Comparison of Muscle Density in Middle-Aged and Older Chinese Adults Between a High-Altitude Area (Kunming) and a Low-Altitude Area (Beijing)

Using ML techniques to predict extubation outcomes for patients with central nervous system injuries in the Yun-Gui Plateau

No predictive models have been reported for tracheostomy extubation success in plateau region rehabilitation departments. Hence, the primary objective of this retrospective study was to evaluate the predictive capabilities of different models for extubation outcomes in CNS injury patients in plateau rehabilitation departments, as well as investigate the influence of clinical features on these outcomes. Data were collected from 501 adult tracheostomy patients in the Department of Rehabilitation Medicine, including 196 successful extubations. Logistic regression was employed to identify the significant features linked to extubation outcomes from a pool of 31 variables. A total of eight independent models and a weighted posterior voting ensemble model were developed. Hyperparameter optimization and tenfold cross-validation were used to assist in choosing model parameters. Random forest (ACC = 84.15, AUC = 0.85), extra trees (83.17%, 0.87), K-NN (82.18%, 0.85), and gradient boosting (81.19%, 0.85) performed well. An ensemble model (85.15%, 0.87) combining random forest, Gaussian naive Bayes, and K-NN via the WPV method was developed. Dysphagia and low GCS scores have been linked to increased difficulty in extubation, as indicated by SHAP values and previous studies. Moreover, there could be a relationship between chronic inflammation and albumin levels in patients, which may collectively impact extubation success. This study evaluated the effectiveness of conventional models for predicting extubation outcomes and analyzed the factors influencing extubation results at high altitudes, laying the groundwork for clinical use and future research. Nevertheless, further research will see advantages in using multicentric approaches and broadening clinical indicators.

Association between hip fracture fixation methods and bone mineral density T-value in middle-aged and elderly patients with hip fractures

OBJECTIVE

To examine the association of proximal femoral nail anti-rotation (PFNA) and dynamic hip screw (DHS) with bone mineral density T-value (BMDT) in middle-aged and elderly patients suffering from hip fractures.

METHODS

Clinical data were collected from 110 patients with hip fractures who underwent internal fixation surgery between October 2020 and June 2021. Patients treated with DHS were included in the control group, and those treated with PFNA were classified into the observation group. The disparity in BMDT between the two groups was assessed. Patients were further divided into two groups based on the median BMDT at 6 months post-surgery: a high BMDT group (BMDT>-1.1 SD) and a low BMDT group (BMDT≤-1.1 SD). Factors influencing BMDT were analyzed.

RESULTS

Repeated measures ANOVA showed that BMDT in the observation group was higher than that in the control group at 7 days, 1 month, 3 months, and 6 months after the surgery (between-group effect: F=258.400, P<0.001). BMDT in both groups increased with time but remained lower than pre-surgery levels (time effect: F=28.760, P<0.001), with an interaction between group and time (F=6.478, P<0.05). Correlation analysis showed a significant correlation between internal fixation techniques and BMDT at 7 days, 1 month, 3 months, 6 months after the surgery (P<0.05). Logistic regression analysis showed that advanced age and a higher VAS score at 72 hours post-surgery were risk factors for low BMDT at 6 months post-surgery, while PFNA was a protective factor (all P<0.05).

CONCLUSION

Compared to DHS, PFNA significantly improves BMDT in middle-aged and elderly patients following hip fracture surgery, promoting better early-stage recovery. PFNA should be prioritized in clinical practice to enhance postoperative outcomes.

Analysis of medication treatment for women with osteoporosis: A real-world retrospective study from Chinese tertiary grade A hospital

Purpose

This study aimed to analyze the current medication treatment status for women with osteoporosis (OP) based on real-world prescription data from 2016 to 2021 in Chinese nine cities' tertiary Grade A hospital and systematically describe the medication treatment patterns in women with OP.

Methods

Prescription information for female OP patients in nine cities (Beijing, Shanghai, Guangzhou, Hangzhou, Tianjin, Zhengzhou, Chengdu, Shenyang, Harbin) was extracted from the Hospital Prescription Analysis Collaboration Project Database of the Hospital Pharmacy Professional Committee of the Chinese Pharmaceutical Association. Statistical analysis was conducted to evaluate demographic characteristics and medication treatment patterns.

