Gut microbiota in sarcopenia and heart failure

Molecular mechanisms underlying sarcopenia in heart failure

The loss of skeletal muscle, also known as sarcopenia, is an aging-associated muscle disorder that is disproportionately present in heart failure (HF) patients. HF patients with sarcopenia have poor outcomes compared to the overall HF patient population. The prevalence of sarcopenia in HF is only expected to grow as the global population ages, and novel treatment strategies are needed to improve outcomes in this cohort. Multiple mechanistic pathways have emerged that may explain the increased prevalence of sarcopenia in the HF population, and a better understanding of these pathways may lead to the development of therapies to prevent muscle loss. This review article aims to explore the molecular mechanisms linking sarcopenia and HF, and to discuss treatment strategies aimed at addressing such molecular signals.

Prevalence of sarcopenia and its association with clinical outcomes in heart failure: An updated meta-analysis and systematic review

BACKGROUND

Sarcopenia is thought to be strongly associated with heart failure, but meta-analyses with sufficient samples are still lacking to accurately address its clinical situation.

HYPOTHESIS

Sarcopenia has a high prevalence in patients with heart failure and is closely related to adverse clinical outcomes.

METHODS

Relevant databases were systematically searched in October 2021 and updated in July 2022. The data with high heterogeneity were combined with random effects model.

RESULTS

Twenty-one studies with 68,556 HF patients were included. The combined prevalence of sarcopenia in HF patients was 31%. Subgroup analysis found that the prevalence of sarcopenia in HF patients was 35% in Asia, 31% in Europe, 25% in the Americas, 31% in people aged ≥65 years, 25% in people with age <65 years, 28% in HF with reduced ejection fraction (HFrEF) patients and 18% in HF with preserved ejection fraction (HFpEF) patients. In addition, our analysis shows that sarcopenia in patients with HF is associated with an increased risk of poor prognosis, with a combined hazard ratio [HR] of 1.64 (95% confidence interval [CI] = 1.20-5.25), sarcopenia was also associated with poor outcomes in HFrEF patients with pooled HR of 2.77 (95% CI = 1.29-5.95). However, it was not associated with poor outcomes in HFpEF patients with pooled HR of 1.61 (95% CI = 0.82-3.16).

CONCLUSIONS

The prevalence of sarcopenia is high in HF patients, and patients with HF, particularly those with reduced ejection fraction, are at high risk of adverse outcomes from sarcopenia. Therefore, early identification and intervention for sarcopenia were beneficial for improving the prognosis of HF patients.

New features of parenteral nutrition in home care and acute care setting for the older population

PURPOSE OF REVIEW

The intent of this review is to highlight any recent changes in the delivery of parenteral nutrition to the geriatric population. The percentage of patients in the geriatric age group increases clinical awareness of the potential risks and benefits of appropriate parenteral nutrition delivery, which is crucial to well tolerated and optimum outcomes.

RECENT FINDINGS

The major recent finding is the increased awareness of risk of parenteral nutrition in the elderly population.

SUMMARY

The implications of this very brief review expose the need for further focused studies to better clarify the specifics of parenteral nutrition in this vulnerable ageing population. The importance of nutritional risk assessment cannot be overstated. With the rapidly expanding volume of geriatric population, the need for more data to better understand the delicate balance in parenteral nutrition therapy for both the acute care setting and home parenteral population is needed.

Association between Microbiome-Related Human Genetic Variants and Fasting Plasma Glucose in a High-Cardiovascular-Risk Mediterranean Population

Background and Objectives: The gut microbiota has been increasingly recognized as a relevant factor associated with metabolic diseases. However, directly measuring the microbiota composition is a limiting factor for several studies. Therefore, using genetic variables as proxies for the microbiota composition is an important issue. Landmark microbiome–host genome-wide association studies (mbGWAS) have identified many SNPs associated with gut microbiota. Our aim was to analyze the association between relevant microbiome-related genetic variants (Mi-RSNPs) and fasting glucose and type 2 diabetes in a Mediterranean population, exploring the interaction with Mediterranean diet adherence. Materials and Methods: We performed a cross-sectional study in a high-cardiovascular-risk Mediterranean population (n = 1020), analyzing the association of Mi-RSNPs (from four published mbGWAS) with fasting glucose and type 2 diabetes. A single-variant approach was used for fitting fasting glucose and type 2 diabetes to a multivariable regression model. In addition, a Mendelian randomization analysis with multiple variants was performed as a sub-study. Results: We obtained several associations between Mi-RSNPs and fasting plasma glucose involving gut Gammaproteobacteria_HB, the order Rhizobiales, the genus Rumminococcus torques group, and the genus Tyzzerella as the top ranked. For type 2 diabetes, we also detected significant associations with Mi-RSNPs related to the order Rhizobiales, the family Desulfovibrionaceae, and the genus Romboutsia. In addition, some Mi-RSNPs and adherence to Mediterranean diet interactions were detected. Lastly, the formal Mendelian randomization analysis suggested combined effects. Conclusions: Although the use of Mi-RSNPs as proxies of the microbiome is still in its infancy, and although this is the first study analyzing such associations with fasting plasma glucose and type 2 diabetes in a Mediterranean population, some interesting associations, as well as modulations, with adherence to the Mediterranean diet were detected in these high-cardiovascular-risk subjects, eliciting new hypotheses.