercosis among residents in Tibetan agricultural areas of Sichuan Province, so as to provide insights for the prevention and control of taeniasis and cysticercosis. METHODS: From 2016 to 2022, Kangding City, Daocheng County, Derong County, Ruoergai County and Muli Tibetan Autonomous County were sampled from Tibetan agricultural areas of Ganzi Tibetan Autonomous Prefecture, Aba Tibetan and Qiang Autonomous Prefecture and Liangshan Yi Autonomous Prefecture in Sichuan Province, and 1 to 6 townships were sampled from each county (district), followed by 4 to 7 villages sampled from each township. Primary school children were sampled using a cluster sampling method, and permanent residents at ages of over 16 years were randomly sampled from each village. Participants' demographics, history of tapeworm excretion during the past year and clinical symptoms and signs of cysticercosis were collected through questionnaire surveys, and participants' stool and venous blood samples were collected. Taenia eggs were detected in stool samples using the direct smear method, and deworming was performed among taeniasis patients with areca nut-squash seeds. The tapeworm species were identified using a multiplex PCR assay, and serum specific IgG antibody against cysticercus was detected using enzyme-linked immunosorbent assay (ELISA). RESULTS: A total of 5 249 respondents participated in the questionnaire survey, including 603 respondents (11.5%) with a self-reported history of proglottids secretion during the past year. A total of 3 976 residents were subjected to stool examinations, and the detection of Taenia eggs was 6.5%. Of 258 participants undergoing deworming, there were 403 cases (94.2%) with excretions of Taenia worms or proglottids. The mean prevalence of taeniasis was 10.9% (439/4 043), and there were gender-, age- and region-specific prevalence rates of taeniasis (χ2 = 36.73, 126.31 and 163.41, all P values < 0.05). Multiplex PCR assays detected 41 cases with T. solium infections (12.5%), 197 cases with T. saginata infections (59.9%) and 91 cases with T. asiatica infections (27.6%) among 329 patients undergoing deworming, and there were region-specific prevalence rates of T. solium, T. saginata and T. asiatica infections (χ2 = 45.39, P < 0.05). In addition, the sero-prevalence of anti-cysticercus IgG antibody was 7.0% (345/4 933), and there were age- and region-specific sero-prevalence rates of anti-cysticercus IgG antibody (χ2 = 13.49 and 51.76, both P values < 0.05). CONCLUSIONS: Multiple Taenia species are prevalent in Tibetan agricultural areas of Sichuan Province and the sero-prevalence of anti-cysticercus antibody is high among residents. Monitoring and control of taeniasis and cysticercosis should be strengthened.

[Effectiveness of the central government-funded echinococcosis control programme in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022].

