Pulmonary function correlates with body composition in Nigerian children and young adults with sickle cell disease.

Sickle cell disease (SCD) is associated with impaired growth and skeletal maturation. Decreased fat-free mass (FFM) and body fat (BF) have been reported in Nigerian children with SCD relative to healthy age- and gender-matched controls. Pulmonary abnormalities, including reduced forced vital capacity (FVC), forced expiratory volume in one second (FEV(1)) and total lung capacity (TLC), have also been described in children with SCD. Since undernutrition is common in sub-Saharan Africa, we were interested in knowing the relationship between pulmonary function and body composition in Nigerian children and young adults with SCD. Body composition was determined using bioelectrical impedance and pulmonary function was assessed by spirometry in Nigerian children and young adults aged 7-35 years (n = 102) as well as healthy age-and gender-matched controls (n = 104). Age-adjusted data revealed 19-26% lower FFM for male (P < 0.001) and female (P < 0.001) subjects with SCD relative to the controls. FVC, FEV(1) and PEF were also significantly reduced in male and female children and young adults with SCD compared to their control counterparts. For both male and female patients and controls, FVC, FEV(1) and PEF correlated positively with FFM (P < 0.001). PEF for the female subjects with SCD diverged progressively with increasing age relative to the controls and the rate of change was significantly lower (P < 0.001). We conclude that pulmonary function is reduced in Nigerian children and young adults with SCD compared to controls and that for both groups, pulmonary function is directly related to body composition. These findings underscore the need for early nutritional intervention for children with SCD.

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.