OBJECTIVE: Protein-energy wasting (PEW) is a state of metabolic and nutritional derangements in chronic disease states including chronic kidney disease (CKD). Cumulative evidence suggests that PEW, muscle wasting and cachexia are common and strongly associated with mortality in CKD, which is reviewed here.
RESULTS: The malnutrition-inflammation score (KALANTAR Score) is among the comprehensive and outcome-predicting nutritional scoring tools. The association of obesity with poor outcomes is attenuated across more advanced CKD stages and eventually reverses in the form of obesity paradox. Frailty is closely associated with PEW, muscle wasting and cachexia. Muscle loss shows stronger associations with unfavorable outcomes than fat loss. Adequate energy supplementation combined with low-protein diet for the management of CKD may prevent the development of PEW and can improve adherence to low-protein diet, but dietary protein requirement may increase with aging and is higher under dialysis therapy. Phosphorus burden may lead to poor outcomes. The target serum bicarbonate concentration is normal range and at least 23 mEq/l for nondialysis-dependent and dialysis-dependent CKD patients, respectively. A benefit of exercise is suggested but not yet conclusively proven.
CONCLUSIONS: Prevention and treatment of PEW should involve individualized and integrated approaches to modulate identified risk factors and contributing comorbidities.

The Academy of Nutrition and Dietetics (Academy) and the American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) recommend that a standardized set of diagnostic characteristics be used to identify and document adult malnutrition in routine clinical practice. An etiologically based diagnostic nomenclature that incorporates a current understanding of the role of the inflammatory response on malnutrition\'s incidence, progression, and resolution is proposed. Universal use of a single set of diagnostic characteristics will facilitate malnutrition\'s recognition, contribute to more valid estimates of its prevalence and incidence, guide interventions, and influence expected outcomes. This standardized approach will also help to more accurately predict the human and financial burdens and costs associated with malnutrition\'s prevention and treatment and further ensure the provision of high-quality, cost-effective nutrition care.

As a response to metabolic stress, obese critically-ill patients have the same risk of nutritional deficiency as the non-obese and can develop protein-energy malnutrition with accelerated loss of muscle mass. The primary aim of nutritional support in these patients should be to minimize loss of lean mass and accurately evaluate energy expenditure. However, routinely-used formulae can overestimate calorie requirements if the patient\'s actual weight is used. Consequently, the use of adjusted or ideal weight is recommended with these formulae, although indirect calorimetry is the method of choice. Controversy surrounds the question of whether a strict nutritional support criterion, adjusted to the patient\'s requirements, should be applied or whether a certain degree of hyponutrition should be allowed. Current evidence suggested that hypocaloric nutrition can improve results, partly due to a lower rate of infectious complications and better control of hyperglycemia. Therefore, hypocaloric and hyperproteic nutrition, whether enteral or parenteral, should be standard practice in the nutritional support of critically-ill obese patients when not contraindicated. Widely accepted recommendations consist of no more than 60-70% of requirements or administration of 11-14 kcal/kg current body weight/day or 22-25 kcal/kg ideal weight/day, with 2-2.5 g/kg ideal weight/day of proteins. In a broad sense, hypocaloric-hyperprotein regimens can be considered specific to obese critically-ill patients, although the complications related to comorbidities in these patients may require other therapeutic possibilities to be considered, with specific nutrients for hyperglycemia, acute respiratory distress syndrome (ARDS) and sepsis. However, there are no prospective randomized trials with this type of nutrition in this specific population subgroup and the available data are drawn from the general population of critically-ill patients. Consequently, caution should be exercised when interpreting these data.

Sarcopenia and weakness are known to precipitate risk for disability, comorbidity, and diminished independence among aging adults. Resistance exercise has been proposed as a viable intervention to elicit muscular adaptation and improve function. However, the reported prevalence of resistance exercise participation among US adults aged >50 years is very low. This may be largely attributable to inconsistency in study results that fail to fully inform the clinical and public health community of its overall value. Therefore, the purpose of this commentary review is to report the findings of recently published meta-analyses that systematically examined the overall value of resistance exercise among healthy aging adults for strength and lean body mass outcomes. Evidence reveals that not only is resistance exercise very effective for eliciting strength gain and increases in lean body mass, but that there is a dose-response relationship such that volume and intensity are strongly associated with adaptations. These findings reflect and support the viability of progression in resistance exercise dosage to accommodate optimal muscular adaptive response. Progressive resistance exercise should thus be encouraged among healthy adults to minimize degenerative muscular function associated with aging.

In all subgroups of juvenile idiopathic arthritis (JIA), a pathologic loss of bone or the lack of increase in bone mass has been described in a high percentage of cases, even with new therapeutic approaches. The decrease in bone mass is correlated with the duration of active disease and the number of affected joints (cytokines, inactivity). In several studies, muscle mass was the strongest predictor of bone mass. A standardized diagnostic approach to the musculoskeletal system including measures of prophylaxis and therapy therefore seems to be mandatory for all children with JIA who do not achieve rapid remission. In this review, the diagnostic and therapeutic options are described and summarized in an algorithm.