Serum iron level is independently associated with sarcopenia: a retrospective study.

Sarcopenia greatly reduces the quality of life of the elderly, and iron metabolism plays an important role in muscle loss. This study aimed to investigate the association between iron status and sarcopenia. A total of 286 adult patients hospitalized between 2019 and 2021 were included in this study, of which 117 were diagnosed with sarcopenia. Serum iron, total iron binding capacity (TIBC), transferrin, and transferrin saturation levels were compared between groups with and without sarcopenia and were included in the logistic analyses, with significant variables further included in the logistic regression model for the prediction of sarcopenia. Serum iron, TIBC, and transferrin levels decreased significantly in the sarcopenia group (p < 0.05), and were negatively associated with handgrip strength, relative skeletal muscle index, and multiple test performances (p < 0.05). Multivariate logistic analysis showed that sex, age, body mass index (BMI), and serum iron level were independent risk factors for sarcopenia. In the final logistic regression model, male sex (odds ratio [OR] 3.65, 95% confidence interval [CI] 1.67-7.98), age > 65 years (OR 5.40, 95% CI 2.25-12.95), BMI < 24 kg/m2 (OR 0.17, 95% CI 0.08-0.36), and serum iron < 10.95 µmol/L (OR 0.39, 95% CI 0.16-0.93) were included. Our study supported the impact of iron metabolism on muscle strength and performance.

The association of lipid metabolism and sarcopenia among older patients: a cross-sectional study.

Sarcopenia has become a heavy disease burden among the elderly. Lipid metabolism was reported to be involved in many degenerative diseases. This study aims to investigate the association between dysregulated lipid metabolism and sarcopenia in geriatric inpatients. This cross-sectional study included 303 patients aged ≥ 60, of which 151 were diagnosed with sarcopenia. The level of total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), homocysteine (HCY), BMI, and fat percentage, were compared between sarcopenia and non-sarcopenia patients. The Spearman correlation coefficient was used to estimate the association between sarcopenia and the level of lipid metabolism. To determine risk factors related to sarcopenia, a multivariate logistic regression analysis was carried out. Risk prediction models were constructed based on all possible data through principal component analysis (PCA), Logistic Regression (LR), Support Vector Machine (SVM), k-Nearest Neighbor (KNN), and eXtreme Gradient Boosting (XGboost). We observed rising prevalence of sarcopenia with increasing age, decreasing BMI, and fat percentage (p < 0.001, Cochran Armitage test). Multivariate logistic regression analysis revealed sarcopenia's risk factors, including older age, male sex, lower levels of BMI, TC, and TG, and higher levels of LDL and HCY (p < 0.05). The sarcopenia risk prediction model showed the risk prediction value of sarcopenia, with the highest area under the receiver operating curve (AUC) of 0.775. Our study provided thorough insight into the risk factors associated with sarcopenia. It demonstrated that an increase in lipid metabolism-related parameters (BMI, TG, TC), within normal reference ranges, may be protective against sarcopenia. The present study can illuminate the direction and significance of lipid metabolism-related factors in preventing sarcopenia.

Factors affecting sarcopenia in older patients with chronic diseases.

BACKGROUND: Sarcopenia is an age-related disease characterized by a progressive loss of systemic muscle mass and/or decreased muscle strength and physical function. The occurrence of sarcopenia in patients with chronic diseases will not only cause further deterioration of diseases and adverse clinical outcomes, but also lead to high medical cost, suggesting a necessity and a great significance to explore the associated factors of sarcopenia in chronic patients in order to improve their quality of life. This study aimed to investigate factors affecting sarcopenia among older hospitalized patients with chronic diseases. METHODS: A total of 121 older patients with chronic diseases admitted to the Department of Geriatrics of Affiliated Kunshan Hospital of Jiangsu University from May 2019 to April 2021 were enrolled. According to the diagnostic criteria of sarcopenia formulated by the Asian Working Group for Sarcopenia (AWGS), the subjects were divided into a sarcopenia group (n=57) and a non-sarcopenia group (n=64). We analyzed the associated factors including bone mineral density, nutritional biomarkers, hormone levels and inflammatory cytokines. RESULTS: Compared to the non-sarcopenia group, the sarcopenia group was of older average age (P<0.001), exhibited a lower body mass index (BMI) (P<0.001), a lower bone mineral density (BMD) of the femoral neck (P<0.01), and a higher incidence of osteoporosis. In terms of hematology, the sarcopenia group exhibited significantly lower serum iron and zinc levels (both P<0.05), a higher growth hormone (GH) level (P<0.05), a significantly lower IGF-1 level (P<0.01), and a lower level of iron (P<0.01). Poor nutritional status (assessed via measurement of albumin and prealbumin levels) positively correlated with sarcopenia (P<0.01). CONCLUSIONS: Sarcopenia is closely associated with aging, and has a close relationship with osteoporosis. Anemia, malnutrition, vitamin and trace element deficiencies, changes in hormone levels, and chronic inflammation are correlated with sarcopenia. Patients with these features above call for the screenig of sarcopenia. Additionally, these characteristics may help providing clues for further research on the pathogenesis and risk factors of sarcopenia, along with disease prevention and intervention.