Refeeding improves muscle performance without normalization of muscle mass and oxygen consumption in anorexia nervosa patients

Anorexia nervosa and muscle health: A systematic review of our current understanding and future recommendations for study

OBJECTIVE

Conduct a systematic review on muscle size and strength in individuals with anorexia nervosa (AN).

METHOD

In accordance with PRISMA guidelines, we searched Pubmed for articles published between 1995 and 2022 using a combination of search terms related to AN and muscle size, strength, or metabolism. After two authors screened articles and extracted data, 30 articles met inclusion criteria. Data were coded, and a risk bias was conducted for each study.

RESULTS

The majority of studies focused on muscle size/lean mass (60%, n = 18) and energy expenditure (33%, n = 9), with few studies (17%, n = 5) investigating muscle function or possible mechanisms underlying muscle size (20%, n = 6). Studies supported that individuals with AN have smaller muscle size and reduced energy expenditure relative to controls. In some studies (33%, n = 10) recovery from AN was not sufficient to restore muscle mass or function. Mechanisms underlying short and long-term musculoskeletal alterations have not been thoroughly explored.

DISCUSSION

Muscle mass and strength loss may be an unexplored component of physiological deterioration during and after AN. More research is necessary to understand intramuscular alterations during AN and interventions to facilitate muscle mass and functional gain following weight restoration in AN.

PUBLIC SIGNIFICANCE

Muscle health is important for optimal health and is reduced in individuals with AN. However, we do not understand how muscle is altered at the cellular level throughout the course of AN. Here we review what is currently known regarding muscle health during AN and with weight restoration.

Efficacy and tolerability of a specific blend of amino acids in patients with anorexia nervosa treated in a hospital setting: study protocol for a randomized controlled trial

BACKGROUND

Specific blends of essential amino acids (EAA) containing a high percentage of branched-chain amino acids preserves mitochondrial metabolism and higher physical resistance in elderly mice, increasing their survival and improving physical performance and cognitive functions in malnourished elderly patients. However, no study has been yet done on patients with anorexia nervosa (AN) who regain weight with specialized intensive treatment. The present study aims to evaluate the efficacy of supplementation with EAA on the change in lean body mass (LBM) and other physical and psychological outcomes in patients with AN who are undergoing specialist treatment for eating disorders.

METHODS

This is a 13-week randomized, double-blind, placebo-controlled study. Patients will be randomized to either a mixture of a complex blend of EAA and intermediates of the tricarboxylic acid (TCA) cycle (citrate, malate, succinate) supplementation (or placebo) upon admission at the intensive residential and day-hospital treatment for eating disorders. Ninety-two participants with AN aged 16-50 years will be recruited from a specialized intensive treatment of eating disorders. Double-blind assessment will be conducted at baseline (T0) and the end of the 13 weeks of treatment (T1). The study's primary aim is to evaluate the efficacy of supplementation with EAA and TCA intermediates on the change in lean body mass (LBM) with weight restoration in patients with AN who are undergoing specialist treatment for eating disorders. The secondary aims of the study are to assess the effect of dietary supplementation on physical fitness, weight restoration, modification of AN and general psychopathology, and psychosocial impairment.

DISCUSSION

The study's results will inform researchers and clinicians on whether supplementing a mixture of EAA and TCA cycle intermediates will improve the increase of LBM and other important physical and psychological outcomes in patients with AN who regain weight with specialized intensive treatment.

TRIAL REGISTRATION

NCT, NCT05290285. Registered on 22 March 2022.

Potential bioelectrical impedance analysis (BIA) parameters in prediction muscle strength in women with anorexia nervosa

OBJECTIVES

The role of physical activity in anorexia nervosa (AN) treatment has been investigated. Muscle strength (MS) reflects physical condition and can predict AN patients' response to this novel treatment approach. This study was intended to find bioelectrical impedance analysis (BIA) parameters that predict AN patients' MS.

METHODS

The study included 42 AN patients and 42 healthy ones in the control group. BIA parameters that predict MS were assessed by dividing AN patients into groups by their hand grip strength test score (higher/lower than 22.5 kg).

RESULTS

The highest accuracy for distinguishing AN subjects from the control group was achieved by cell membrane capacitance (AUC = 0.916), impedance at 200 kHz and 5 kHz ratio (AUC = 0.924), phase angle (PA) 5 kHz (AUC = 0.906) and PA 50 kHz (AUC = 0.919). The low MS group had significantly lower values of PA 50 kHz (mean: 4.03 ± 0.80° vs. 4.58 ± 0.65°; p = 0.032) and fat-free mass index (mean: 12.22 ± 1.41 kg/m² vs. 13.14 ± 0.94 kg/m²; p = 0.026). In the univariate model, PA 50 kHz ≥4.037° was associated with the lowest chance of muscle weakness (OR = 0.230; p = 0.005). In the multivariate analysis, PA 50 kHz was the only significant factor of MS (OR = 0.01; p = 0.027).

CONCLUSIONS

PA 50 kHz is the best BIA parameter to predict MS in AN patients. It could be useful for assessment before physical activity treatment application.

Might Starvation-Induced Adaptations in Muscle Mass, Muscle Morphology and Muscle Function Contribute to the Increased Urge for Movement and to Spontaneous Physical Activity in Anorexia Nervosa?

Severely undernourished and underweight anorexia nervosa (AN) patients typically remain active and mobile. Might such persistent physical activity in AN be supported by specific adaptations in muscle tissue during long term undernutrition? To identify potential differences, studies examining the effects of undernutrition on skeletal muscle mass, muscle morphology and muscle function in healthy humans and in AN patients were reviewed. Adjustments in muscle morphology and function in AN did not differ in substance from those in healthy humans, undernourished people, or undergoing semi-starvation. Loss of muscle mass, changes in muscle contractility and atrophy of muscle fibers (predominantly type II fibers) characterized both groups. Muscle innervation was unaffected. Work capacity in men in semi-starvation experiments and in females with AN declined by about 70% and 50%, respectively. Perceptions of fatigue and effort distinguished the groups: signs of general weakness, tiring quickly and avoidance of physical activity that were recorded in semi-starvation were not reported for AN patients. The absence of distinctive starvation-related adjustments in skeletal muscle in AN suggests that new methods, such as muscle gene expression profiles in response to deficient nutrient intake, and better knowledge of the central regulatory circuitries contributing to motor urgency will be required to shed light on the persistent mobility in AN patients.

Echocardiographic Assessment of Ventricular Function During Exercise in Adolescent Female Patients With Anorexia Nervosa

BACKGROUND

Patients with anorexia nervosa (AN) have altered physiologic responses to exercise. The aim of this study was to investigate exercise capacity and ventricular function during exercise in adolescent patients with AN.

