Bioelectrical impedance analysis of the body composition of children and adolescents with sickle cell disease

Bioimpedance Resistance Indices and Cell Membrane Capacitance Used to Assess Disease Status and Cell Membrane Integrity in Children with Nephrotic Syndrome

Background

Accumulation of extracellular water (ECW) is a major clinical manifestation of nephrotic syndrome (NS) in children. Bioimpedance spectroscopy (BIS) is a simple, noninvasive technique that reflects body water volumes. BIS can further measure cell membrane capacitance (C_M), which may be altered in NS. The aims of the study were to explore how BIS measurements could reflect disease status in NS, while avoiding prediction equations which are often only validated in adult populations.

Methods

The study involved 8 children (2-10 years) with active NS (ANS group), 5 of which were also studied at NS remission (NSR group), as well as 38 healthy children of similar age (HC group). BIS measurements determined resistances R_INF, R_E, and R_I (reflecting total body water, extracellular water, and intracellular water) and C_M. Also resistance indices based on height (H) were considered, RI = H²/R.

Results

It was found that R_E and R_INF were significantly lower in the ANS group than in both NSR and HC groups (p < 0.001). Corresponding resistance indices were significantly higher in the ANS group than in the NSR (p < 0.01) and the HC (p < 0.05) groups, in accordance with elevated water volumes in NS patients. Indices of intracellular water were not significantly different between groups. C_M was significantly lower in the ANS group than in NSR and HC groups (p < 0.05).

Conclusion

BIS could distinguish children with active NS from well-treated and healthy children. Studies with more children are warranted.

Bioelectric impedance analysis of body composition of children and adolescents with sickle cell anemia in Enugu, Nigeria

BACKGROUND

Body composition indices are widely used to evaluate growth and nutrition in children, particularly those with sickle cell anemia (SCA), who are known to have impaired growth, impaired skeletal maturation, and delayed puberty. The current study is aimed at determining the body composition of children with SCA.

METHODS

Consecutive selection of SCA children aged 6 to 18 years, who served as subjects and their age and gender matched children with HbAA (controls), selected using multi-stage systematic sampling. It was a cross-sectional descriptive study conducted at the pediatric hematology and oncology clinic. Bioelectric impedance analysis was used to determine the body composition parameters, including weight, body fat percentage (BFP), visceral fat percentage, body mass index (BMI), skeletal muscle percentage, and resting metabolic rate. Data were analyzed using SPSS 16.0 at P < 0.05.

RESULTS

One hundred and thirty-two subjects and controls respectively were studied. Subjects had lower body composition parameters compared with controls, with the older male subjects aged 10 to 18 years, having lower body composition indices (weight, height, BMI, and BFP) compared with controls. Visceral fat percentage was low in both subjects and controls.

CONCLUSIONS

Children with SCA, particularly the older males, have impaired body composition indices. There is a need to conduct further studies to determine the longitudinal aspects of growth as well as quantitative and qualitative assessment of nutritional intake in children with SCA, which will inform higher alimentation requirements for HbSS children as compared with HbAA individuals.

Evaluation of panoramic radiomorphometric indices related to low bone density in sickle cell disease

SUMMARY

In sickle cell disease, erythroid hyperplasia causes trabecular destruction leading to low bone density. This condition could be suspected by the radiomorphometric indices and your diagnosis becomes relevant in a multidisciplinary context of health care for sickle cell subjects, providing prognostics and contributing to determine adequate therapeutic and preventive actions.

INTRODUCTION

The aim of this study was to assess the risk of low bone density in subjects with sickle cell disease (SCD) through analysis of panoramic radiographic exams by radiomorphometric indices.

METHODS

Seventy-eight Brazilian subjects with SCD took part in this study and were subdivided into four groups: (I) 31 SCD subjects aged under 40 years; (II) 13 SCD subjects aged 40 years or more; (III) 12 normal subjects aged under 40 years; and (IV) 22 normal subjects aged 40 years or more. In the panoramic radiographs, the mandibular cortical index (MCI) classification, increased spacing of the trabecular bone, panoramic mandibular index (PMI), and mental index (MI) were evaluated. Exact Fisher's test was used to compare age between the different groups. Descriptive analysis of the data was performed to evaluate the simple visual estimation of low bone density (increased bone trabecular space and MCI), and a one-way analysis of variance (Bonferroni criteria) was used to compare the means of the quantitative indices (PMI and MI). The significance level was p < 0.05.

