Osteosarcopenic obesity (OSO) syndrome describes the simultaneous deterioration of bone, muscle and excess fat, resulting in reduced functionality and systemic metabolic dysregulation. The key component contributing to this may be ectopic fat in the viscera, bone and muscle. OSO research to date is summarized, and the revised criteria for its identification for research purposes are reviewed and proposed, including new criteria to assess visceral fat in males and females. Finally, nutritional and physical activity recommendations are consolidated into a treatment algorithm, which can be validated in future studies and which may also be applied to preventative management.

Chronic stress and low-grade chronic inflammation (LGCI) are key underlying factors for many diseases, including bone and body composition impairments. Objectives of this narrative review were to examine the mechanisms by which chronic stress and LGCI may influence osteosarcopenic adiposity (OSA) syndrome, originally named as ostoesarcopenic obesity (OSO). We also examined the crucial nutrients presumed to be affected by or cause of stress and inflammation and compared/contrasted them to those of our prehistoric ancestors. The evidence shows that stress (particularly chronic) and its related inflammatory processes, contribute to osteoporosis, sarcopenia, and adiposity ultimately leading to OSA as a final and most deranged state of body composition, commencing at the mesenchymal cell lineage disturbance. The foods/nutrients consumed by modern humans, as well as their altered lifestyle, also contribute to stress, LGCI and subsequently to OSA. The processes can also go in opposite direction when stress and inflammation impact nutritional status, particularly some micronutrients’ levels. While nutritional management of body composition and LGCI have been studied, the nutrients (and their quantities) most affected by stressors and those which may act toward the alleviation of stressful state, ultimately leading to better body composition outcomes, need to be elucidated.

Our study suggests that 'osteosarcopenic' elements exist even in very young populations. These may represent a 'precursor' or forme fruste of the osteosarcopenic obesity phenotype in young healthy overweight/obese subjects, who may progressively develop osteosarcopenia in its full form at an older age. Our study highlights the significance of body composition analysis in medical practice, improving prevention and alleviating later health-related economic burden.

MUS is an index of chronic stress and inflammation and BIA-ACC may provide a useful, bloodless and rapid tool in the clinical setting, distinguishing patients with chronic stress/inflammation from healthy subjects and monitoring their response to treatment.

Recent studies have suggested that body composition is key to health and disease. First, fat tissue is a complex, essential, and highly active metabolic and endocrine organ that responds to afferent signals from traditional hormone systems and the central nervous system but also expresses and secretes factors with important endocrine, metabolic, and immune functions. Second, skeletal muscle mass is an important predictor of health in adult life, while severe mass loss has been associated with the frailty of old age. Studies have shown that skeletal muscle is also an important endocrine organ that secretes factors with autocrine, paracrine, or endocrine actions, which have been associated with inflammatory processes. Third, the bone is also a systemic endocrine regulator playing a pivotal role in health and disease. Finally, proper hydration in humans has been neglected as a health factor, especially in adults. Chronic stress and stress hormone hypersecretion alone or associated with distinct disorders, such as anxiety, depression, obesity, metabolic syndrome, autoimmune disorders, type 2 diabetes mellitus, and polycystic ovary syndrome (PCOS), have been associated with psychological and somatic manifestations, typically, increased fat mass, osteosarcopenia/frailty, cellular dehydration, and chronic systemic inflammation. This review aims to provide new insights into the newly developed concept of stress-related osteosarcopenic obesity and its prevention.