OBJECTIVE: To evaluate the effectiveness of the central government-funded echinococcosis control programme in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, so as to provide insights into echinococcosis control. METHODS: Administrative villages were sampled using a multi-stage cluster random sampling method from Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, and all residents at ages of 12 years and older in the sampled villages were screened for echinococcosis, and schools were sampled using a cluster sampling method, and all children at ages of 12 years and older in the sampled schools were screened for echinococcosis. Domestic dogs were sampled using a systematic random sampling method, and one domestic dog stool sample was collected from each household. Stray dog stool samples were collected outside the villages, and Echinococcus coproantigens were detected using enzyme-linked immunosorbent assay in domestic and stray dogs. In addition, echinococcosis was screened in sheep and cattle in designated slaughterhouses in Tianzhu Tibetan Autonomous County. The trends in the prevalence of echinococcosis in humans and livestock and the positive rate of Echinococcus coproantigens in dogs were examined with the Cochran-Armitage trend test. In addition, individuals screened for echinococcosis were randomly sampled from 2007 to 2022 for survey on the awareness of echinococcosis control knowledge. RESULTS: A total of 290 356 person-times were screened for echinococcosis among residents at ages of 12 years and older in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, with 1 094 residents detected with cystic echinococcosis, and the detection of echinococcosis appeared a tendency towards a gradual decline over years (χ2 = 358.602, P < 0.001). A total of 32 931 person-times were screened for echinococcosis among children at ages of 12 years and older in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, with 296 children detected with echinococcosis, and the detection of echinococcosis appeared a tendency towards a gradual decline over years (χ2 = 267.673, P < 0.001). A total of 33 230 domestic dog stool samples were tested for Echinococcus coproantigens in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, with 1 777 Echinococcus coproantigens-positive samples tested, and the positive rate of Echinococcus coproantigens appeared a tendency towards a decline in domestic dogs over years (χ2 = 2 210.428, P < 0.001), while the positive rate of Echinococcus coproantigens showed a tendency towards a rise in domestic animals from 2016 to 2022 (χ2 = 37.745, P < 0.001). The positive rate of Echinococcus coproantigens remained relatively stable in stray dogs in Tianzhu Tibetan Autonomous County, Gansu Province from 2019 to 2022 (χ2 = 0.315, P = 0.575). A total of 10 973 sheep were screened for echinococcosis in Tianzhu Tibetan Autonomous County from 2007 to 2022, with 334 sheep detected with echinococcosis, and the detection of echinococcosis appeared a tendency towards a decline in sheep over years (χ2 = 53.579, P < 0.001); however, there was no significant change in the detection of echinococcosis during the period from 2015 through 2022 (χ2 = 1.520, P = 0.218). A total of 2 400 cattle were screened for echinococcosis in Tianzhu Tibetan Autonomous County from 2017 to 2022, with 231 cattle detected with echinococcosis, and the detection of echinococcosis showed a tendency towards a decline over years (χ2 = 5.579, P < 0.05). The awareness of echinococcosis control knowledge increased from 44.37% in 2007 to 94.00% in 2022 among residents at ages of 12 years and older and from 52.50% in 2007 to 92.50% in 2022 among children at ages of 12 years and older in Tianzhu Tibetan Autonomous County, respectively. CONCLUSIONS: There has been a reduction in the detection of echinococcosis in humans and domestic animals and the positive rate of Echinococcus coproantigens in dogs and a rise in the awareness of the echinococcosis control knowledge following the implementation of the central government-funded echinococcosis control programme in Tianzhu Tibetan Autonomous County, Gansu Province; however, integrated echinococcosis control measures are still required for further control of the prevalence of echinococcosis.

Weakened black carbon trans-boundary transport to the Tibetan Plateau during the COVID-19 pandemic.

The lockdowns implemented during the coronavirus disease 2019 (COVID-19) pandemic provide a unique opportunity to investigate the impact of emission sources and meteorological conditions on the trans-boundary transportation of black carbon (BC) aerosols to the Tibetan Plateau (TP). In this study, we conducted an integrative analysis, including in-situ observational data, reanalysis datasets, and numerical simulations, and found a significant reduction in the trans-boundary transport of BC to the TP during the 2020 pre-monsoon season as a result of the lockdowns and restrictive measures. Specifically, we observed a decrease of 0.0211 µgm-3 in surface BC concentration over the TP compared to the 2016 pre-monsoon period. Of this reduction, approximately 6.04 % can be attributed to the decrease in emissions during the COVID-19 pandemic, surpassing the 4.47 % decrease caused by changes in meteorological conditions. Additionally, the emission reductions have weakened the trans-boundary transport of South Asia BC to the TP by 0.0179 µgm-2s-1; indicating that the recurring spring atmospheric pollution from South Asia to the TP will be alleviated through the reduction of anthropogenic emissions. Moreover, it is important to note that BC deposition on glaciers contributes significantly to glacier melting due to its enrichment, posing a threat to the water sustainability of the TP. Therefore, urgent measures are needed to reduce emissions from adjacent regions to preserve the TP as the "Asian Water Tower."

Four-year analysis of high-risk human papillomavirus infection among women in rural areas of Nyingchi City, Tibet.