METHODS

Sixty-six adolescent female patients with AN and 21 adolescent female control subjects who exercised to volitional fatigue on a semisupine ergometer, using an incremental step protocol of 20 W every 3 min, were retrospectively studied. Heart rate, blood pressure, and echocardiographic Doppler indices were measured at rest and during each stage of exercise. Fractional shortening, rate-corrected mean velocity of circumferential fiber shortening, stress at peak systole, cardiac output, and cardiac index were calculated. Minute ventilation, oxygen consumption, carbon dioxide production, and respiratory exchange ratio were measured using open-circuit spirometry.

RESULTS

Patients with AN had significantly lower body mass index (16.7 vs 19.7 kg/m², P < .001), total work (1,126 vs 1,914 J/kg, P < .001), and test duration (13.8 vs 20.8 min, P < .001) compared with control subjects. Peak minute ventilation, oxygen consumption, and carbon dioxide production were significantly decreased in patients with AN. Heart rate, systolic blood pressure, cardiac index, fractional shortening, and rate-corrected mean velocity of circumferential fiber shortening demonstrated similar patterns of increase with progressive exercise between groups but were decreased at peak exercise in patients with AN. Body mass index percentile, age, peak oxygen consumption, and peak cardiac output were independently associated with exercise duration.

CONCLUSIONS

Adolescent patients with AN have reduced exercise capacity and peak cardiovascular indices compared with control subjects but normal patterns of cardiovascular response during progressive exercise. Systolic ventricular function is maintained during exercise in adolescents with AN.

Therapeutic effects of percutaneous endoscopic gastrostomy on survival in patients with amyotrophic lateral sclerosis: A meta-analysis

Percutaneous endoscopic gastrostomy (PEG) is a method widely used for patients with amyotrophic lateral sclerosis (ALS); nevertheless, its effect on survival remains unclear. The purpose of this meta-analysis study was to determine the effects of PEG on survival in ALS patients. Relevant studies were retrieved from PubMed, EmBase, and the Cochrane Library databases, from inception to June 2017. Studies comparing PEG with other procedures in ALS patients were included. Odds ratios (ORs) in a random-effects model were used to assess the survival at different follow-up periods. Briefly, ten studies involving a total of 996 ALS patients were included. Summary ORs indicated that PEG administration was not associated with 30-day (OR = 1.59; 95%CI 0.93–2.71; P = 0.092), 10-month (OR = 1.25; 95%CI 0.72–2.17; P = 0.436), and 30-month (OR = 1.28; 95% CI 0.77–2.11; P = 0.338) survival rates, while they showed a beneficial effect in 20-month survival rate (OR = 1.97; 95%CI 1.21–3.21; P = 0.007). The survival rate was significantly prominent in reports published before 2005, and in studies with a retrospective design, sample size <100, mean age <60.0 years, and percentage male ≥50.0%. To sum up, these findings suggested that ALS patients administered with PEG had an increased 20-month survival rates, while there was no significant effect in 30-day, 10-month, and 30-month survival rates.

Fast digestive, leucine-rich, soluble milk proteins improve muscle protein anabolism, and mitochondrial function in undernourished old rats

SCOPE

One strategy to manage malnutrition in older patients is to increase protein and energy intake. Here, we evaluate the influence of protein quality during refeeding on improvement in muscle protein and energy metabolism.

METHODS AND RESULTS

Twenty-month-old male rats (n = 40) were fed 50% of their spontaneous intake for 12 weeks to induce malnutrition, then refed ad libitum with a standard diet enriched with casein or soluble milk proteins (22%) for 4 weeks. A 13C-valine was infused to measure muscle protein synthesis and expression of MuRF1, and MAFbx was measured to evaluate muscle proteolysis. mTOR pathway activation and mitochondrial function were assessed in muscle. Malnutrition was associated with a decrease in body weight, fat mass, and lean mass, particularly muscle mass. Malnutrition decreased muscle mTOR pathway activation and protein FSR associated with increased MuRF1 mRNA levels, and decreased mitochondrial function. The refeeding period partially restored fat mass and lean mass. Unlike the casein diet, the soluble milk protein diet improved muscle protein metabolism and mitochondrial function in old malnourished rats.

CONCLUSIONS

These results suggest that providing better-quality proteins during refeeding may improve efficacy of renutrition in malnourished older patients.

Incidence and Risk Factors of Refeeding Syndrome in Head and Neck Cancer Patients-An Observational Study

This study aimed to determine the incidence rates of refeeding phenomena (defined as a decline in p-phosphate) and refeeding syndrome (RFS; defined as development of clinical symptoms in addition to a decline in p-phosphate) in head and neck cancer patients, and to identify risk factors. Fifty-four head and neck cancer patients referred for surgery were included. Forty-six potential risk factors were registered at the baseline, and p-phosphate was measured at Days 2, 4, and 7. Eleven patients (20%) developed RFS, and twenty-eight (52%) developed refeeding phenomena. At baseline, these patients presented a higher prevalence of head and neck pain, eating difficulties, higher p-phosphate levels, lower p-transferrin levels, and, in men, lower b-hemoglobin levels. Patients who developed symptoms had a decline in p-phosphate ≥0.22 mmol/l. At baseline, these patients had higher p-phosphate levels, higher alcohol consumption, and lower p-transferrin and p-sodium levels, as well as a higher prevalence of eating difficulties, low handgrip strength (HGS), and a history of radiation therapy. The risk factors most strongly associated with the development of refeeding phenomena and RFS were pain, eating difficulties, low HGS, high alcohol intake, and previous radiation therapy.

Klotho and the Growth Hormone/Insulin-Like Growth Factor 1 Axis: Novel Insights into Complex Interactions

The growth hormone (GH)/insulin-like growth factor (IGF)-1 axis is pivotal for many metabolic functions, including proper development and growth of bones, skeletal muscles, and adipose tissue. Defects in the axis' activity during childhood result in growth abnormalities, while increased secretion of GH from the pituitary results in acromegaly. In order to keep narrow physiologic concentration, GH and IGF-1 secretion and activity are tightly regulated by hypothalamic, pituitary, endocrine, paracrine, and autocrine factors. Klotho was first discovered as an aging-suppressor gene. Mice that do not express klotho die prematurely with multiple symptoms of aging, several of them are also characteristic of decreased GH/IGF-1 axis activity. Klotho is highly expressed in the brain, the kidney, and parathyroid and pituitary glands, but can also serve as a circulating hormone by its shedding, forming soluble klotho that can be detected in blood, cerebrospinal fluid, and urine. Several lines of evidence suggest an association between klotho levels and activity of the GH/IGF-1 axis: the GH-secreting cells in the anterior pituitary of klotho-deficient mice are hypotrophic; klotho levels are altered in subjects with pathologies of the GH/IGF-1 axis; and accumulating data indicate that klotho is a direct regulator of GH secretion. Thus, klotho seems to be a new player in the intricate regulation of the GH/IGF-1 axis.

