Department of Pediatrics and Child Health, Howard University, Washington, District of Columbia;
St. Jude Children's Research Hospital, Memphis, Tennessee;
Pediatrics. 2014 Sep;134(3):465-72. doi: 10.1542/peds.2014-0917.
Growth impairment is a known complication of sickle cell disease. Effects of hydroxyurea (HU) on growth in very young children are not known.
Height, weight, BMI, and head circumference (HC) were compared with World Health Organization (WHO) standards in BABY HUG, a multicenter, randomized, double-blinded, placebo-controlled 2-year clinical trial of HU in 193 children 9 to 18 months of age. Anthropometric data were closely monitored and converted to z scores by using WHO standardized algorithms for descriptive analyses. The treatment and placebo groups were compared longitudinally by using a mixed model analysis.
At entry, the z scores of BABY HUG children were higher than WHO norms. After 2 years of HU or placebo treatment, there were no significant differences between the groups, except for the mean HC z scores at study exit (HU: +0.8 versus placebo: +1.0, P = .05). Baseline z scores were the best predictors of z scores at study exit. The absolute neutrophil count, absolute reticulocyte count, and total white blood cell count had significant negative correlations with growth measures.
Both groups had normal or near normal anthropometric measures during the study. The HC z scores at study entry and exit were slightly greater than WHO norms. Higher baseline white blood cell count, absolute reticulocyte count, and absolute neutrophil count were associated with poorer growth. The significance of the slightly lower HC in the treatment group at study exit is not clear. Trends toward normalization of weight and height and effects on HC will be monitored in ongoing BABY HUG follow-up studies.
生长发育迟缓是镰状细胞病的已知并发症。羟基脲（HU）对非常年幼儿童生长的影响尚不清楚。
在 BABY HUG 中，比较了身高、体重、BMI 和头围（HC）与世界卫生组织（WHO）标准的差异，这是一项多中心、随机、双盲、安慰剂对照的 HU 治疗 9 至 18 个月大的儿童的 2 年临床试验。密切监测人体测量数据，并使用 WHO 标准化算法将其转换为 z 分数，用于描述性分析。使用混合模型分析对治疗组和安慰剂组进行纵向比较。
在 BABY HUG 儿童进入研究时，他们的 z 分数高于 WHO 标准。在 HU 或安慰剂治疗 2 年后，两组之间没有显著差异，除了研究结束时的平均 HC z 分数（HU：+0.8 与安慰剂：+1.0，P=0.05）。基线 z 分数是研究结束时 z 分数的最佳预测因子。绝对中性粒细胞计数、绝对网织红细胞计数和总白细胞计数与生长指标呈显著负相关。
在研究期间，两组的人体测量指标均正常或接近正常。研究开始和结束时的 HC z 分数略高于 WHO 标准。基线白细胞计数、绝对网织红细胞计数和绝对中性粒细胞计数较高与生长较差相关。在研究结束时，治疗组 HC 略低的意义尚不清楚。在正在进行的 BABY HUG 随访研究中，将监测体重和身高的正常化趋势以及对 HC 的影响。