Purpose: This study aims to address the existing data gap regarding the status of high-risk human papillomavirus (HR-HPV) infection and the distribution of HR-HPV subtypes among women in rural areas of Nyingchi City, Tibet. The research objectives include providing insights for HPV vaccine development. Methods: The research collected data from two rounds of cancer screening conducted among rural women in Nyingchi City, Tibet, from 2019 to 2022. HR-HPV subtype gene detection was performed using the PCR fluorescence method on the collected samples. And then analyzed the HR-HPV infection rate among rural women in Nyingchi City, Tibet, as well as the infection rate of different HR-HPV subtypes and their distribution across different age groups. A comparison was made between the infection rates of women in rural areas outside the Qinghai-Tibet Plateau and those in Nyingchi City. Results: A total of 15,687 cases included. The overall HR-HPV infection rate among women in rural areas of Nyingchi City, Tibet, was 13.00% (2040/15,687), which was significantly higher than the rate among women in rural areas outside the Qinghai-Tibet Plateau (7.82% (9,249/118,237); χ2 = 635.7, p < 0.001). The highest HPV infection rate was observed in the 35-39 age group, with a rate of 15.31% (499/3260), which was significantly higher than the rate of 7.22% (1827/25,322) among women in the same age group in rural areas outside the Qinghai-Tibet Plateau (χ2 = 253.00, p < 0.001). The lowest HPV infection rate was found in the 50-54 age group, with a rate of 9.69% (246/2540), which was statistically different from the rate of 8.14% (1,604/19,698) among women in the same age group outside the Qinghai-Tibet Plateau (χ2 = 17.68, p < 0.001). The top three HR-HPV subtypes among women in rural areas of Nyingchi City, Tibet, were HPV52 (20.15%, 411/2040), HPV16 (12.45%, 254/2040), and HPV58 (11.96%, 244/2040). These findings align with the top three HR-HPV subtypes among women in rural areas outside the Qinghai-Tibet Plateau. Furthermore, the top three HR-HPV subtypes among women aged 35-39, 40-44, and 45-49 in rural areas of Nyingchi City, Tibet, were HPV52, HPV16, and HPV58. In conclusion, the HR-HPV infection rate among women in rural areas of Nyingchi City, Tibet, is significantly higher compared to women in rural areas outside the Qinghai-Tibet Plateau, with consistent patterns observed in the distribution of the top three HR-HPV subtypes between the two regions.

Prevalence and risk factors for dementia in the Tibetan region: A population-based cross-sectional study.

BACKGROUND: As China's population ages, the nationwide prevalence of dementia is increasing. However, the epidemiology of dementia among the Tibetan population remains unclear. OBJECTIVE: A cross-sectional study was conducted involving 9116 participants aged >50 years in the Tibetan population to investigate the risk factors and prevalence of dementia among this population. Permanent residents of the region were invited to participate, and the response rate was 90.7 %. METHODS: The participants underwent neuropsychological testing and clinical assessments, from which physical measurements (e.g., body mass index, blood pressure), demographic information (e.g., gender, age), and lifestyle details (e.g., family living arrangement, smoking, alcohol arrangement) were recorded. Dementia diagnoses were made using the standard consensus diagnostic criteria. The risk factors of dementia were identified using stepwise multiple logistic regression. RESULTS: The average age of the participants was 63.71 (standard deviation = 9.36), and there were 44.86 % males. The prevalence of dementia was 4.66 %. The multivariate logistic regression analysis revealed that older age, unmarried status, lower education level, obesity, hypertension, diabetes, coronary heart disease, cerebral vascular disease, and HAPC were independently and positively associated with dementia (P < 0.05). However, no association was found between the frequency of religious activities and the prevalence of dementia in this population (P > 0.05). CONCLUSIONS: There exist a number of contributory risk factors for dementia in the Tibetan population, with variations associated with high altitude, religious activities (i.e., scripture turning, chanting, spinning Buddhist beads, and bowing), and dietary habits. These findings suggest that social activities, such as religious activities, are protective factors for dementia.

The transcriptomic and epigenetic alterations in type 2 diabetes mellitus patients of Chinese Tibetan and Han populations.