Alteration in serum klotho levels in anorexia nervosa patients

BACKGROUND & AIMS

Klotho is a trans-membrane protein which can be shed to act as a hormone; its blood levels may be regulated by the GH/IGF-1 axis. Klotho deficient mice exhibit short lifespan and characteristics of aging and malnutrition, including decreased fat and muscle mass, osteopenia, and impaired fertility. As anorexia nervosa (AN) is characterized by malnutrition and GH resistance, we hypothesized klotho levels would be altered in AN, and aimed to assess klotho levels in undernourished AN patients and changes in klotho following weight rehabilitation.

PARTICIPANTS AND METHODS

19 adolescent female AN inpatients (aged 16.1 ± 1.8 years) admitted to an inpatient service for eating disorders in a tertiary center were recruited. Blood samples were obtained on admission and after weight restoration (interval 4.0 ± 2.3 months) and analyzed for klotho, IGF-1, calcium, phosphorus, and alkaline phosphatase.

RESULTS

Klotho levels on admission were lower than expected for age, and correlated with lumbar spine BMD Z-score (r = -0.81, p < 0.001) and alkaline phosphatase levels (r = 0.66, p = 0.003) but not with age, height-SDS, weight-SDS, BMI-SDS, or serum calcium, phosphorus and IGF-1 levels. Both IGF-1 and klotho levels increased significantly during hospitalization (IGF-1: 44 ± 17 nmol/l to 53 ± 11 nmol/l, p = 0.008; klotho: 1061 ± 421 pg/ml to 1519 ± 781 pg/ml, p = 0.008).

CONCLUSIONS

Klotho levels are low in the acute stage of AN and increase with nutritional rehabilitation. Low klotho on admission may be secondary to low IGF-1 levels and may contribute to the clinical manifestations of AN. The role of klotho in the pathophysiology of AN and as a novel marker of disease severity should be further explored.

Eating disorders, physical fitness and sport performance: a systematic review

Background: Eating disorders are health problems that are particularly prevalent in adolescents and young adults. They are associated with considerable physical health and psychosocial morbidity, and increased risk of mortality. We set out to conduct a systematic review to determine their effect on physical fitness in the general population and on sport performance in athletes. Methods/Design: A systematic review of the relevant peer-reviewed literature was performed. For inclusion, articles retrieved from PubMed had to be published in English between 1977 and 2013. Wherever possible, methods and reporting adhere to the guidelines outlined in the PRISMA statement. Some additional studies were retrieved from among those cited in the reference lists of included studies and from non-electronic databases. Literature searches, study selection, method and quality appraisal were performed independently by two authors, and data was synthesized using a narrative approach. Results: Of the 1183 articles retrieved, twenty-nine studies met the inclusion criteria and were consequently analysed. The available data indicate that eating disorders have a negative effect on physical fitness and sport performance by causing low energy availability, excessive loss of fat and lean mass, dehydration, and electrolyte disturbance. Discussion: Although the paucity of the available data mean that findings to date should be interpreted with caution, the information collated in this review has several practical implications. First, eating disorders have a negative effect on both physical fitness and sport performance. Second athletics coaches should be targeted for education about the risk factors of eating disorders, as deterioration in sport performance in athletes, particularly if they are underweight or show other signs of an eating disorder, may indicate the need for medical intervention. However, future studies are needed, especially to assess the direct effect of eating disorders on sport performance.

Effect of nutritional support on mitochondrial complex I activity in malnourished patients with anorexia nervosa

Previous studies have shown a reduction in lymphocyte mitochondrial complex I activity (CIA) in malnourished patients, which is restored after refeeding. Our aim was to evaluate the usefulness of CIA as an indicator of nutritional status in anorexia nervosa patients. Twelve malnourished anorexia nervosa females (mean age, 24.5 years) were admitted to the Eating Disorders Unit. Basal and weekly anthropometrics, bioelectric impedance (BIA), body composition, and CIA were performed until discharge. Patients were matched to 25 healthy females and refeeding was adjusted according to the Unit’s protocol. Statistics were used as appropriated and significance was reached at p < 0.05. Patients showed a significant reduction in body mass index, fat mass and fat free mass (FFM), triceps skinfold, and waist circumference on admission as compared with the control group. Parameters improved during hospitalization, but they failed to reach normal values at discharge. Compared with controls, CIA was significantly lower in patients on admission (2.16 vs. 5.68 nmol·min−1·mg protein−1). Refeeding and weight gain did not restore CIA. A positive association (r2= 0.69) was found between FFM and CIA in patients at discharge. Malnourished females with anorexia nervosa have lower CIA than controls that is not recovered after refeeding. This could be because of a low FFM exacerbated by physical inactivity while in hospital.

Evidence-based risk assessment and recommendations for physical activity clearance: cognitive and psychological conditions

Physical activity has established mental and physical health benefits, but related adverse events have not received attention. The purpose of this paper was to review the documented adverse events occurring from physical activity participation among individuals with psychological or cognitive conditions. Literature was identified through electronic database (e.g., MEDLINE, psychINFO) searching. Studies were eligible if they described a published paper examining the effect of changes on physical activity behaviour, included a diagnosed population with a cognitive or psychological disorder, and reported on the presence or absence of adverse events. Quality of included studies was assessed, and the analyses examined the overall evidence by available subcategories. Forty trials passed the eligibility criteria; these were grouped (not mutually exclusively) by dementia (n = 5), depression (n = 10), anxiety disorders (n = 12), eating disorders (n = 4), psychotic disorders (n = 4), and intellectual disability (n = 15). All studies displayed a possible risk of bias, ranging from moderate to high. The results showed a relatively low prevalence of adverse events. Populations with dementia, psychological disorders, or intellectual disability do not report considerable or consequential adverse events from physical activity independent of associated comorbidities. The one exception to these findings may be Down syndrome populations with atlantoaxial instability; in these cases, additional caution may be required during screening for physical activity. This review, however, highlights the relative paucity of the reported presence or absence of adverse events, and finds that many studies are at high risk of bias toward reporting naturally occurring adverse events.

Current status of the diagnosis and management of amyotrophic lateral sclerosis in Korea: a multi-center cross-sectional study

Background and Purpose

Recently published, evidence-based guidelines should alter the management of amyotrophic lateral sclerosis (ALS)/motor neuron disease (MND). However, the newest recommendations for ALS/MND therapy are not reflected in actual clinical practice. We sought to evaluate the current status of the diagnosis and management of ALS in Korea.

Methods

The Korean ALS/MND research group was organized in 2010, involving more than 50 neurologists from neuromuscular centers in Korea. Participating centers collected data from April to September 2010 on the diagnosis and management of patients with ALS. Data forms from the ALS patient care database, which is a component of the ALS clinical assessment, research, and education program (http://www.outcomes-umassmed.org/ALS/), were modified and used for data collection.

