Does an Association among Sarcopenia and Metabolic Risk Factors Exist in People Older Than 65 Years? A Systematic Review and Meta-Analysis of Observational Studies

Relationships of Fat Mass Index and Fat-Free Mass Index with Low-Density Lipoprotein Cholesterol Levels in the Tohoku Medical Megabank Community-Based Cohort Study

AIMS

Although fat mass (FM) and fat-free mass (FFM) have an impact on lipid metabolism, the relationship between different body composition phenotypes and lipid profiles is still unclear. By dividing the FM and FFM by the square of the height, respectively, the fat mass index (FMI) and fat-free mass index (FFMI) can be used to determine the variations in body composition. This study aimed to investigate the relationship of combined FMI and FFMI with low-density lipoprotein cholesterol (LDL-C) levels.

METHODS

This cross-sectional study comprised 5,116 men and 13,630 women without cardiovascular disease and without treatment for hypertension, and diabetes. Following sex-specific quartile classification, FMI and FFMI were combined into 16 groups. Elevated LDL-C levels were defined as LDL-C ≥ 140 mg/dL and/or dyslipidemia treatment. Multivariable logistic regression models were used to examine the relationships between combined FMI and FFMI and elevated LDL-C levels.

RESULTS

Overall, elevated LDL-C levels were found in 1,538 (30.1%) men and 5,434 (39.9%) women. In all FFMI subgroups, a higher FMI was associated with elevated LDL-C levels. Conversely, FFMI was inversely associated with elevated LDL-C levels in most FMI subgroups. Furthermore, the groups with the highest FMI and lowest FFMI had higher odds ratios for elevated LDL-C levels than those with the lowest FMI and highest FFMI.

CONCLUSIONS

Regardless of FFMI, FMI was positively associated with elevated LDL-C levels. Conversely, in the majority of FMI subgroups, FFMI was inversely associated with elevated LDL-C levels.

Bezafibrate attenuates immobilization-induced muscle atrophy in mice

Muscle atrophy due to fragility fractures or frailty worsens not only activity of daily living and healthy life expectancy, but decreases life expectancy. Although several therapeutic agents for muscle atrophy have been investigated, none is yet in clinical use. Here we report that bezafibrate, a drug used to treat hyperlipidemia, can reduce immobilization-induced muscle atrophy in mice. Specifically, we used a drug repositioning approach to screen 144 drugs already utilized clinically for their ability to inhibit serum starvation-induced elevation of Atrogin-1, a factor related to muscle atrophy, in myotubes in vitro. Two candidates were selected, and here we demonstrate that one of them, bezafibrate, significantly reduced muscle atrophy in an in vivo model of muscle atrophy induced by leg immobilization. In gastrocnemius muscle, immobilization reduced muscle weight by an average of ~ 17.2%, and bezafibrate treatment prevented ~ 40.5% of that atrophy. In vitro, bezafibrate significantly inhibited expression of the inflammatory cytokine Tnfa in lipopolysaccharide-stimulated RAW264.7 cells, a murine macrophage line. Finally, we show that expression of Tnfa and IL-1b is induced in gastrocnemius muscle in the leg immobilization model, an activity significantly antagonized by bezafibrate administration in vivo. We conclude that bezafibrate could serve as a therapeutic agent for immobilization-induced muscle atrophy.

The relationship between temporal muscle thickness and triglyceride glucose index in sarcopenia with mortality and third-month functional outcomes in patients after acute stroke

Especially in recent years, temporal muscle thickness has been used as an important parameter for sarcopenia in neurological disorders. In addition, triglyceride glucose index was evaluated separately in studies conducted in terms of coronary diseases, diabetes, high blood pressure, body mass index and acute stroke. In this clinical study, unlike the others, both temporal muscle thickness and triglyceride glucose index were evaluated together in acute stroke patients in terms of sarcopenia. We aimed to investigate the relationship between temporal muscle thickness and triglyceride glucose index, which is atherosclerotic index, with mortality and 3rd month functional outcomes in acute stroke patients. In this retrospective study, 147 patients admitted to Ankara City Hospital with the diagnosis of acute ischemic stroke between January 2021 and September 2022 were evaluated. Fasting triglyceride glucose indexes of the patients were calculated. The temporal muscle thickness measurement of the patients was performed by the radiologist using computed tomography images. Those who scored 3 or higher on the modified Rankin Scale (mRS) at the third month were considered to have poor functional outcome. A significant cutoff point was found for estimating mortality for the temporal muscle thickness parameter [area under the curve for a receiver operating characteristic curve (AUC) = 0.636; P = .012]. The cutoff point was obtained as ≤ 5.2. Sensitivity value was 65%, specificity value was 65%, the positive predictive value (PPV) value was 42.62% and the negative predictive value (NPV) value was 82.28%. Similarly, for the triglyceride glucose index parameter, there was a significant cutoff point in estimating mortality (AUC = 0.673; P = .003). The cutoff point was obtained as ≥ 8.23. Sensitivity value was 91.18%, specificity value was 13%, PPV value was 26.96% and NPV value was 81%. Temporal muscle thickness and triglyceride glucose index parameters were found to be statistically important parameters of sarcopenia. It was concluded that the evaluation of these 2 parameters in terms of both mortality and sarcopenia in acute stroke patients is important in the evaluation of neurological and cardiac disorders.