Background: Due to the distinctive living environment, lifestyle, and diet, the Tibetan community in China has the lowest prevalence of T2DM and prediabetes among numerous ethnic groups, while Han community shows the highest statistic. In this study, we aim to conclude the clinical manifestations of both Tibetan and Han T2DM patients and their association with transcriptomic and epigenetic alterations. Methods: A cross-sectional study including 120 T2DM patients from Han and Tibetan ethnic groups were conducted between 2019 to 2021 at the Hospital of Chengdu University of Traditional Chinese Medicine. The various clinical features and laboratory tests were recorded and analyzed between the two groups. The genome-wide methylation pattern and RNA expression were determined by Reduced Representation Bisulfite Sequencing (RBBS) and Poly (A) RNA sequencing (RNA-seq) from leucocytes of peripheral blood samples in 6 Han and 6 Tibetan patients. GO analysis and KEGG analysis were conducted in differentially expressed genes and those with differentially methylated regions. Results: Compared to Han, Tibetan T2DM individuals intake more coarse grains, meat and yak butter, but less refined grains, vegetables and fruit. They also showed increased BMI, Hb, HbA1c, LDL, ALT, GGT and eGFR, and decreased level of BUN. Among the 12 patients in the exploratory cohort, we identified 5178 hypomethylated and 4787 hypermethylated regions involving 1613 genes in the Tibetan group. RNA-seq showed a total of 947 differentially expressed genes (DEGs) between the two groups, with 523 up-regulated and 424 down-regulated in Tibetan patients. By integrating DNA methylation and RNA expression data, we identified 112 DEGs with differentially methylated regions (overlapping genes) and 14 DEGs with promoter-related DMRs. The functional enrichment analysis demonstrated that the overlapping genes were primarily involved in metabolic pathways, PI3K-Akt signaling pathway, MAPK signaling pathway, pathways in cancer and Rap1 signaling pathway. Conclusion: Our study demonstrates the clinical characteristics of T2DM differ subtly between various ethnic groups that may be related to epigenetic modifications, thus providing evidence and ideas for additional research on the genetic pattern of T2DM.

Molecular characteristics and pathogenicity of a Tibet-origin mutant avian leukosis virus subgroup J isolated from Tibetan chickens in China.

Tibetan chicken is found in China Tibet (average altitude; ˃4500 m). However, little is known about avian leukosis virus subgroup J (ALV-J) found in Tibetan chickens. ALV-J is a typical alpharetrovirus that causes immunosuppression and myelocytomatosis and thus seriously affects the development of the poultry industry. In this study, Tibet-origin mutant ALV-J was isolated from Tibetan chickens and named RKZ-1-RKZ-5. A Myelocytomatosis outbreak occurred in a commercial Tibetan chicken farm in Shigatse of Rikaze, Tibet, China, in March 2022. About 20% of Tibetan chickens in the farm showed severe immunosuppression, and mortality increased to 5.6%. Histopathological examination showed typical myelocytomas in various tissues. Virus isolation and phylogenetic analysis demonstrated that ALV-J caused the disease. Gene-wide phylogenetic analysis showed the RKZ isolates were the original strains of the previously reported Tibetan isolates (TBC-J4 and TBC-J6) (identity; 94.5% to 94.9%). Furthermore, significant nucleotide mutations and deletions occurred in the hr1 and hr2 hypervariable regions of gp85 gene, 3'UTR, Y Box, and TATA Box of 3'LTR. Pathogenicity experiments demonstrated that the viral load, viremia, and viral shedding level were significantly higher in RKZ-1-infected chickens than in NX0101-infected chickens. Notably, RKZ-1 caused more severe cardiopulmonary damage in SPF chickens. These findings prove the origin of Tibet ALV-J and provide insights into the molecular characteristics and pathogenic ability of ALV-J in the plateau area. Therefore, this study may provide a basis for ALV-J prevention and eradication in Tibet.

The polymorphic analysis of cox1 and cob genes of Echinococcus granulosus in the Ngari region of Tibet in China.

Cystic echinococcosis (CE) is an important zoonotic parasitic disease caused by Echinococcus granulosus (E. granulosus). CE seriously threatens human health and the development of animal husbandry. The Ngari region is one of the world's highest endemic regions for CE, while genetic polymorphisms of E. granulosus were unclear. Paraffin slices of liver Cyst were collected from seventy-nine surgical patients with echinococcosis in the Ngari region. DNA was extracted from samples. The cox1 and cob genes of mitochondrial DNA of E. granulosus were simultaneously amplified and sequenced. The sequencing results were compared with the standard sequence (KU925397.1and HF947574.1). Phylogenetic trees and the haplotype network of cob and cox1 genes were constructed and analyzed genotypes of E. granulosus isolated from humans in the Ngari Region of Tibet. Out of 79 hydatid cyst samples collected from surgery patients, 60 isolates were identified as G1/ G3, and two isolates were identified as G6/ G7. Analysis of the cob/ cox1 genes revealed 9/7 mutations resulting in 8/6 haplotypes, respectively. The cob and cox1 neutrality indices computed by Tajima's D and Fu's Fs tests showed high negative values in Echinococcus granulosus sensu stricto (E. granulosus s. s.). The result suggested that E. granulosus in the Ngari region experienced population expansion or a negative selection. We found that G1/ G3 was still the main genotype, and G6/ G7 was found occasionally in humans of the Ngari region. Therefore, we recommend future surveys and control efforts to investigate G1/ G3 and G6/ G7 transmission in the Ngari region.