Results

In total, 373 sporadic ALS cases from 35 centers were enrolled. The demographic features and clinical findings were similar to those in previous reports from other countries. The mean age at onset was 50-60 years, and a slight male predominance was observed. The enrolled patients predominantly showed focal onset of cervical or lumbosacral symptoms. Only about one-half of the indicated patients (31.4%) received a physician's recommendation for a parenteral gastrostomy, and 18.1% underwent the procedure. Noninvasive ventilation was recommended in 23% of patients, but applied in only 9.5% of them. Tracheostomy was performed in 12.7% of patients.

Conclusions

The demographic and clinical features of the diagnosis and management of ALS in Korea are similar to those reported in other countries; however, supportive management, as recommended in evidence-based guidelines, are not yet widely recommended or performed for patients with ALS in Korea.

Respiratory functions in adolescents hospitalized for anorexia nervosa: a prospective study

OBJECTIVE

To examine the effects of malnourishment on the respiratory system of adolescents with anorexia nervosa (AN) hospitalized for medical stabilization.

METHOD

Prospective study.

STUDY GROUP

hospitalized adolescents with recent onset (<1 year) AN.

CONTROL GROUP

adolescents hospitalized for other diagnoses. Excluded: participants with lung disease.

RESULTS

Patients' characteristics (mean ± SD) for the AN (n = 16) and the control group (n = 13) on admission were: age: 15.0 ± 1.7 vs. 15.2 ± 1.4 years, p = 0.7; body mass index (BMI): 15.5 ± 2.3 vs. 19.8 ± 2.9 kg/m², p < 0.001; venous pH 7.34 ± 0.02 vs. 7.38 ± 0.03, p < 0.001; PCO₂ 53.3 ± 4.1 vs. 42.5 ± 3.1 mm Hg, p < 0.001; and HCO₃ 28.7 ± 2.0 vs. 25.3 ± 2.4 meq/L, p < 0.001, respectively. There were no significant differences in nocturnal respiratory rates, pulse-oximetry oxygen saturations, or end-tidal CO₂. Pulmonary function tests (PFTs) in adolescents with AN revealed no obstructive, restrictive, or significant pulmonary vascular disease except for lower peak expiratory flow rates (PEFRs). During hospitalization (12.3 ± 3.8 days), their weight, BMI, mean nocturnal heart rate, and respiratory rate increased significantly, while their venous PCO₂ and HCO₃ decreased significantly without significant changes in PFTs.

DISCUSSION

Adolescents with recent onset AN, admitted for medical stabilization, demonstrate hypercapnia despite normal PFTs, except for decreased PEFRs. These could result from decreased respiratory muscle strength and/or abnormal control of breathing.

Changes in physical fitness, bone mineral density and body composition during inpatient treatment of underweight and normal weight females with longstanding eating disorders

The purpose of this study was to examine changes in aerobic fitness, muscular strength, bone mineral density (BMD) and body composition during inpatient treatment of underweight and normal weight patients with longstanding eating disorders (ED). Twenty-nine underweight (BMI < 18.5, n = 7) and normal weight (BMI ≥ 18.5, n = 22) inpatients (mean (SD) age: 31.0 (9.0) years, ED duration: 14.9 (8.8) years, duration of treatment: 16.6 (5.5) weeks) completed this prospective naturalistic study. The treatment consisted of nutritional counseling, and 2 × 60 min weekly moderate intensive physical activity in addition to psychotherapy and milieu therapy. Underweight patients aimed to increase body weight with 0.5 kg/week until the weight gain goal was reached. Aerobic fitness, muscular strength, BMD and body composition were measured at admission and discharge. Results showed an increase in mean muscular strength, total body mass, fat mass, and body fat percentage, but not aerobic capacity, among both underweight and normal weight patients. Lumbar spine BMD increased among the underweight patients, no changes were observed in BMD among the normal weight patients. Three out of seven underweight patients were still underweight at discharge, and only three out of nine patients with excessive body fat (i.e., >33%) managed to reduce body fat to normal values during treatment. These results calls for a more individualized treatment approach to achieve a more optimal body composition among both underweight and normal to overweight patients with longstanding ED.

Respiratory acidosis in adolescents with anorexia nervosa hospitalized for medical stabilization: a retrospective study

OBJECTIVE

To examine the effect of malnutrition due to anorexia nervosa (AN) on venous blood gases of adolescents with AN hospitalized for medical stabilization.

METHOD

This retrospective study included 45 adolescents with recent onset (<1 year) AN diagnosed by DSM-IV criteria and excluded subjects with a history of lung disease.

RESULTS

Mean (± SD) age at hospitalization was 15.0 ± 2.0 years; time from onset of symptoms was 6.8 ± 3.0 months; body mass index (BMI) was 15.2 ± 1.5 kg/m(2) ; and minimal nocturnal heart rate (MNHR) was 39.8 ± 7.2 beats/min. On admission, pH was 7.32 ± 0.02, pCO(2) was 53.8 ± 4.6 mm Hg, and HCO(3) was 28.1 ± 2.1 mEq/l. Significant changes (p < .001) occurred during the relatively short hospitalization (9.7 ± 5.1 days): venous pH increased, pCO(2) decreased, HCO(3) decreased, MNHR increased, and heart rate orthostasis decreased. Mild respiratory acidosis (pH < 7.35 and pCO(2) > 45 mm Hg) was observed in 78% of the patients on admission and only in 35% at discharge (p = .0003). Positive correlations were found between % of weight loss and pCO(2) on admission and between BMI on admission and the delta pCO(2) during hospitalization.

DISCUSSION

Mild respiratory acidosis is common in adolescents with recently diagnosed AN, hospitalized for medical stabilization. Respiratory acidosis improves with bed rest and refeeding. The clinical significance of these findings should be further evaluated.

Nocturnal enuresis in adolescents with anorexia nervosa: prevalence, potential causes, and pathophysiology

OBJECTIVE

The aim of this study was to determine the prevalence and potential causes of secondary nocturnal enuresis (NE) in adolescents with anorexia nervosa (AN).

METHOD

Adolescents with AN completed the Incontinence Symptom Index-Pediatric (ISI-P), a self-report urinary incontinence survey. Those who had NE associated with the onset of AN on the ISI-P completed a comprehensive clinical and laboratory evaluation, including urinary flow measurements.

RESULTS

The prevalence of NE in adolescents with AN was 17.0% (10 of 59). The overall frequency of day- and night-time urinary incontinence symptoms in adolescents with AN was 62.7%; urgency incontinence, 57.6%; stress incontinence, 32.2%; and insensate incontinence, 17.0%. Nine of the 10 adolescents with NE had secondary NE and confirmed that bedwetting ceased after weight restoration.

