Ole Lander Svendsen

Does paracentesis of ascites influence measurements of bone mineral or body composition by dual-energy x-ray absorptiometry?

Measurements of bone mineral content (BMO) and density (BMD) by dual-energy x-ray absorptiometry (DXA) may be affected by changes in soft tissue overlying bone. Furthermore, the accuracy error for body composition determined by DXA may be high in the trunk region due to the complex bone geometry. Our objective was to evaluate the impact of paracentesis on measurements of bone mineral and body composition by DXA. DXA (Norland XR-36; Norland, Fort Atkinson, WI) scans were performed in six patients with cirrhosis of the liver before and after treatment of ascites by paracentesis. There were no significant differences in the spinal BMC (change [delta] = 0.04%) and BMD (delta = -0.9%) (P > .05), nor in total body BMC ([TBBMC] delta = 1.9%) and BMD ([TBBMD] delta = 0.4%) (P > .05). The median volume of ascites drained (6.8 L; range, 1.6 to 14.7) was not significantly different from the median change in total (5.8 kg; range, 2.0 to 16.1) or trunk lean tissue mass ([LTM] 5.8 kg; range, 1.9 to 11.9) (P > .05). The changes in body weight correlated with the changes in trunk LTM (r = .93, standard error of the estimate [SEE] = 1.8 kg, P = .007). Total and regional fat mass were not changed significantly by the paracentesis. We conclude that measurements of total body and spinal bone mineral by DXA are unaffected by large changes in the soft tissue composition and height of the trunk. Furthermore, the change in body composition induced by ascites drainage was accurately determined as a change in total body and trunk LTM on a group level.

Comparisons of leptin, incretins and body composition in obese and lean patients with hypopituitarism and healthy individuals

objective To identify possible abnormalities specific for obesity in hypopituitary patients.

Measurements of body composition by dual-energy X-ray absorptiometry improve prediction of energy expenditure.

Abstract: The prediction of energy expenditure by dual‐energy X‐ray absorptiometry (DXA) and bioimpedance analysis (BIA) was assessed in 35 healthy individuals of both sexes, with a mean body mass index (BMI) of 23.8 kg/m2 (range 18–33.8), and mean age of 30 years (22–40). Energy expenditure (EE) was measured under standard conditions in a respiration chamber, the total and regional body composition by DXA, and total body composition by BIA. When body composition was measured by BIA, 88.5% of the variation in 24‐h EE was explained by lean body mass (LBM); this figure was increased by DXA, where total lean tissue mass (LTM) and total fat tissue mass (FTM) could account for 91.5% of the variation. Also, the prediction of resting energy expenditure (REE) was improved by DXA, from 88.1% to 89.8% (LBM vs. LTM, FTM). Measurements of regional body composition showed that trunk LTM was significantly superior as a predictor, especially of REE and sleeping EE (EE sleep), compared to the peripheral LTM; thus, the predictions of REE were 83% vs. 87% (peripheral vs. trunk), respectively; and the predictions of EE sleep were 83% vs. 89% (peripheral vs. trunk), respectively. Therefore, body composition measurements by DXA improved the prediction of EE. Trunk LTM was a superior predictor, especially of REE and EE sleep, compared to peripheral LTM. In conclusion, the present results suggest that measuring total and regional body composition by DXA can somewhat improve the prediction of EE.

The impact of idiopathic childhood‐onset growth hormone deficiency (GHD) on bone mass in subjects without adult GHD

objectiveu2002 Despite seemingly adequate growth hormone (GH) treatment during childhood, children with GH deficiency (GHD) have reduced bone mineral density (BMD) at final height. The aim was to evaluate BMD and bone mineral content (BMC) in adults treated for idiopathic childhood‐onset (CO) GHD, 18 years after stopping GH treatment.