Low muscle mass and malnutrition are prevalent conditions among adults of all ages, with any body weight or body mass index, and with acute or chronic conditions, including COVID-19. This article synthesizes the latest research advancements in muscle health and malnutrition, and their impact on immune function, and clinical outcomes. We provide a toolkit of illustrations and scientific information that healthcare professionals can use for knowledge translation, educating patients about the importance of identifying and treating low muscle mass and malnutrition. We focus on the emerging evidence of mitochondrial dysfunction in the context of aging and disease, as well as the cross-talk between skeletal muscle and the immune system. We address the importance of myosteatosis as a component of muscle composition, and discuss direct, indirect and surrogate assessments of muscle mass including ultrasound, computerized tomography, deuterated creatine dilution, and calf circumference. Assessments of muscle function are also included (handgrip strength, and physical performance tests). Finally, we address nutrition interventions to support anabolism, reduce catabolism, and improve patient outcomes. These include protein and amino acids, branched-chain amino acids, with a focus on leucine; β-hydroxy-β-methylbutyrate (HMB), vitamin D; n-3 polyunsaturated fatty acids (n-3 PUFA), polyphenols, and oral nutritional supplements. We concluded with recommendations for clinical practice and a call for action on research focusing on evaluating the impact of body composition assessments on targeted nutrition interventions, and consequently their ability to improve patient outcomes.

As many as two of every three major surgery patients are malnourished preoperatively – a diagnosis rarely made and treated even less frequently. Unfortunately, perioperative malnutrition is perhaps the least often identified surgical risk factor and is among the most treatable to improve outcomes. Two important perioperative nutrition guidelines were published recently. Both emphasize nutrition assessment as an essential component of preoperative screening. The recently published perioperative nutrition screen (PONS) readily identifies patients at malnutrition risk, allowing for preoperative nutritional optimization. The use of computerized tomography scan and ultrasound lean body mass (LBM) evaluation to identify sarcopenia associated with surgical risk and guide nutrition intervention is garnering further support. Preoperative nutrition optimization in malnourished patients, use of immunonutrition in all major surgery, avoidance of preoperative fasting, inclusion of postoperative high-protein nutritional supplements, and early postoperative oral intake have all recently been shown to improve outcomes and should be utilized. The recent publication of new surgical nutrition guidelines, the PONS score, and use of LBM assessments will allow better identification and earlier intervention on perioperative malnutrition. It is essential that in the future no patient undergoes elective surgery without nutrition screening and nutrition intervention when malnutrition risk is identified.

Recent advances in wearable technology through convenient and cuffless systems will enable continuous, noninvasive monitoring of blood pressure (BP), heart rate, and heart rhythm on both longitudinal 24‐hour measurement scales and high‐frequency beat‐to‐beat BP variability and synchronous heart rate variability and changes in underlying heart rhythm. Clinically, BP variability is classified into 4 main types on the basis of the duration of monitoring time: very‐short‐term (beat to beat), short‐term (within 24 hours), medium‐term (within days), and long‐term (over months and years). BP variability is a strong risk factor for cardiovascular diseases, chronic kidney disease, cognitive decline, and mental illness. The diagnostic and therapeutic value of measuring and controlling BP variability may offer critical targets in addition to lowering mean BP in hypertensive populations.

Background: Nonalcoholic fatty liver disease (NAFLD) and heart failure (HF) are increasing in prevalence. The independent association between NAFLD and downstream risk of HF and HF subtypes (HF with preserved ejection fraction and HF with reduced ejection fraction) is not well established. Methods and Results: This was a retrospective, cohort study among Medicare beneficiaries. We selected Medicare beneficiaries without known prior diagnosis of HF. NAFLD was defined using presence of 1 inpatient or 2 outpatient claims using International Classification of Diseases, Ninth Revision, Clinical Modification ( ICD‐9‐CM ), claims codes. Incident HF was defined using at least 1 inpatient or at least 2 outpatient HF claims during the follow‐up period (October 2015–December 2016). Among 870 535 Medicare patients, 3.2% (N=27 919) had a clinical diagnosis of NAFLD. Patients with NAFLD were more commonly women, were less commonly Black patients, and had a higher burden of comorbidities, such as diabetes, obesity, and kidney disease. Over a mean 14.3 months of follow‐up, patients with (versus without) baseline NAFLD had a significantly higher risk of new‐onset HF in unadjusted (6.4% versus 5.0%; P <0.001) and adjusted (adjusted hazard ratio [HR] [95% CI], 1.23 [1.18–1.29]) analyses. Among HF subtypes, the association of NAFLD with downstream risk of HF was stronger for HF with preserved ejection fraction (adjusted HR [95% CI], 1.24 [1.14–1.34]) compared with HF with reduced ejection fraction (adjusted HR [95% CI], 1.09 [0.98–1.2]). Conclusions: Patients with NAFLD are at an increased risk of incident HF, with a higher risk of developing HF with preserved ejection fraction versus HF with reduced ejection fraction. The persistence of an increased risk after adjustment for clinical and demographic factors suggests an epidemiological link between NAFLD and HF beyond the basis of shared risk factors that requires further investigation.

Purpose of review: To help guide metabolic support in critical care, an understanding of patients’ nutritional status and risk is important. Several methods to monitor lean body mass are increasingly used in the ICU and knowledge about their advantages and limitations is essential. Recent findings: Computed tomography scan analysis, musculoskeletal ultrasound, and bioelectrical impedance analysis are emerging as powerful clinical tools to monitor lean body mass during ICU stay. Accuracy, expertise, ease of use at the bedside, and costs are important factors which play a role in determining which method is most suitable. Exciting new research provides an insight into not only quantitative measurements, but also qualitative measurements of lean body mass, such as infiltration of adipose tissue and intramuscular glycogen storage. Summary: Methods to monitor lean body mass in the ICU are under constant development, improving upon bedside usability and offering new modalities to measure. This provides clinicians with valuable markers with which to identify patients at high nutritional risk and to evaluate metabolic support during critical illness.