DISCUSSION

Decreased functional bladder capacity and detrusor instability may contribute to the NE observed in this population. The high prevalence of NE in adolescents with AN warrants further study to determine the potential causative pathways. Clinicians who work with adolescents with AN should assess for this problem.

Hand grip strength: outcome predictor and marker of nutritional status

BACKGROUND & AIMS

Among all muscle function tests, measurement of hand grip strength has gained attention as a simple, non-invasive marker of muscle strength of upper extremities, well suitable for clinical use. This review outlines the prognostic relevance of grip strength in various clinical and epidemiologic settings and investigates its suitability as marker of nutritional status in cross-sectional as well as intervention studies.

METHODS

Studies investigating grip strength as prognostic marker or nutritional parameter in cross-sectional or intervention studies were summarized.

RESULTS AND CONCLUSIONS

Numerous clinical and epidemiological studies have shown the predictive potential of hand grip strength regarding short and long-term mortality and morbidity. In patients, impaired grip strength is an indicator of increased postoperative complications, increased length of hospitalization, higher rehospitalisation rate and decreased physical status. In elderly in particular, loss of grip strength implies loss of independence. Epidemiological studies have moreover demonstrated that low grip strength in healthy adults predicts increased risk of functional limitations and disability in higher age as well as all-cause mortality. As muscle function reacts early to nutritional deprivation, hand grip strength has also become a popular marker of nutritional status and is increasingly being employed as outcome variable in nutritional intervention studies.

Changes in nutritional status and dietary intake during and after head and neck cancer treatment

BACKGROUND

The purpose of this study was to test whether nutritional status of patients with head and neck cancer changes during and after treatment.

METHODS

Nutritional status (including body weight, lean mass, and fat mass) and dietary intake were assessed in 29 patients with head and neck cancer. Patients were assessed 1 week before, and 1 and 4 months after treatment (radiotherapy, either alone or combined with chemotherapy or surgery).

RESULTS

During treatment, body weight (-3.6 ± 5.3 kg; p = .019) and lean mass (-2.43 ± 2.81 kg; p = .001) significantly declined. Patients with sufficient intake (≥35 kcal and ≥1.5 grams protein/kg body weight) lost less body weight and lean mass than patients with insufficient intake (mean difference, -4.0 ± 1.9 kg; p = 0.048 and -2.1 ± 1.0 kg; p = .054, respectively). After treatment, only patients with sufficient intake gained body weight (2.3 ± 2.3 kg) and lean mass (1.2 ± 1.3 kg).

CONCLUSION

Patients with head and neck cancer fail to maintain or improve nutritional status during treatment, despite sufficient intake.

A randomized trial on the efficacy of a 2-month tube feeding regimen in anorexia nervosa: A 1-year follow-up study

BACKGROUND & AIMS

Despite the high mortality rate in malnourished anorexia nervosa (AN) patients, very few trials have prospectively studied the efficacy of tube feeding.

METHODS

This open prospective study was conducted in malnourished AN patients, who were randomized in tube feeding (n=41) or control (n=40) groups during a 2-month period. Thereafter, body weight, body mass gain, energy intake, eating behavior and relapse rates were compared during a 1-year follow-up, using paired Student t-test and ANOVA.

RESULTS

At the end of the 2-months period, weight gain was 39% higher in the tube feeding group than in the control group (194+/-14 vs 126+/-19g/day; P<0.01). The fat-free mass gain was greater in the tube-feeding group: 109+/-14 vs 61+/-17g/day (P<0.01). Energy intake was higher in the tube feeding group than in the control group (P<0.05), as well as the decrease in bingeing episodes (P<0.01). Most patients thought that CEN improved their eating disorder. After discharge, the relapse-free period was longer in the CEN group than in the control one: 34.3+/-8.2 weeks vs 26.8+/-7.5 weeks (P<0.05).

CONCLUSION

CEN is helpful in malnourished AN patients for weight restoration, without hindrance on the eating behavior therapy nor inducing a more rapid relapse.

Hormonal and psychological factors linked to the increased thermic effect of food in malnourished fasting anorexia nervosa

OBJECTIVES

In patients with anorexia nervosa (AN), weight gain is lower than that expected from the energy content of the meals. Thus we investigated the thermic effect of food (TEF) in relation to subjective feelings and plasma hormone levels in a group of AN patients.

METHODS

TEF, feelings (14 items), and plasma release of beta-endorphin, ACTH, cortisol, dopamine, and catecholamines were evaluated in 15 AN patients (body mass index, 13.6 +/- 1.2 kg.m(-2)) and in 15 healthy women after three gastric loads (0, 300, 700 kcal) infused by a nasogastric tube in a blind design.

RESULTS

In AN, the blind loads induced an energy-dependent increase in TEF (P < 0.001), which was higher than that observed in healthy women (P < 0.001). Only in AN, a load-dependent decline in the high basal plasma level of beta-endorphin (P < 0.01), an increase in plasma ACTH (P < 0.02) after the two caloric loads, and an increase in cortisol, norepinephrine, and dopamine levels after the 700-kcal load only (P < 0.05) were noted. A calorie-dependent (P < 0.001) increase in nausea, abdominal discomfort, and fear of being fat ratings and a decrease in liking to eat (P < 0.001) and body image were observed in AN patients (P < 0.05). TEF correlated with ratings on satiation, nausea, uncomfortable abdominal swelling, body image, and fear of being fat (for all, P < 0.01).

CONCLUSION

In AN women, blindly infused loads induced a dose-dependent increase in TEF, which correlated with the increase in plasma cortisol, ACTH, and catecholamines as in unpleasant sensations, fear of being fat, and anxiety as well as a decline in elevated basal beta-endorphin. These results could explain the difficulty for AN patients in gaining weight.

Double-blind, placebo-controlled, randomized study of eicosapentaenoic acid diester in patients with cancer cachexia

PURPOSE

Eicosapentaenoic acid (EPA) has been proposed to have specific anticachectic effects. This trial compared EPA diethyl ester with placebo in cachectic cancer patients for effects on weight and lean body mass.

PATIENTS AND METHODS

Five hundred eighteen weight-losing patients with advanced gastrointestinal or lung cancer were studied in a multicenter, double-blind, placebo controlled trial. Patients were randomly assigned to receive a novel preparation of pure EPA at a dose of 2 g or 4 g daily or placebo (2g EPA, n = 175; 4 g EPA, n = 172; placebo, n = 171). Patients were assessed at 4 weeks and 8 weeks.

RESULTS

The groups were well balanced at baseline. Mean weight loss at baseline was 18% (n = 518). Over the 8-week treatment period, both intention-to-treat analysis and per protocol analysis revealed no statistically significant improvements in survival, weight, or other nutritional variables. There was, however, a trend in favor of EPA with analysis of the primary end point, weight, at 8 weeks showing a borderline, nonsignificant treatment effect (P = .066). Relative to placebo, mean weight increased by 1.2 kg with 2 g EPA (95% CI, 0 kg to 2.3 kg) and by 0.3 kg with 4 g EPA (-0.9 kg to 1.5 kg).