Results

A total of 669,505 prescriptions for medication treatment of female OP patients were included in this study. The majority of patients were aged 60 to 99 years (69.79 %) followed by 50 to 59 years (18.81 %) and 40 to 49 years (6.69 %). Geographically, the highest concentration of patients was in North China (Beijing, Tianjin) (43.05 %) followed by East China (Shanghai, Hangzhou) (31.43 %). The top three prescribed medications were active vitamin D and its analogs (40.78 %), calcium supplements (32.51 %), and bisphosphonates (18.75 %). The prescription frequency of menopausal hormone therapy (MHT) was 0.31 %. The proportion of female OP patients receiving monotherapy and two drug combinations therapy is equivalent (about 37 %).

Conclusion

The diagnosis and treatment of female OP patients in China showed regional variations. The most commonly prescribed medications for this population were calcitriol, calcium carbonate with vitamin D3, and alendronate sodium with vitamin D3. The use of MHT was relatively limited.

Factors Affecting Carotid Artery Stenosis in the Elderly Living at High Altitudes

BACKGROUND

Factors affecting carotid artery stenosis have been generally investigated. However, considering the protective effect of altitude, studies on elderly individuals at high altitudes are few. Our aim is to investigate the systematic adaptive changes caused by high-altitude exposure through the causes of carotid artery stenosis.

MATERIALS AND METHODS

Carotid Doppler ultrasound was performed on 250 patients over the age of 50 years. The patients' age, gender, height, weight, smoking history, place of residence, and presence of comorbidities were questioned. Those with diabetes, hypertension, hyperlipidemia, and coronary disease were excluded from the study. Those who did not reside at high altitudes were excluded from the study. One hundred and thirty-five patients were included in the study. Carotid artery Doppler findings and biochemical parameters were recorded. Factors affecting stenosis in the carotid arteries were compared.

RESULTS

In our study, the factors affecting carotid stenosis were determined to be age, gender, presence of plaque, plaque type, and mean carotid intima-media thickness (CIMT). The mean CIMT of the patients was calculated as 0.71±0.14 mm. The mean CIMT measurement level was significantly higher in patients with plaque in the carotid artery (p<0.05). According to receiver operating characteristic curves, CIMT values higher than 0.72 mm increase plaque and stenosis formation in the common carotid artery (CCA) and internal carotid artery (ICA) in elderly people living at high altitudes (p<0.05, area under the curve [AUC]: 0.71-0.83).

CONCLUSIONS

The most important factors affecting carotid stenosis in individuals living at high altitudes are age, gender, CIMT, plaque, and plaque type. When soft plaques were detected, the risk of stenosis was found to be higher than in calcific plaques. Additionally, the number of factors affecting stenosis was greater on the left (ICA). This suggests that the left carotid system is more vulnerable. It can be said that in elderly individuals living at high altitudes, a CIMT higher than 0.72 mm is a cutoff value in the presence of plaque and stenosis in the carotid arteries.

High-altitude exposure decreases bone mineral density and its relationship with gut microbiota: Results from the China multi-ethnic cohort (CMEC) study

BACKGROUND

Geographic altitude is a potent environmental factor for human microbiota and bone mineral density. However, little evidence exists in population-based studies with altitude diversity ranges across more than 3000 m. This study assessed the associations between a wide range of altitudes and bone mineral density, as well as the potential mediating role of microbiota in this relationship.

METHODS

A total of 99,556 participants from the China Multi-Ethnic Cohort (CMEC) study were enrolled. The altitude of each participant was extracted from global Shuttle Radar Topography Mission (SRTM) 4 data. Bone mineral density was measured by calcaneus quantitative ultrasound index (QUI). Stool samples were collected for 16S rRNA gene sequencing (n = 1384). The metabolites of gut microbiota, seven kinds of short-chain fatty acids (SCFAs), were detected by gas chromatography-mass spectrometry (GC-MS, n = 128). After screening, 73,974 participants were selected for the "altitude-QUI" analysis and they were placed into the low-altitude (LA) and high-altitude (HA) groups. Additionally, a subgroup (n = 1384) was further selected for the "altitude-microbiota-QUI" analysis. Multivariate linear regression models and mediation analyses were conducted among participants.

