Discipline of Paediatrics and Child Health, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia.
Discipline of Paediatrics and Child Health, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia; Department of Gastroenterology, Sydney Children's Hospital Randwick, New South Wales, Australia.
J Cyst Fibros. 2023 Sep;22(5):851-856. doi: 10.1016/j.jcf.2023.06.003. Epub 2023 Jun 24.
Historically, body mass index (BMI) >50th percentile has represented optimal nutritional status in children with cystic fibrosis (CF) due to its positive association with lung function. Body composition parameters including fat-free mass index (FFMI) have been suggested as a more physiological nutrition benchmark.
(1) describe changes in body composition with age and gender; (2) assess the correlation between measures of nutritional status (FFMI-z, FMI-z, BMI-z) and lung function (forced expiratory volume in one second predicted; FEV1pp).
This retrospective, mixed cross-sectional and serial measures study consisted of children with CF (8 to 18 years) attending Sydney Children's Hospital (2007-2020). FFMI and fat mass index (FMI) were taken from biennial dual energy x-ray absorptiometry (DXA) scans. Z-scores were derived using Well's reference population [1]. Repeated measures correlation analyses assessed correlations between FFMI-z, FMI-z, and BMI-z with FEV1pp.
339 DXA reports were analysed from 137 patients. There were slight downwards trends in BMI-z and FMI-z, and an upwards trend in FFMI-z with increasing age and across both genders. Females had higher FMI-z and FFMI-z than males from 12.5 years. There was a weak, positive correlation between FEV1pp and BMI-z (r = 0.14, p = 0.04), and FFMI-z (r = 0.25, p<0.001). FMI-z had no correlation with FEV1pp (r=-0.06, p = 0.41).
Deficits in FFMI exist despite increasing trends with age. FFMI-z and BMI-z had a weak, positive correlation with FEV1pp. In contemporary cohorts, nutritional status (reflected by surrogate markers such as FFMI and BMI) may be less influential upon lung function than in previous decades. [1]: Wells, J.C., et al. Body-composition reference data for simple and reference techniques and a 4-component model: a new UK reference child. Am. J. Clin. Nutr.96, 1316-1326 (2012).
由于体重指数 (BMI) 超过第 50 百分位与肺功能呈正相关，因此在囊性纤维化 (CF) 儿童中，BMI 超过第 50 百分位曾代表最佳营养状态。体成分参数（包括去脂体重指数 (FFMI)）已被认为是更具生理学意义的营养基准。
(1) 描述身体成分随年龄和性别变化的情况；(2) 评估营养状况测量值（FFMI-z、FMI-z、BMI-z）与肺功能（一秒用力呼气量预测值；FEV1pp）之间的相关性。
本回顾性、混合性横断面和系列测量研究纳入了悉尼儿童医院 (2007-2020 年) 就诊的 8 至 18 岁 CF 患儿。FFMI 和脂肪量指数 (FMI) 来自每两年一次的双能 X 射线吸收法 (DXA) 扫描。使用 Wells 参考人群 [1] 得出 Z 分数。重复测量相关性分析评估了 FFMI-z、FMI-z 和 BMI-z 与 FEV1pp 的相关性。
对 137 名患者的 339 份 DXA 报告进行了分析。BMI-z 和 FMI-z 呈轻微下降趋势，FFMI-z 呈上升趋势，且随年龄增长和性别差异而变化。12.5 岁以后，女性的 FMI-z 和 FFMI-z 高于男性。FEV1pp 与 BMI-z(r=0.14，p=0.04) 和 FFMI-z(r=0.25，p<0.001) 呈弱正相关。FMI-z 与 FEV1pp 无相关性(r=-0.06，p=0.41)。
尽管 FFMI 随年龄增长呈上升趋势，但仍存在不足。FFMI-z 和 BMI-z 与 FEV1pp 呈弱正相关。在当代队列中，营养状况（通过 FFMI 和 BMI 等替代标志物反映）对肺功能的影响可能低于前几十年。[1]：Wells, J.C., 等人。简单和参考技术以及 4 分量模型的体成分参考数据：英国新参考儿童。Am. J. Clin. Nutr.96, 1316-1326 (2012)。
