Body composition of chronic renal patients: anthropometry and bioimpedance vector analysis

Prevalence of sarcopenia and associated factors in patients in hemodialysis

Objective: To assess the prevalence of sarcopenia and associated factors in patients with chronic kidney disease (CKD) undergoing hemodialysis (HD). Methods: This cross-sectional study evaluated patients with CKD undergoing HD from January to October 2016 in two dialysis centers located in Recife, Pernambuco. For the diagnosis of sarcopenia, the criteria proposed by the 2019 European Consensus on Sarcopenia, which advocates low muscle strength as the main criterion, were considered. Demographic, clinical, anthropometric, and behavioral covariates were evaluated. Results: 108 patients were included, with a mean age of 51.4 ± 17.0 years and homogeneous distribution between the sexes.Sarcopenia was present in 38.9% of the population, of which 69% had severe sarcopenia. A higher prevalence of sarcopenia was observed among men (60% vs. 17%; p < 0.001), in those without a partner (48.1% vs. 30.4%; p < 0.045), in smokers (50% vs. 30%; p < 0.034), with low weight (underweight 73.3%, eutrophic 33.9%, overweight 32.4%; p = 0.001) and those with normal albumin levels (47.5% vs. 28.6%; p = 0.045). Conclusion: Approximately one in three nephropathic patients on hemodialysis presented sarcopenia and, among these, most had the severe form of this condition.Uremic sarcopenia was more prevalent in males, in individuals without partners, underweight, in smokers, and among those with normal albumin levels.

BIOELECTRICAL VECTOR ANALYSIS IN OBESE ADOLESCENTS

OBJECTIVE

To evaluate the hydration of obese and non-obese adolescents by vectorial bioimpedance analysis, in addition to verifying the associations between obesity and bioelectrical impedance vectorial analysis (BIVA) parameters.

METHODS

A cross-sectional study with adolescents between 14 and 18 years old (n=489, 300 boys and 189 girls). Electric bioimpedance (BIA; Quantum_II, RJL system, Rome, Italy) provided resistance and reactance parameters to calculate phase angle (PA), fat-free mass (FFM) and body fat (%BF). The confidence ellipses were compared, and the construction of the tolerance ellipses allowed individual and qualitative evaluation of the vectors and classification in dehydrated, normohydrated and hyperhydrated.

RESULTS

78 obese and 411 eutrophic adolescents participated. Resistance (p<0.001) and reactance (p<0.001) and their normalization by stature (p<0.001) were reduced in the obese, whereas the PA was higher (p=0.003). %BF was 11.3% higher in obese adolescents. The main vector of the obese, both male (D=1.38; p<0.001) and female (D=1.49; p<0.001), indicated greater hydration. The ellipse of tolerance of the total sample showed that 25 (32.1%) were hyperhydrated and 02 (2.6%) vectors positioned in the sense of dehydration. A total of 17 (53.2%) girls and 16 (34.8%) boys were hyperhydrated. Logistic regression showed an inverse relation of BMI with resistance (p<0.001), reactance (p<0.001) and both normalized by stature. Adolescents with increased PA (p<0.001) were twice as likely to present obesity.

CONCLUSIONS

Obese adolescents were hyperhydrated and there was an inverse relationship of BMI with resistance and direct with PA.

Chronic kidney disease: considerations for monitoring skeletal muscle health and prescribing resistance exercise

Skeletal muscle wasting has gained interest as a primary consequence of chronic kidney disease (CKD) due to the relationship between skeletal muscle mass, mortality and major adverse cardiovascular events in this population. The combination of reductions in physical function, skeletal muscle performance and skeletal muscle mass places individuals with CKD at greater risk of sarcopenia. Therefore the monitoring of skeletal muscle composition and function may provide clinical insight into disease progression. Dual-energy X-ray absorptiometry and bioelectrical impedance analysis are frequently used to estimate body composition in people with CKD within clinical research environments, however, their translation into clinical practice has been limited. Proxy measures of skeletal muscle quality can be obtained using diagnostic ultrasound, providing a cost-effective and accessible imaging modality to aid further clinical research regarding changes in muscle composition. Clinicians and practitioners should evaluate the strengths and limitations of the available technology to determine which devices are most appropriate given their respective circumstances. Progressive resistance exercise has been shown to improve skeletal muscle hypertrophy of the lower extremities, muscular strength and health-related quality of life in end-stage renal disease, with limited evidence available in CKD predialysis. Fundamental principles (i.e. specificity, overload, variation, reversibility, individuality) can be used in the development of more advanced programs focused on improving specific neuromuscular and functional outcomes. Future research is needed to determine the applicability of skeletal muscle monitoring in clinical settings and the feasibility and efficacy of more advanced resistance exercise approaches in those with CKD predialysis.

Physical Therapy Considerations for Chronic Kidney Disease and Secondary Sarcopenia

Chronic kidney disease (CKD) is a progressive condition that may negatively affect musculoskeletal health. These comorbidities may include malnutrition, osteoporosis, and decreased lean body mass. Secondary sarcopenia due to CKD may be associated with mobility limitations and elevated fall risk. Physical therapists are well-positioned among the health care team to screen for secondary sarcopenia in those with CKD and for the treatment of musculoskeletal comorbid conditions that may affect functional performance. Given the consequences of both low muscle mass and low bone mineral density, appropriate and timely physical therapy is important for fall risk assessment and intervention to minimize the susceptibility to bone fracture. While strength training has been studied less frequently than aerobic training for the management of secondary CKD conditions, evidence suggests that this patient population benefits from participation in strength training programs. However, the provision of a formal exercise prescription by a health care professional, along with formal implementation of an exercise program, may need to be more fully integrated into the standard plan of care for individuals with CKD.

Body composition in adults with neurofibromatosis type 1

Objective

To evaluate the body composition and nutritional status of neurofibromatosis type 1 (NF1) adult patients.

Method

A cross-sectional study of 60 NF1 patients (29 men, 31 women) aged ≥ 18 years who were evaluated from September 2012 to September 2013 in a Neurofibromatosis Outpatient Reference Center. Patients underwent nutritional assessment including measurements of weight, stature, waist circumference (WC), upper-arm circumference (UAC), and skinfolds (biceps, triceps, subscapular, suprailiac). Body mass index (BMI), upper-arm total area (UATA), upper-arm muscle area (UAMA), upper-arm fat area (UAFA), body fat percentage (BFP), fat mass, fat-free mass, fat mass index, and fat-free mass index were also calculated.

Results

The mean age of the study population was 34.48±10.33 years. The prevalence of short stature was 28.3%. Low weight was present in 10% of the sample and 31.7% of patients had a BMI ≥ 25 kg/m2. Reduced UAMA (<5th percentile) was present in 43.3% and no difference was found in UAFA between the sexes. The BFP was considered high in 30% and 17 (28.3%) patients had a WC above the World Health Organization cutoffs.

Conclusion

In this study, NF1 patients had a high prevalence of underweight, short stature, and reduced UAMA, with no difference between the sexes. Reduced UAMA was more prevalent in underweight patients; however, this was also observed in the normal and overweight patients. Further studies should investigate the distribution of body tissues in NF1 patients, including differences between men and women, and the influence of diet and nutrition on clinical features in NF1.