RESULTS

A significant negative association between high-altitude and QUI was obtained (mean difference = -0.373 standard deviation [SD], 95% confidence interval [CI]: -0.389, -0.358, n = 73,974). The same negative association was also observed in the population with microbiota data (mean difference = -0.185 SD, 95%CI: -0.360, -0.010, n = 1384), and a significant mediating effect of Catenibacteriumon on the association between altitude and QUI (proportion mediated = 25.2%, P = 0.038) was also noticed. Additionally, the acetic acid, butyric acid, and total amount of seven SCFAs of the low-altitude group were significantly higher than that of the high-altitude group (P < 0.05).

CONCLUSION

High-altitude exposure may decrease bone mineral density in adults, thus increasing the risk of osteoporosis. The modulation of gut microbiota may be a potential strategy for alleviating the decrease of bone mineral density.

Normative reference data for body composition in healthy indigenous populations on the Qinghai-Tibet Plateau

Body composition represents an important aspect of physical fitness and has received increasing attention in recent years. The present study was designed and conducted to provide reference values for age-, sex-, and altitude-specific body composition for healthy indigenous Tibetan adults living on the Qinghai-Tibet Plateau, which has not yet been studied. A cross-sectional survey was conducted among 2,356 healthy Tibetan adults (1,433 females and 923 males) living on the Qinghai-Tibet Plateau for generations. The body composition of the participants was measured by bioelectrical impedance analysis (BIA). The measurements included weight, basal metabolic rate (BMR), fat-free mass (FFM), skeletal muscle mass (SMM), protein mass (PM), bone mass (BM), fat mass (FM), percentage of body fat (PBF), subcutaneous fat mass (SFM), visceral fat mass (VFM), total body water (TBW), intracellular water (ICW), and extracellular water (ECW). Overall, males had greater FFM, SMM, PM, BM, and water mass, whereas females were high in fat mass. Participants from plains generally had higher body composition values, and PM, BM, FM and body water values decreased with increasing altitude, with the lowest values found in >4,000 m Shigatse. FFM, SMM, PM, and BM tended to decrease with increasing age, whereas fat mass and ECW tended to increase with increasing age. This study provides the first normative reference data of body composition for healthy indigenous individuals on the Qinghai-Tibet Plateau. These datasets are important for future research related to body composition. A considerable decrease in body composition values in > 4,000 m-altitude areas suggested that body composition cutoff values should be established by altitude. Age-, sex-, and altitude-specific alterations in body composition values also inform the prevention and amendment of abnormal body composition changes and resultant health complications.

Screening of osteoporosis and sarcopenia in individuals aged 50 years and older at different altitudes in Yunnan province: Protocol of a longitudinal cohort study

INTRODUCTION

Musculoskeletal system gradually degenerates with aging, and a hypoxia environment at a high altitude may accelerate this process. However, the comprehensive effects of high-altitude environments on bones and muscles remain unclear. This study aims to compare the differences in bones and muscles at different altitudes, and to explore the mechanism and influencing factors of the high-altitude environment on the skeletal muscle system.

METHODS

This is a prospective, multicenter, cohort study, which will recruit a total of 4000 participants over 50 years from 12 research centers with different altitudes (50m~3500m). The study will consist of a baseline assessment and a 5-year follow-up. Participants will undergo assessments of demographic information, anthropomorphic measures, self-reported questionnaires, handgrip muscle strength assessment (HGS), short physical performance battery (SPPB), blood sample analysis, and imaging assessments (QCT and/or DXA, US) within a time frame of 3 days after inclusion. A 5-year follow-up will be conducted to evaluate the changes in muscle size, density, and fat infiltration in different muscles; the muscle function impairment; the decrease in BMD; and the osteoporotic fracture incidence. Statistical analyses will be used to compare the research results between different altitudes. Multiple linear, logistic regression and classification tree analyses will be conducted to calculate the effects of various factors (e.g., altitude, age, and physical activity) on the skeletal muscle system in a high-altitude environment. Finally, a provisional cut-off point for the diagnosis of sarcopenia in adults at different altitudes will be calculated.

ETHICS AND DISSEMINATION

The study has been approved by the institutional research ethics committee of each study center (main center number: KHLL2021-KY056). Results will be disseminated through scientific conferences and peer-reviewed publications, as well as meetings with stakeholders.

CLINICAL TRIAL REGISTRATION NUMBER

http://www.chictr.org.cn/index.aspx, identifier ChiCTR2100052153.