RESULTS

In the MCI classification, C2 was more prevalent, especially in groups I and IV. Increased spacing of the trabecular bone was more frequent in groups I and II. MI did not show a statistically significant difference among the groups. PMI showed a statistically significant difference only between groups III and IV.

CONCLUSIONS

The radiomorphometric indices applied in the present study can be used on panoramic radiographs to detect the presence of low bone density in SCD subjects.

A cross-sectional study of the growth characteristics of Nigerian infants from birth to 2 years of age

Malnutrition compromises the growth of children in sub-Saharan Africa. In Nigeria, the prevalence of childhood malnutrition approaches 40%. There are few reports relating the growth characteristics of breast-fed Nigerian infants to the anthropometric properties of their mothers. A total of 100 urban and rural mother/baby pairs were recruited. The mean BMI values of the urban and rural mothers were 24.2 and 21.3 kg m(-2), respectively. The mean length, weight and head circumference of the rural infants were significantly lower than those of the urban infants. Z-scores based on World Health Organization standards showed: (i) length-for-age z-score <-2 in urban (27%) and rural (33%) children; (ii) a higher incidence of underweight and small HC in rural (33%; and 13%) versus urban children (12% and 0%); and (iii) positive correlations between all three z-scores and maternal BMI. Negative correlations were observed between infant age and z-scores for length-for-age, weight-for-age and HC-for-age.

Nutritional status and delirium in long-term care elderly individuals

Delirium is physiologically plausible in elderly individuals with a poor nutritional status. We explored body composition, serum protein levels, and delirium in a multicenter long-term care study using bioelectrical impedance analysis (BIA). Estimates from the BIA procedure included the body cell mass and fat-free mass (FFM) of nursing home elderly residents (N = 312). Increased delirium was identified in men and women who were leaner and had lower FFM. Clinical surveillance for delirium in frail elderly individuals with low serum albumin levels and polypharmacy is recommended because of their increased likelihood of having drug toxicities for medications with protein-binding properties.

Assessment of the bone quality of black male athletes using calcaneal ultrasound: a cross-sectional study

BACKGROUND

Lifestyle, genetics and environmental factors are established determinants of bone density. We aimed to describe the bone characteristics of competitive top-ranked Nigerian male athletes using calcaneal ultrasound and to assess whether intensive training promotes higher bone density in an environment with reportedly low calcium intake; to compare the bone characteristics of footballers with runners and other sportsmen; and to assess the correlation of stiffness index (SI) with activity level, since energy expenditure correlates with length of training and by extension, magnitude of skeletal loading.

METHODS

We recruited 102 male athletes: these included football (n = 68), running (n = 15), handball (n = 7), taekwando (n = 6), cycling (n = 2), judo (1), badminton (1) and high jump (1). Anthropometric data were first recorded on a structured form and energy expenditure was indirectly estimated with a validated questionnaire. Bone density was assessed using the Lunar Achilles+ calcaneal ultrasonometer.

RESULTS

The mean age of athletes was 25 +/- 6 years. The means of BMI and energy expenditure were 21.9 +/- 2.0 kg/m2 and 35.0 +/- 13.7 kcal/kg/day, respectively. Footballers were younger (p < 0.001) and heavier (p < 0.001) than runners. Football was a significant determinant of BUA independent of age, BMI and energy expenditure (p = 0.001). Football was also a significant determinant of SOS independent of age, height, weight and BMI (p < 0.001). The mean SI was 127 +/- 16 and the median T-score was 0.82 (-1.88, 3.35). The mean SI of footballers (130 +/- 15), runners (130 +/- 12) and other sportsmen (115 +/- 18) differed significantly (p = 0.001). Multivariate analyses revealed that football (p < 0.001) and running (p < 0.001) were significant determinants of SI independent of age and BMI. Footballers when compared with other sportsmen had a higher mean SI independent of age and BMI (p < 0.001). Age was not correlated with SI. The median T-score of footballers, 0.94 (-1.0, 3.35) was higher than that of other sportsmen.