CONCLUSION

The results indicate no statistically significant benefit from single agent EPA in the treatment of cancer cachexia. Future studies should concentrate on other agents or combination regimens.

Chronotropic incompetence to exercise separates low body weight from established anorexia nervosa

Chronotropic incompetence (CI), characterized by an attenuated heart rate (HR) response to exercise could participate to the limitation of exercise capacity in anorexia nervosa (AN). Therefore, we evaluated the role of cardiac sympathetic responsiveness in AN patients. In addition, the ambulatory value of autonomic control using spectral analysis of heart rate variability (HRV) was determined and correlated to maximal exercise performance. Twenty-two patients hospitalized for weight loss and suspicion of AN were included in the study. All performed a symptom-limited exercise test with measurement of gas exchange for chronotropic response to exercise evaluation. Holter ECG recordings allowed daytime and night-time spectral domain HRV analysis in order to evaluate the alteration of sympathetic control of HR in free-living conditions. CI defined as a failure to achieve 80% of heart rate reserve (%HRR) was observed in 13 (59%) patients (CI+). This group presented a higher body mass deficit than the group without CI (CI-; -35.1 +/- 8.7% versus -26.1 +/- 10.7%; P<0.05). Obviously, patients with a lower body mass index (BMI < 16 kg m(-2), n = 14) revealed a more severe limitation to maximal exercise with a lower peak HR, a lower peak Vo(2), and a lower maximal O(2) pulse (P<0.05). BMI was significantly correlated to peak Vo(2), maximal HR, and %HRR achieved at peak exercise. Daytime HRV parameters reflecting the sympathetic autonomic equilibrium (LF nu, LF/HF ratio) were significantly lower in CI+ patients. Blunted sympathetic response to maximal exercise is frequent and correlated to weight deficit. The present data suggest a major autonomic derangement in AN characterized by a cardiac sympathetic withdrawal.

Effect of feeding malnourished patients for 1 mo on mitochondrial complex I activity and nutritional assessment measurements

BACKGROUND

We showed previously that the activity of complex I (the first enzyme of the electron transport chain) in peripheral blood mononuclear cells decreases with malnutrition and increases to a subnormal value after 1 wk of refeeding, but the traditional markers of nutritional status do not do so.

OBJECTIVE

The aim of this study was to ascertain whether a period of nutritional intervention longer than 1 wk would normalize complex I activity and traditional markers of nutritional status.

DESIGN

Fifteen malnourished patients (7 women and 8 men) with > or =10% body weight loss over the previous 6 mo were studied on the day of their admission to hospital and 7, 14 and 30 d after the beginning of nutritional support. Complex I activity in peripheral blood mononuclear cells, weight, height, body composition, body water compartments, dietary intake, and serum albumin concentrations were measured on each occasion. The results before and during nutritional intervention were compared with values obtained in 30 healthy volunteers (17 women and 13 men).

RESULTS

Complex I activity increased significantly after the first week of refeeding (P < 0.001) and reached a normal value after 1 mo of nutritional supplementation. Among the classic markers of nutritional status, only the ratio of extracellular water to intracellular water tended to decrease over the refeeding period.

CONCLUSION

Complex I activity increases rapidly and is normalized by refeeding at a time when other markers of nutritional status do not change significantly.

Longitudinal and cross-sectional effects of C-reactive protein, equilibrated normalized protein catabolic rate, and serum bicarbonate on creatinine and albumin levels in dialysis patients

BACKGROUND

Loss of muscle mass and hypoalbuminemia each may result in part from either malnutrition, inflammation, or a combination of both. Short-term acidosis increases muscle protein catabolism and inhibits albumin synthesis.

METHODS

We analyzed albumin and creatinine levels as outcome variables and their association with C-reactive protein (CRP) level, equilibrated normalized protein catabolic rate (enPCR), and serum bicarbonate level as independent variables from laboratory data obtained from patients in the Hemodialysis Study. Analyses controlled for race, sex, age, body mass index, and randomized treatment group.

RESULTS

Albumin level correlated with both enPCR and CRP level, but not serum bicarbonate level, in both cross-sectional and longitudinal analyses. Effects of CRP level and enPCR were not linear. Albumin level correlated positively with enPCR for an enPCR less than 1.0 g/kg/d, but not for a greater enPCR, and correlated inversely with CRP level for a CRP level greater than 13 mg/L. Similarly, creatinine level correlated with both enPCR and CRP level. As in the case of albumin level, effects were not linear. Creatinine level correlated positively with enPCR for values less than 1.0 g/kg/d, but not for greater enPCR values. In contrast to albumin level, creatinine level correlated negatively with serum bicarbonate level, even when adjusted for enPCR.

CONCLUSION

Albumin and creatinine levels are independently associated with nutrition (enPCR) and inflammation (CRP level). The cross-sectional relationship with enPCR is apparent only at values less than 1.0 g/kg/d. CRP level is associated with reduced albumin and creatinine values when increased to values greater than 5.6 mg/dL. CRP may be increased to levels associated with increased cardiovascular risk with little or no effect on either serum albumin or creatinine level. Thus, a normal albumin level does not exclude elevated CRP levels.

Veränderung der Muskelkraft bei Patientinnen mit Anorexia nervosa während der stationären Behandlung - eine Pilotstudie

Zusammenfassung: Fragestellung: Die Veränderung der Muskelkraft bei Patientinnen mit Anorexia nervosa während der stationären Behandlung sollte durch exakte Messung bestimmt werden. Methode: Unter Verwendung einer etablierten Messvorrichtung inkl. des Softwareprogramms «Quantitative Muscle Assessment» wurden in den Wochen 1, 2, 3, 4, 6, 8 und 10 des stationären Aufenthaltes die Maximalkräfte in vier verschiedenen Übungen für jede Körperseite bei zehn Patientinnen bestimmt. Alle wiesen vor der stationären Aufnahme einen vergleichbaren Krankheitsverlauf mit reiner Nahrungsrestriktion ohne überdurchschnittliche sportliche Betätigung auf. Ergebnisse: Es ergaben sich Hinweise auf einen interindividuell zu beobachtenden mehrphasigen Verlauf der Kraftrestitution. Die aufgrund der einfachen Durchführung andernorts häufig angewandte Übung Handgrip zeigte im Gegensatz zu den anderen untersuchten Muskelgruppen keine einheitliche Entwicklung. Seitendifferenzen waren nicht zu beobachten. Schlussfolgerungen: Patientinnen mit Anorexia nervosa zeigen eine objektivierbare, interindividuell vergleichbare, mehrphasige Zunahme der Maximalkraft der untersuchten Muskelgruppen während der Gewichtsrestitution.