Neonatal intensive care units (NICUs) greatly expand the use of technology. There is a need to accurately diagnose discomfort, pain, and complications, such as sepsis, mainly before they occur. While specific treatments are possible, they are often timeconsuming, invasive, or painful, with detrimental effects for the development of the infant. In the last 40 years, heart rate variability (HRV) has emerged as a noninvasive measurement to monitor newborns and infants, but it still is underused. Hence, the present paper aims to review the utility of HRV in neonatology and the instruments available to assess it, showing how HRV could be an innovative tool in the years to come. When continuously monitored, HRV could help assess the baby's overall wellbeing and neurological development to detect stress-/painrelated behaviors or pathological conditions, such as respiratory distress syndrome and hyperbilirubinemia, to address when to perform procedures to reduce the baby's stress/pain and interventions, such as therapeutic hypothermia, and to avoid severe complications, such as sepsis and necrotizing enterocolitis, thus reducing mortality. Based on literature and previous experiences, the first step to efficiently introduce HRV in the NICUs could consist in a monitoring system that uses photoplethysmography, which is low-cost and non-invasive, and displays one or a few metrics with good clinical utility. However, to fully harness HRV clinical potential and to greatly improve neonatal care, the monitoring systems will have to rely on modern bioinformatics (machine learning and artificial intelligence algorithms), which could easily integrate infant's HRV metrics, vital signs, and especially past history, thus elaborating models capable to efficiently monitor and predict the infant's clinical conditions. For this reason, hospitals and institutions will have to establish tight collaborations between the obstetric, neonatal, and pediatric departments: this way, healthcare would truly improve in every stage of the perinatal period (from conception to the first years of life), since information about patients' health would flow freely among different professionals, and high-quality research could be performed integrating the data recorded in those departments.

The population of older adults, especially those living in the nursing homes, is growing. The sedentary lifestyle and possible poor nutrition in nursing homes place residents (NHRs) at risk for body composition impairments, malnutrition, and, subsequently, numerous chronic diseases. The aim of this study was to assess body composition (including body fluids) and dietary intake in NHRs. The association between osteosarcopenic adiposity syndrome (OSA) and its components, osteopenic adiposity (OA), sarcopenic adiposity (SA), and adiposity-only (AD), and specific macro- and micro-nutrients was evaluated as well. The study included 84 participants (82.1% women), aged 65.3–95.2 years. Body composition was assessed with an advanced bioelectrical impedance device BIA-ACC® and dietary intake was assessed via 24-h recall and analyzed using “Nutrition” software. The majority (95%) of participants were overweight with a high body fat and low muscle and bone mass, leading to a high prevalence of OSA (>50%), OA (13%), and AD (26%). There were only a few participants with SA, and they were not analyzed. The highest extracellular water/total body water ratio was observed in the OSA participants, indicating a heightened inflammatory state. Participants in all three body composition categories had a similar nutrient intake, with protein, fiber, omega-3 fatty acids, and almost all micronutrients being far below recommendations. In conclusion, a high prevalence of OSA among NHRs accompanied by a poor dietary intake, could place these residents at a very high risk for COVID-19 infections. Therefore, optimization of body composition and nutritional status should be included along with standard medical care in order to provide better health maintenance, particularly in the COVID-19 era.

Scarce data exist on the body composition of lean women with polycystic ovary syndrome (PCOS) on treatment with metformin and oral contraceptives (OCs). Thirty-four lean (body mass index 18.5–24.9 kg/m2) women (17 with PCOS on metformin and OCs treatment for six months and 17 controls) aged 18–40 years were assessed for body composition parameters (fat, muscle, glycogen, protein masses, bone masses, and body water compartments) and phase angles. PCOS patients demonstrated lower muscle, glycogen and protein masses (U = 60, p = 0.003), along with a lower bone mineral content and mass (U = 78, p = 0.021; U = 74, p = 0.014) than their healthy counterparts, while total and abdominal fat masses were similar between the two groups. PCOS patients also exhibited increased extracellular body water (U = 10, p < 0.001) and decreased intracellular water, compatible with low-grade inflammation and cellular dehydration. Key differences in body composition between women with PCOS and controls demonstrated an osteosarcopenic body composition phenotype in PCOS patients. A confirmation of these findings in larger studies may render osteosarcopenia management a targeted adjunct therapy in women with PCOS.