Department of Epidemiology and Preventive Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1, Sakuragaoka, Kagoshima, 890-8544, Japan.
BMC Cancer. 2017 Oct 16;17(1):687. doi: 10.1186/s12885-017-3681-y.
High birth weight (BW), 4000 g or larger, is an established risk factor for childhood leukemia. However, its association with central nervous system (CNS) tumor risk is yet unclear. The present study examined it, analyzing data obtained from a case-control study conducted among three states from the US. The association with childhood leukemia risk was also further examined.
In this study, a data set provided by the Comprehensive Epidemiologic Data Resource was analyzed with an official permission. The original case-control study was conducted to examine the association between paternal preconception exposure to ionizing radiation and childhood cancer risk. Cases with childhood cancer were mainly ascertained from local hospitals, and controls were selected, matched with birth year (1-year category), county of residence, sex, ethnicity and maternal age (+/-2 years). Since the ID numbers were unavailable, conventional logistic analyses were conducted adjusting for those matching variables except for the county of residence. In addition to those variables, gestational age, age at diagnosis and study sites as covariables were included in the logistic models.
Analyzed subjects were 72 CNS tumor cases, 124 leukemia cases and 822 controls born from 1945 to 1989. The odds ratios (ORs) of CNS tumor risk for children with low BWs (<2500 g) and high BWs (>4000 g) were 2.0 (95% confidence interval [CI]) = 0.7, 5.9) and 2.5 (95%CI = 1.2, 5.2)], respectively. When high-BW children were restricted to those who were large for gestational age (LGA), the OR for high-BW children remained similar (OR = 2.7; 95%CI = 1.1, 6.2). On the other hand, the ORs of leukemia risk for children with low and high BWs were 0.8 (95%CI = 0.2, 3.0) and 1.4 (95%CI = 0.7, 2.6), respectively. In the normal range of BW (2500-4000 g), higher BW was positively associated with CNS tumor risk (beta = 0.0011, p for trend = 0.012). However, the association with leukemia risk was not significant (beta = -0.0002, p for trend = 0.475).
High-BW and LGA children had an elevated childhood CNS tumor risk. In the normal BW range, the BW itself was positively related to CNS tumor risk. No significant association between BW and childhood leukemia risk was observed in this study.
高出生体重（BW），即 4000 克或以上，是儿童白血病的既定危险因素。然而，其与中枢神经系统（CNS）肿瘤风险的关联尚不清楚。本研究对此进行了检验，分析了在美国三个州进行的一项病例对照研究中获得的数据。同时还进一步检验了其与儿童白血病风险的关联。
本研究使用官方授权的数据集进行分析。该原始病例对照研究旨在检验父亲孕前暴露于电离辐射与儿童癌症风险之间的关系。病例主要从当地医院确定，对照则按照出生年份（1 年为一个类别）、居住县、性别、种族和母亲年龄（+/-2 岁）进行选择匹配。由于无法获取身份识别号码，因此在调整了除居住县以外的匹配变量后，采用常规逻辑分析进行了分析。除了这些变量外，还将胎龄、诊断时的年龄和研究地点作为协变量纳入逻辑模型。
分析对象为 72 例 CNS 肿瘤病例、124 例白血病病例和 822 例出生于 1945 年至 1989 年的对照。低 BW（<2500 克）和高 BW（>4000 克）儿童的 CNS 肿瘤风险的比值比（OR）分别为 2.0（95%置信区间[CI]）= 0.7，5.9）和 2.5（95%CI = 1.2，5.2）。当将高 BW 儿童限制为巨大儿（LGA）时，高 BW 儿童的 OR 仍相似（OR = 2.7；95%CI = 1.1，6.2）。另一方面，低 BW 和高 BW 儿童的白血病风险 OR 分别为 0.8（95%CI = 0.2，3.0）和 1.4（95%CI = 0.7，2.6）。在 BW 的正常范围内（2500-4000 克），较高 BW 与 CNS 肿瘤风险呈正相关（β= 0.0011，趋势检验的 p 值= 0.012）。然而，与白血病风险的关联并不显著（β= -0.0002，趋势检验的 p 值= 0.475）。
高 BW 和 LGA 儿童的儿童 CNS 肿瘤风险增加。在 BW 的正常范围内，BW 本身与 CNS 肿瘤风险呈正相关。本研究未观察到 BW 与儿童白血病风险之间存在显著关联。