Prediction of the potential suitable habitat of Echinococcus granulosus, the pathogen of echinococcosis, in the Tibetan Plateau under future climate scenarios.

Echinococcosis is a zoonotic parasitic infectious disease caused by human or domestic animals infected with Echinococcus granulosus. China is the country with the heaviest disease burden caused by Echinococcosis in the world. Therefore, it is feasible to evaluate the prevalence and distribution of echinococcosis using relevant ecological methods, combined with environmental factors and human activities. In this study, MaxEnt was used to predict the distribution range of E. granulosus in China under current and future climate scenarios and explain the impact of environmental variables on its distribution. The results showed that elevation (El), annual mean temperature (bio1), human footprint (Hf), annual precipitation (bio12), mean temperature of warmest quarter (bio10), and mean temperature of wettest quarter (bio8) were identified as the dominant environmental variables. In Tibet, the most suitable habitats (25.9 × 104 km2) of E. granulosus were distributed in Nyingchi and Qamdo in the east, Shigatse and Shannan in the south, and Ali in the west. In Sichuan, the most suitable habitat (18.83 × 104 km2) was located in Aba, Ganzi, and Liangshan. In Qinghai, the most suitable habitat (13.05 × 104 km2) mainly included Yushu in the southwest; Guoluo in the southeast; Haidong, Huangnan, Xining, and Hainan in the east; and Haixi in the west. In Gansu, the most suitable habitat (7.36 × 104 km2) was located in Gannan and Linxia in the southwest and Wuwei and Dingxi in the middle. In Yunnan, the most suitable habitat (1.53 × 104 km2) was distributed in Diqing in the northwest. Under future climate scenarios, the area of the most suitable habitat of E. granulosus showed an obvious expansion trend, with an increase of 44.64-70.76%. Trajectory trend of centroids showed that the most suitable habitat would move to the west in the future, and the increased areas were mainly located in the west of the current most suitable habitat. AUC values of the training data and test data were 0.936 ± 0.001 ~ 0.97 ± 0.006 and 0.912 ± 0.006 ~ 0.956 ± 0.015, respectively. The result can provide a theoretical basis for the prevention, monitoring, and early warning of echinococcosis in China.

The impact of natural environment on human alveolar echinococcosis: A township-level modeling study in Qinghai-Tibet Plateau.

Human alveolar echinococcosis (AE) is a lethal helminthic infection caused by the tapeworms Echinococcus multilocularis. The Qinghai-Tibet Plateau has the greatest endemicity of human AE globally, but the natural risk factors and its impact mechanism are still unclear. Generalized linear models and generalized additive models are used to select key linear and non-linear environmental factors associated with cases of AE. The interactive effect between different factors is identified using concurvity test. From fifty-nine variables analyzed, four key factors and one interaction term were identified associated with AE. Considering interaction terms between climatic and geographical landscape factors can significantly improve model fitting. Minimum winter precipitation, percentage of grassland cover, and minimum elevation have significant positive linear relationship with human AE incidence. The relationship between maximum summer precipitation and human AE is non-linear with high AE incidence associated with moderate precipitation. The interaction term of maximum summer precipitation and number of patches of grassland on human AE indicates that human AE incidence is highest when both factors were high. The climatic and landscape risk factors together are associated with the local transmission of human AE in Qinghai-Tibet Plateau. This study provides a scientific basis for human intervention in AE from fine-scale ecological environment.

Prevalence of stroke and associated risk factors: a population-based cross-sectional study from the Qinghai-Tibet Plateau of China.

