From the Center for Advanced Intestinal Rehabilitation, Boston Children's Hospital, Boston, MA.
the Center for Nutrition, Division of Gastroenterology, Hepatology and Nutrition, Boston Children's Hospital and Harvard Medical School, Boston, MA.
J Pediatr Gastroenterol Nutr. 2023 Oct 1;77(4):553-557. doi: 10.1097/MPG.0000000000003883. Epub 2023 Jul 27.
The nutritional status of children with intestinal failure (IF) can be difficult to determine using body weight and currently available anthropometric techniques. Air displacement plethysmography (ADP) is a noninvasive measure of whole-body composition that measures body mass and volume, with a calculation of percent body fat (%BF) and fat-free mass (FFM) that may be useful during the provision of specialized nutrition.
To evaluate the validity and feasibility of measuring body composition in children with IF using ADP compared with deuterium dilution (DD), as well as secondarily with other measures of body composition, namely bioelectrical impedance analysis (BIA), dual-energy X-ray absorptiometry (DXA), and four-site skinfold anthropometry.
We conducted a prospective cohort study of 18 children recruited through the Center for Advanced Intestinal Rehabilitation at Boston Children's Hospital. Patients 2-17 years of age with IF dependent on parenteral nutrition (PN) for more than 90 days were included. Spearman rank correlation and Bland-Altman limits of agreement (LOA) analysis were used to compare ADP to 4 alternative measures of body composition.
Eighteen children with IF, median age 7.1 [interquartile range (IQR) 5.4-9.3] years, 9 female (50%), and median residual bowel length 31 (IQR 22-85) cm were enrolled. Median PN energy intake was 46 (IQR 39-49) kcal/kg/day. Incomplete bladder emptying lead to invalid measures of DD in 4 subjects. Spearman correlation coefficients for %BF were low to moderate between ADP and DD ( r = 0.29), DXA ( r = 0.62), BIA ( r = 0.50), and skinfold ( r = 0.40). Correlations for FFM were high between ADP and these other measures (range 0.95-0.98). Comparing ADP with DD and skinfold measures, Bland-Altman analysis showed small mean bias (-1.9 and +1.5 kg) and acceptable 95% LOA ranges (10.7 and 22.9 kg), respectively, with larger bias (-10.7 and -7.7 kg) and LOA ranges (38.7 and 45.2 kg) compared to DXA and BIA. %BF by ADP and skinfold thickness were moderately correlated ( r = 0.43) with low bias (-0.2%) but very wide LOA (25.7%).
Body composition via ADP is feasible and valid in children with IF as a measure of FFM but appears less suitable for the measurement of %BF. The technique holds promise as a noninvasive measure of body composition to assess the efficacy of nutritional, medical, and surgical interventions.
使用体重和当前可用的人体测量技术来确定患有肠衰竭（IF）的儿童的营养状况可能具有挑战性。空气置换体描记法（ADP）是一种非侵入性的全身成分测量方法，可测量体重和体积，并计算体脂肪百分比（%BF）和去脂体重（FFM），这在提供专门营养时可能很有用。
评估使用 ADP 与氘稀释（DD）相比测量 IF 儿童身体成分的有效性和可行性，并次要地与其他身体成分测量方法（生物电阻抗分析（BIA）、双能 X 射线吸收法（DXA）和四点皮褶人体测量法）进行比较。
我们通过波士顿儿童医院先进肠道康复中心进行了一项前瞻性队列研究，共招募了 18 名患儿。纳入年龄在 2-17 岁之间，依赖肠外营养（PN）超过 90 天的 IF 患儿。使用 Spearman 秩相关和 Bland-Altman 限制协议（LOA）分析来比较 ADP 与 4 种替代身体成分测量方法。
18 名 IF 患儿，中位年龄 7.1 岁（四分位距 5.4-9.3），9 名女性（50%），中位残留肠长度 31 厘米（四分位距 22-85）。PN 能量摄入量中位数为 46（四分位距 39-49）千卡/公斤/天。4 名受试者因不完全排空膀胱而导致 DD 测量无效。ADP 与 DD（r=0.29）、DXA（r=0.62）、BIA（r=0.50）和皮褶（r=0.40）的 %BF 之间的 Spearman 相关系数为低到中度。ADP 与这些其他测量方法的 FFM 之间的相关性很高（范围为 0.95-0.98）。与 DD 和皮褶测量相比，Bland-Altman 分析显示平均偏差较小（-1.9 和+1.5 公斤），95%LOA 范围可接受（分别为 10.7 和 22.9 公斤），但与 DXA 和 BIA 相比，偏差较大（-10.7 和-7.7 公斤）和 LOA 范围较大（38.7 和 45.2 公斤）。ADP 和皮褶厚度的 %BF 中度相关（r=0.43），偏差较小（-0.2%），但 LOA 范围很宽（25.7%）。
ADP 作为 FFM 的测量方法，在 IF 儿童中是可行且有效的，但似乎不太适合测量 %BF。该技术有望成为评估营养、医学和手术干预效果的非侵入性身体成分测量方法。