Effect of malnutrition and short-term refeeding on peripheral blood mononuclear cell mitochondrial complex I activity in humans

BACKGROUND

Previous investigations in rats have shown that the first enzyme of the mitochondrial electron transport chain (complex I) is altered in peripheral blood mononuclear cells (PBMCs) and muscle by dietary manipulations.

OBJECTIVE

We hypothesized that similar changes would occur in human PBMCs as a result of dietary malnutrition and short-term refeeding irrespective of the presence or absence of active inflammatory bowel disease (IBD).

DESIGN

Fourteen malnourished patients with active IBD, 13 malnourished patients without IBD, and 42 healthy subjects were investigated. Complex I activity, body mass index, body composition, energy and protein intakes, and resting energy expenditure were measured. Five patients without IBD and 6 patients with IBD were investigated after 7 d of refeeding.

RESULTS

In patients without IBD, weight loss was mainly due to a loss of fat mass. In contrast, weight loss in IBD patients was due to a loss of both fat-free mass and fat mass. Complex I activity was reduced to the same degree in both groups of patients and was significantly lower than that observed in healthy subjects. In both groups of patients, complex I activity correlated significantly with body weight, body mass index, percentage weight loss, and fat mass. Complex I activity increased significantly after 1 wk of refeeding in both groups of patients before observed changes of measured nutritional assessment indexes.

CONCLUSION

Our study showed that mitochondrial complex I activity measured in PBMCs seems to be a specific marker of dietary malnutrition and responds rapidly to refeeding.

Respiratory muscle weakness and anorexia nervosa

BACKGROUND

Nutritional recovery in anorexia nervosa (AN) is associated with improved exercise tolerance.

METHOD

We describe the investigation of a male with AN. Despite nutritional recovery, he complained of impaired exercise tolerance.

RESULTS

Respiratory muscle weakness was demonstrated as the cause of the impaired exercise tolerance.

DISCUSSION

Weakness of the muscles of respiration results from prolonged malnutrition. The diaphragmatic muscle may be slower to recover than other muscles. This can cause impaired exercise tolerance due to shortness of breath on exertion, despite nutritional recovery.

Muscle strength as a predictor of loss of functional status in hospitalized patients

OBJECTIVE

The incidence of protein-calorie malnutrition in hospitalized adult patients can reach 30% to 50% and adversely affect clinical outcome. We evaluated the efficacy of muscle strength to predict functional derangement and detect early changes in nutrition status in hospitalized patients.

METHODS

Patients hospitalized at medical and surgical wards from two different hospitals in Santiago, Chile, were studied during their hospital stay. Subjective Global Assessment of nutrition status and laboratory parameters were measured on admission. Anthropometric measures, handgrip dynamometry, and maximal inspiratory and expiratory pressures were measured on admission and discharge. The Karnofsky index was used to assess functional status. Twice weekly, caloric balance was calculated with indirect calorimetry and assessment of dietary intake.

RESULTS

From the initial selection of patients (n = 70), 50 patients (26 men and 24 women) completed the study. Median hospital stay was 10 d. Subjective Global Assessment was associated with anthropometric data, handgrip dynamometry, and serum levels of total proteins. Patients in whom functional status declined during hospital stay, on admission had lower left handgrip strength, a worse Subjective Global Assessment classification, were older, and had lower fat mass. No association between caloric balance during hospital stay and changes in muscle strength was observed.

CONCLUSIONS

Subjective Global Assessment, handgrip strength, and fat mass were good predictors for the decline in functional status during hospital stay. No association between caloric balance and changes in muscle strength was observed.

Nitrogen Metabolism and Bone Metabolism Markers in Healthy Adults during 16 Weeks of Bed Rest

Background: The associations between nitrogen metabolism and bone turnover during bed rest are still not completely understood.

Methods: We measured nitrogen balance (nitrogen intake minus urinary nitrogen excretion) and biochemical metabolic markers of calcium and bone turnover in six males before head-down tilt bed rest (baseline), during 2, 10, and 14 weeks of immobilization, and after reambulation.

Results: The changes in nitrogen balance were highest between baseline and week 2 (net change, −5.05 ± 1.30 g/day; 3.6 ± 0.6 g/day at baseline vs −1.45 ± 1.3 g/day at week 2; P&lt;0.05). In parallel, serum intact osteocalcin (a marker of bone formation) was already reduced and renal calcium and phosphorus excretions were increased at week 2 (P &lt;0.05). Fasting serum calcium and phosphorus values and renal excretion of N-telopeptide (a bone resorption marker) were enhanced at weeks 10 and 14 (P &lt;0.05–0.001), whereas serum concentrations of parathyroid hormone, calcitriol, and type I collagen propeptide (a marker of bone collagen formation) were decreased at week 14 (P &lt;0.05–0.01). Significant associations were present between changes of serum intact osteocalcin and 24-h calcium excretion (P &lt;0.001), nitrogen balance and 24-h phosphorus excretion (P &lt;0.001), nitrogen balance and renal N-telopeptide excretion (P &lt;0.05), and between serum osteocalcin and nitrogen balance (P &lt;0.025).

Conclusions: Bone formation decreases rapidly during immobilization in parallel with a higher renal excretion of intestinally absorbed calcium. These changes appear in association with the onset of a negative nitrogen balance, but decreased bone collagen synthesis and enhanced collagen breakdown occur after a time lag of several weeks.

Ageing and muscle: the effects of malnutrition, re-nutrition, and physical exercise

Because of the metabolic changes caused by ageing, malnutrition is accompanied by a preferential loss of fat-free mass in the elderly, and it exaggerates the physiological loss of body cell mass, muscle mass and muscle function observed in the aged. Exercise training has positive anabolic effects even in the frail elderly, and may improve the effect of re-nutrition in malnourished elderly patients.

Effect of hypoenergetic feeding and refeeding on muscle and mononuclear cell activities of mitochondrial complexes I--IV in enterally fed rats

BACKGROUND

Previous studies suggested that cell energetics are altered by malnutrition.

OBJECTIVE

We hypothesized that nutritional manipulations influence mitochondrial enzyme activities of the electron transport chain in both skeletal muscle and blood mononuclear cells.

DESIGN

After a gastrostomy tube was inserted, 44 rats were randomly assigned to 1 of 4 experimental groups: control fed (CF; 364 kJ/d for 7 d), hypoenergetic fed (HF; 92 kJ/d for 7 d), hypoenergetic protein refed (HPR; 92 kJ/d for 7 d and then 129 kJ/d for 1 d), and hypoenergetic glucose refed (HGR; 92 kJ/d for 7 d and then 129 kJ/d for 1 d). The protein and glucose contents of the liquid formulas were different for the HPR and HGR groups. After mitochondria were isolated from the soleus muscle, the activities of complexes I--IV were measured spectrophotometrically. Because of the lack of available tissue, only the activity of complex I was measured in the mononuclear cell extract.