BACKGROUND AND OBJECTIVES: The epidemiology of stroke at high altitudes has not been extensively studied, especially at heights of 4000 m and above. Thus, stroke prevention and treatment at high altitudes are challenging. We conducted a cross-sectional study to estimate the prevalence of stroke, the detection rate of individuals at high risk of stroke and the risk factors for stroke in the Qinghai-Tibet Plateau in China, a high altitude plateau that inhabits approximately 15 million people. DESIGN: A population-based cross-sectional study in the Qinghai-Tibet Plateau. SETTING: Data were collected from participants through face-to-face screening using a primary screening table. The table relied on the China National Stroke Screening and Prevention Project. PARTICIPANTS: A total of 10 700 residents aged ≥40 years and living on the Qinghai-Tibet Plateau for more than 6 months participated from January 2019 to December 2021. MAIN OUTCOME MEASURES: The primary screening table included basic demographic information, medical history information, personal lifestyle habits and physical examination information. RESULTS: A total of 10 056 people were included in the analysis. The prevalence of stroke was 2.3% (95% CI 2.0% to 2.6%), and the detection rate of individuals at high risk of stroke was 26.2% (95% CI 25.3% to 27.0%). The prevalence of stroke and the detection rate of individuals at high risk of stroke increased with altitude (p<0.01), and the prevalence of stroke at high altitudes was almost 2.2 times that at mid-altitudes (p<0.01). After full adjustments, age, residence, hypertension, family history of stroke and smoking were significantly associated with stroke (p<0.05). CONCLUSIONS: The prevalence of stroke, the related risk factors and the detection rate of high-risk individuals were clarified. The prevalence rates of hypertension, overweight or obesity and diabetes in the Qinghai-Tibet Plateau were all higher than the Chinese average. Higher-altitude exposure may be an independent risk factor for stroke.

Risk factors and SCN5A-H558R polymorphism for atrial fibrillation in Tibetans living at different altitudes.

Several studies have found associations of genes with atrial fibrillation (AF), including SCN5A-H558R. However, there are limited data of these associations among populations living at different altitudes. We investigated the relationship between the SCN5A-H558R polymorphism and AF in Tibetans living at different altitudes in Qinghai, China. General clinical and genotype data were obtained from 72 patients with AF and 109 non-AF (NAF) individuals at middle altitudes, and from 102 patients with AF and 143 NAF individuals at high altitudes. Multifactor logistic regression was performed to determine associations and AF risk factors. SCN5A-H558R genotypes differed significantly between the AF and NAF groups (P < .0125) and the G allele was an independent AF risk factor (P < .05) at both altitudes, with no significant differences according to altitude (P > .0125). At middle altitudes, age, red blood cell distribution width (RDW-SD), left atrial internal diameter (LAD), and G allele were independent AF risk factors. At high altitudes, age, smoking, hypertension, RDW-SD, free triiodothyronine, LAD, and G allele were independent AF risk factors (P < .05). The G allele of SCN5A-H558R might be an independent risk factor of AF both high and middle altitude, but there are some differences in other clinical risk factors of AF.

Societal drivers of human echinococcosis in China.

BACKGROUND: Echinococcosis is a parasitic zoonotic disease that threatens human health and economic development. In China, 370 counties are endemic for echinococcosis. Qinghai-Tibet Plateau has the most patients and people at risk. Therefore, analyzing the societal factors related to susceptibility to the disease is critical for efficient prevention and control of echinococcosis. METHODS: The demographic characteristics and lifestyle of echinococcosis cases were clustered using K-means cluster analysis to determine the main factors of risk of echinococcosis. RESULTS: Middle-aged and young people as well as those with a low education level and herdsmen are at risk of contracting echinococcosis. Nomadism, domestic and feral dogs in the surrounding environment, and drinking heavily polluted natural surface water are the main behavioral risk factors. The cystic echinococcosis (CE) and alveolar echinococcosis (AE) cluster analysis focused on female, middle-aged, and young people, winter settlement and summer nomadism, and domestic and feral dogs in the surrounding environment. There were significant differences in lifestyle between Qinghai-Tibet Plateau cases and non-Qinghai-Tibet-Plateau cases. CONCLUSION: According to the distribution of cases and CE and AE, this study identified the factors of risk of echinococcosis in the Qinghai-Tibet Plateau and non-Qinghai-Tibet Plateau. Adapted control techniques appropriate for the various epidemic areas should be established to serve as a reference for echinococcosis prevention.