CONCLUSION

Repetitive skeletal loading at the heel has the potential to improve bone density in black male athletes. The magnitude of increase may be higher in medium impact sports such as soccer and running compared with low or non-impact sports such as judo or taekwando, and is independent of age and BMI. However, future longitudinal data will be required to support our observations.

Phase angle correlates with n-3 fatty acids and cholesterol in red cells of Nigerian children with sickle cell disease

OBJECTIVE

To determine the cholesterol content and fatty acid composition of red cell membrane phospholipids (PL) of children with sickle cell disease (SCD) and to correlate these levels with whole body phase angle that is related to the integrity and function of cell membranes.

STUDY DESIGN

Blood samples were obtained from 69 children with SCD and 72 healthy age- and gender-matched controls in Nigeria for the determination of the cholesterol content and proportions of fatty acids in red cell PL. Bioelectrical impedance analysis was used to obtain resistance (R) and reactance (Xc) from which phase angle was calculated as arctan Xc/R. Cholesterol (normalized to lipid phosphorus) and the proportions of individual fatty acids were correlated with phase angle.

RESULTS

The proportions of palmitic (p < 0.001), stearic acid (p = 0.003) and cholesterol (p < 0.001) were significantly higher in the red cells of children with SCD, whereas the proportions of arachidonic acid and docosahexaenoic acid were reduced (p = 0.03 and < 0.001, respectively) compared to controls. The phase angle was inversely correlated with the proportions of palmitic acid (p = 0.03) and oleic acid (p < 0.001) and cholesterol (p = 0.003). Three n-3 polyunsaturated fatty acids-eicosapentaenoic acid, docosapentaenoic acid and docosahexaenoic acid- were positively correlated with phase angle (p < 0.001).

CONCLUSIONS

The fatty acid composition and cholesterol content of tissue membranes in SCD correlate with the phase shift measured by bioelectrical impedance analysis. Phase angle measurements may provide a non-invasive method for monitoring interventions aimed at altering the lipid composition of membranes.

Correlation of the fatty acid composition and fluid property of the cholesteryl esters in the serum of Nigerian children with sickle cell disease and healthy controls

In a previous study conducted in Nigeria, we found that children with sickle cell disease (SCD) had exceedingly low total serum cholesterol levels (mean=100-102mg/dl). The fact that significant reductions in the levels of certain polyunsaturated fatty acids (PUFA) have been documented in the serum phospholipids of these same SCD subjects led us to inquire as to the fatty acid composition of the cholesteryl esters (CE) in their serum. Lecithin:cholesterol acyl transferase (LCAT), the enzyme in blood that catalyzes the reaction in which tissue cholesterol is acylated prior to its removal from cell membranes, is relatively specific for certain PUFA. CE in blood serum from 43 male and 42 female children with SCD, ages 4-18 years, and equal numbers of age- and gender-matched controls were analyzed for their fatty acid composition. Relative to the non-SCD controls, the CE of the SCD subjects contained 9% less linoleic acid, 16% less arachidonic acid, 40% less alpha-linolenic acid, 50% less eicosapentaenoic acid, and 36% less docosahexaenoic acid, but 15% more palmitic acid and 10% more oleic acid. Overall, the acyl chains of the CE of the SCD subjects were less fluid than those of the controls, as determined by comparison of their mean melting points (MMP) and double bond indices (DBI). MMP and DBI were both estimated from the individual constituent fatty acids comprising the CE acyl chains. The strongest correlations between MMP and fatty acid mole percent were seen with palmitic acid and linoleic acid. These results show that the fatty acid composition of the serum CE of children with SCD is abnormal relative to controls who do not have this hematologic disorder. We speculate that suboptimal fatty acid nutrition in Nigerian children with SCD compromises their ability to remove cholesterol from their tissues due to preference of the LCAT enzyme for PUFA, thereby accounting, in part at least, for the low total serum cholesterol levels one finds in children with SCD.