RESULTS

The recovery of complex activities in the CF and HF groups was not significantly different in the mitochondrial fraction of the soleus muscle. Compared with that in the CF group, the activities of complexes I--III in the mitochondrial fraction of the soleus muscle and the activity of complex I in mononuclear cells were significantly lower in the HF group. The activities of complexes I--III in the mitochondrial fraction of the soleus muscle and the activity of complex I in mononuclear cells were significantly higher in the HPR than in the HF group. The activity of complex IV was generally not affected by nutritional manipulations.

CONCLUSION

Malnutrition decreases activities of mitochondrial complexes, which are restored by protein but not glucose refeeding.

Functional and metabolic early changes in calf muscle occurring during nutritional repletion in malnourished elderly patients

BACKGROUND

Metabolic alterations in skeletal muscle associated with malnutrition and the potential reversibility of such alterations during refeeding are not fully understood.

OBJECTIVE

We characterized early changes in muscle during refeeding in malnourished, hospitalized elderly subjects.

DESIGN

Muscle function, metabolism, and mass were evaluated in 24 clinically stable patients (11 were malnourished) by using isokinetic plantar flexor torque measurements and nuclear magnetic resonance (NMR) imaging for medial gastrocnemius mass assessment and 31P and 13C NMR spectroscopy for inorganic phosphate (Pi), phosphocreatine, and glycogen quantitation.

RESULTS

Malnourished subjects had lower muscle mass (P < 0.02) and tended to have lower strength than did control subjects. In malnourished subjects, muscle strength increased after refeeding (P < 0.01) whereas muscle mass was unchanged. The ratio of Pi to ATP was lower in malnourished than in control subjects (P < 0.001) and increased during refeeding (P < 0.01). The mean ratio of phosphocreatine to ATP was lower in malnourished than in control subjects (P < 0.01) and increased to control values after refeeding. Muscle glycogen showed a scattered distribution for malnourished subjects; the mean value did not differ significantly from that of control subjects, either at baseline or after refeeding.

CONCLUSIONS

The lower ratio of phosphocreatine to ATP in malnourished subjects could have resulted from either lower total muscle creatine or reduced oxidative capacities. High or normal glycogen associated with a low Pi-to-ATP ratio in malnourished subjects suggested preferential use of lipid over carbohydrate for energy supply, which is known to reduce muscle performance. The data suggest that normalization of muscle metabolite content after refeeding improves muscle strength in malnourished subjects.

A paradoxical increase in resting energy expenditure in malnourished patients near death: the king penguin syndrome

BACKGROUND

The metabolic expression of extreme starvation on the verge of death is unknown in humans.

OBJECTIVE

The objective was to compare the resting energy expenditure (REE) of 5 extremely malnourished dying patients [body mass index (in kg/m(2)): 9.77 +/- 0.1] with that of 16 less-malnourished anorexia nervosa (AN) patients.

DESIGN

REE was measured by indirect calorimetry and body composition was measured by anthropometry and dual-frequency bioelectrical impedance analysis. Fasting serum insulin, thyroid hormone, and catecholamine concentrations were also determined.

RESULTS

At the start of refeeding, REE was high in each of the 5 extremely malnourished dying patients, whereas it was low in the 16 AN patients (mean +/- SD: 5174 +/- 391 kJ/d compared with 3844 +/- 619 kJ/d; P < 0.05). The high REE value in the 5 extremely malnourished dying patients was associated with almost no fat mass (FM), high urinary nitrogen loss (16.4 +/- 2.9 g/d), low serum fatty acid concentrations (0.36 +/- 0.23 mmol/L), and low or normal serum insulin, thyroid hormone, and catecholamine concentrations. During the first 2-4 wk of refeeding, REE and nitrogen loss decreased, whereas fatty acid concentrations increased in each of the 4 surviving patients; REE and urinary nitrogen output increased in the 16 AN patients.

CONCLUSION

In malnourished persons near death, there is an increase in REE and in protein catabolism. The reason for this increase is unknown but could relate to consumption of the last mobilizable muscle mass and to diseased cellular membranes.

Skeletal muscle dysfunction in chronic obstructive pulmonary disease and chronic heart failure: underlying mechanisms and therapy perspectives

Low exercise tolerance has a large influence on health status in chronic obstructive pulmonary disease and chronic heart failure. In addition to primary organ dysfunction, impaired skeletal muscle performance is a strong predictor of low exercise capacity. There are striking similarities between both disorders with respect to the muscular alterations underlying the impairment. However, different alterations occur in different muscle types. Histologic and metabolic data show that peripheral muscles undergo a shift from oxidative to glycolytic energy metabolism, whereas the opposite is observed in the diaphragm. These findings are in line with the notion that peripheral and diaphragm muscle are limited mainly by endurance and strength capacity, respectively. In both diseases, muscular impairment is multifactorially determined; hypoxia, oxidative stress, disuse, medication, nutritional depletion, and systemic inflammation may contribute to the observed muscle abnormalities and each factor has its own potential for innovative treatment approaches.

From malnutrition to refeeding during anorexia nervosa

Anorexia nervosa is one of the most common forms of malnutrition observed in Western society in individuals without physical diseases, with an average risk of mortality of 20% in a younger population aged between 15 and 25 years. It is characterised by an initial dramatic decrease in food intake that leads to profound depletion in muscle and fat mass. During the course of the disease, the resting energy expenditure decreases proportionally to the loss of lean body mass with a decrease in thyroid hormone secretion. The metabolic adaptation during anorexia nervosa is similar to that observed during starvation with a relative sparing of protein stores. After an initial weight loss, the total energy expenditure is similar to that in normal individuals, with a decrease in resting energy expenditure and an increased energy-related physical activity. At the end stage of wasting, however, physical activity dramatically decreases as well as energy intake. This metabolic adaptation of semi-starvation is impaired during refeeding with an increase in the thermic effect of food and a high risk of refeeding syndrome with severe hypophosphatemia.

Fasting in healthy individuals and adaption to undernutrition during chronic disease

During long-term fasting, gluconeogenesis from amino acids was thought to lessen, when ketone bodies from lipolysis became a major fuel source. Thus, muscle mass is conserved. However, recent studies show that this adaptation does not occur in chronic undernourishment. In cancer, chronic undernutrition without disease, and HIV infection, carbohydrate utilization is high. Enhanced hepatic glucose production occurs in active inflammatory bowel disease and in underweight cancer patients. Repletion of tissue after undernutrition is energetically inefficient because of enhanced diet induced thermogenesis (following anorexia nervosa) and decreased fat, and increased protein, oxidation (in tuberculosis).

The relationship between tissue loss and function: recent developments

Recent workers in this field have confirmed the complex interrelationship between structure and function. It is clear that the manner in which physiological impairment develops relative to compositional change depends on the setting within which malnutrition arises.