Scoliosis among children in Qinghai-Tibetan Plateau of China: A cross-sectional epidemiological study.

Background: The average altitude of Qinghai-Tibetan Plateau is 4,500 m and most of the residents are Tibetan ethnicity. The purpose of this study was to investigate the prevalence of scoliosis and associated factors among children in this region through a scoliosis screening program. Methods: A cross-sectional study was preformed between May 2020 and December 2020 in Qinghai-Tibetan Plateau. A total of 9,856 children aged 6-17 years from schools and nearby villages were screened using visual inspection, the Adams forward-bending test, the angle of trunk rotation, and radiography. A self-designed questionnaire was used to collect demographic data. The prevalence of scoliosis and associated factors were analyzed. Results: The overall prevalence of scoliosis among children in Qinghai-Tibetan Plateau was 3.69%, with 5.38% for females and 2.11% for males. The prevalence of scoliosis was 3.50% in children resided below 4,500 m while 5.63% in those resided above 4,500 m (P = 0.001). The prevalence of congenital scoliosis (2.14 vs. 0.42%, P < 0.001) and neuromuscular scoliosis (0.34 vs. 0.07%, P = 0.041) were significantly higher in the altitude above 4,500 m. 50.00% of patients resided above 4,500 m were recommended for surgery while 16.24% in those resided below 4,500 m (P < 0.001). Independent associated factors were detected as female (OR = 2.217, 95 CI% 1.746-2.814, P < 0.001), BMI < 18.5 (OR = 1.767, 95 CI% 1.441-2.430, P = 0.005), altitude of residence ≥ 4,500 m (OR = 1.808, 95 CI% 1.325-2.483, P = 0.002), and sleep time < 8 h (OR = 2.264, 95 CI% 1.723-2.846, P = 0.001). Conclusion: The prevalence of scoliosis among children in Qinghai-Tibetan Plateau was 3.69%. With increasing altitudes, the prevalence of scoliosis and its major type were different from that at lower altitudes. Female, BMI < 18.5, altitude of residence ≥ 4,500 m, and sleep time < 8 h were independently associated with the prevalence of this disease. Early screening should be carried out before the age of 7 years, especially in the high-altitude, underdeveloped, and rural areas.

Dietary and drinking water intake of essential trace elements in a typical Kashin-Beck disease endemic area of Tibet, China.

BACKGROUND: Essential trace elements (ETEs), such as copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), selenium (Se), zinc (Zn), are very important elements for human health. METHODS: In this study, 89 drinking water samples and 85 highland barleys were collected from 48 villages in 11 townships, and the average daily dose (ADD) of ETEs were calculated, in addition, health effects of ETEs to rural residents in Luolong County, a typical Kashin-Beck disease (KBD) endemic area in Tibet, were assessed. RESULTS: The mean concentrations of Cu, Fe, Mn, Mo, Se, Zn in drinking water were 0.278 ± 0.264 µg·kg-1, 0.766 ± 0.312 µg·kg-1, 0.411 ± 0.526 µg·kg-1, 0.119 ± 0.223 µg·kg-1, 0.155 ± 0.180 µg·kg-1, and 0.804 ± 1.112 µg·kg-1, respectively; and mean concentrations of Cu, Fe, Mn, Mo, Se and Zn in highland barley were 3.550 ± 0.680 mg·kg-1, 81.17 ± 38.14 mg·kg-1, 14.03 ± 1.42 mg·kg-1, 0.350 ± 0.200 mg·kg-1, 0.0028 ± 0.0056 mg·kg-1, and 23.58 ± 3.10 mg·kg-1, respectively. The ADD of Cu in the study area was appropriate; the ADD of Fe and Mn in each township were higher than the maximum oral reference dose recommended by the National Health Commission of China, indicating that Fe and Mn had non-carcinogenic health risks; the ADD of Mo and Zn in 36.36% and 54.55% of the townships exceeded the maximum oral reference dose; and 72.73% of the townships had insufficient ADD of Se. The ADD of Mo, Cu and Se in different townships was significantly correlated with the prevalence of KBD. CONCLUSIONS: Therefore, in order to prevent and control the prevalence of KBD and ensure the health of local residents, it is necessary to reduce the intake of high concentrations of Fe, Mn and Zn in diet, as well as increase the intake of Mo, Cu, especially Se.