Division of Nephrology, Children's National Hospital/Department of Pediatrics, George Washington School of Medicine, 111 Michigan Ave, Washington, NWDC, USA.
Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
Pediatr Nephrol. 2023 Dec;38(12):4145-4156. doi: 10.1007/s00467-023-06047-0. Epub 2023 Jul 19.
Collagen X biomarker (CXM) is a novel biomarker of linear growth velocity. We investigated whether CXM correlated with measured growth velocity in children with impaired kidney function.
We used data from children aged 2 through 16 years old enrolled in the Chronic Kidney Disease in Children (CKiD) study. We assessed the association between CXM level and growth velocity based on height measurements obtained at study visits using linear regression models constructed separately by sex, with and without adjustment for CKD covariates. Linear mixed-effects models were used to capture the between-individual and within-individual CXM changes over time associated with concomitant changes in growth velocity from baseline through follow-up.
A total of 967 serum samples from 209 participants were assayed for CXM. CXM correlated more strongly in females compared to male participants. After adjustment for growth velocity and CKD covariates, only proteinuria in male participants affected CXM levels. Finally, we quantified the between- and within-participant associations between CXM level and growth velocity. A between-participant increase of 24% and 15% in CXM level in females and males, respectively, correlated with a 1 cm/year higher growth velocity. Within an individual participant, on average, 28% and 13% increases in CXM values in females and males, respectively, correlated with a 1 cm/year change in measured growth.
CXM measurement is potentially a valuable aid for monitoring growth in pediatric CKD. However, future research, including studies of CXM metabolism, is needed to clarify whether CXM can be a surrogate of growth in children with CKD. A higher resolution version of the Graphical abstract is available as Supplementary information.
胶原蛋白 X 标志物（CXM）是线性生长速度的新型生物标志物。我们研究了 CXM 是否与肾功能受损儿童的测量生长速度相关。
我们使用了来自慢性肾脏病儿童（CKiD）研究的 2 至 16 岁儿童的数据。我们使用线性回归模型，分别按性别构建，同时调整 CKD 协变量和不调整 CKD 协变量，评估了 CXM 水平与生长速度之间的相关性，基于研究访问时的身高测量值。线性混合效应模型用于捕获与基线至随访期间生长速度同时变化相关的个体间和个体内 CXM 变化。
对 209 名参与者的 967 份血清样本进行了 CXM 测定。与男性参与者相比，女性参与者的 CXM 相关性更强。在调整生长速度和 CKD 协变量后，只有男性参与者的蛋白尿会影响 CXM 水平。最后，我们量化了 CXM 水平与生长速度之间的个体间和个体内相关性。女性和男性的 CXM 水平分别增加 24%和 15%，与生长速度提高 1cm/年相关。在个体参与者中，女性和男性的 CXM 值平均分别增加 28%和 13%，与测量生长速度的 1cm/年变化相关。
CXM 测量可能是监测儿科 CKD 生长的有价值的辅助手段。然而，需要进一步的研究，包括 CXM 代谢的研究，以阐明 CXM 是否可以作为 CKD 儿童生长的替代指标。更详细的图表可在补充信息中查看。
