Mishra Kirtisudha, Datta Vikram, Aarushi Aarushi, Kaur Narula Maninder, Iyer R Subramanyam, Nangia Sushma
Department of Pediatrics.
Department of Neonatology, Lady Hardinge Medical College, New Delhi, India.
Iran J Pediatr. 2014 Feb;24(1):93-9. Epub 2013 Jan 29.
The association of low birth weight (LBW) with adult onset diseases like hypertension is suggested to be partially mediated by a low number of nephrons at birth. Studies have established a relation between LBW and renal volume as the latter is a surrogate marker of total nephron number. Most such studies have considered birth weight or gestational age as separate independent predictors, without taking into consideration the baby's weight with respect to its gestational age. This study aims to investigate the influence of weight for gestational age on kidney volume in newborns.
Consecutive newborns delivered in the department of neonatology in a tertiary care medical college and hospital, were included in a cross-sectional study. The subjects were classified as appropriate for gestational age (AGA) and small for gestational age (SGA) as per Lubchenco's charts of weight for gestational age (WGA). Bilateral kidney dimensions were measured by a single observer and combined kidney volumes were calculated and compared between the groups. Findings : Four hundred and seventeen newborns (SGA 159; AGA 258) were included. The mean combined kidney volume (CKV) was significantly lower among SGA newborns (13.85±4.02 cm(3)) compared to that of AGA (16.88±4.53 cm(3)) (P<.001). Univariable and multivariable analyses were done for assessing the effect of demographic, anthropometric and maternal parameters on CKV. WGA, crown heel length, gestational age and postnatal age (hours of life) were independent predictors of mean CKV. An SGA newborn was expected to have a mean CKV 1.57 cm less (95% CI -2.49 cm to -0.65 cm) than that of its AGA counterpart.
Considering the future implications of being SGA and having low kidney volumes at birth, it is essential to have an objective depiction of the relationship between these two vital parameters. This study from the Indian subcontinent brings forth such an association.
低出生体重（LBW）与成人期疾病如高血压之间的关联被认为部分是由出生时肾单位数量少介导的。研究已确立低出生体重与肾体积之间的关系，因为肾体积是总肾单位数量的替代标志物。大多数此类研究将出生体重或孕周视为单独的独立预测因素，而未考虑婴儿体重相对于其孕周的情况。本研究旨在探讨出生体重相对于孕周对新生儿肾体积的影响。
在一所三级医疗学院和医院的新生儿科连续分娩的新生儿被纳入一项横断面研究。根据卢申科的出生体重相对于孕周（WGA）图表，将受试者分为适于胎龄（AGA）和小于胎龄（SGA）。由一名观察者测量双侧肾脏尺寸，并计算合并肾体积，然后在两组之间进行比较。结果：纳入417例新生儿（SGA 159例；AGA 258例）。SGA新生儿的平均合并肾体积（CKV）（13.85±4.02 cm³）显著低于AGA新生儿（16.88±4.53 cm³）（P<0.001）。进行单变量和多变量分析以评估人口统计学、人体测量学和母体参数对CKV的影响。WGA、顶臀长度、孕周和出生后年龄（生命小时数）是平均CKV的独立预测因素。预计SGA新生儿的平均CKV比其AGA对应者少1.57 cm（95%CI -2.49 cm至-0.65 cm）。
考虑到SGA以及出生时肾体积低的未来影响，客观描述这两个重要参数之间的关系至关重要。来自印度次大陆的这项研究揭示了这种关联。
