Brennan B M, Rahim A, Blum W F, Adams J A, Eden O B, Shalet S M
Department of Paediatric Oncology, Royal Manchester Children's Hospital, UK.
Clin Endocrinol (Oxf). 1999 Feb;50(2):163-9. doi: 10.1046/j.1365-2265.1999.00622.x.
In order to explore the mechanism of obesity in long-term survivors of childhood leukaemia, fat mass, lean body mass and serum leptin were assessed in a cohort of 32 (17 males) adults who had received cranial irradiation (XRT) in childhood as part of their treatment for acute lymphobiastic leukaemia (ALL), and compared with 35 age and body mass index (BMI) matched young adults (18 male).
Thirty-one patients and 18 controls had fat mass and lean body mass assessed by dual x-ray absorptiometry (DEXA), using a lunar DPX-L scanner. Serum leptin concentrations were also measured in 27 patients and all controls. Growth hormone status had previously been determined using an insulin tolerance test and arginine stimulation test. Nine patients were classified as severe growth hormone (GH) deficient (group 1), 12 patients as GH insufficient (group 2) and 11 patients as normal (group 3).
BMI and absolute fat mass were not significantly different between the patients and controls regardless of their gender (P = 0.1 and P = 0.14 respectively). In contrast, absolute lean mass was significantly reduced (P < 0.01) and leptin concentrations were significantly increased (P < 0.001) in patients compared with controls. BMI, fat mass and leptin concentrations but not lean mass were significantly different between the three GH status groups (P < 0.01, P < 0.01, P = 0.004, and P = 0.67 respectively). When leptin concentrations were expressed per unit of fat mass, they were increased in the patients compared with the controls (P = 0.03) with significant differences between the GH status groups (P = 0.004), being significantly higher in the severe GH deficient group.
Young adults who receive cranial irradiation in childhood are prone to GH deficiency and hyperleptinaemia. The pathophysiological significance of the hyperleptinaemia remains to be established but it has occurred either as a consequence of radiation induced hypothalamic damage or GH deficiency.
为探究儿童白血病长期存活者肥胖的机制，对32名（17名男性）成年患者进行了脂肪量、瘦体重及血清瘦素评估，这些患者童年时因急性淋巴细胞白血病（ALL）接受过颅脑照射（XRT）治疗，将其与35名年龄和体重指数（BMI）匹配的年轻成年人（18名男性）作比较。
31名患者和18名对照者使用Lunar DPX-L扫描仪通过双能X线吸收法（DEXA）评估脂肪量和瘦体重。还对27名患者和所有对照者测量了血清瘦素浓度。先前已通过胰岛素耐量试验和精氨酸刺激试验确定生长激素状态。9名患者被归类为严重生长激素（GH）缺乏（第1组），12名患者为GH不足（第2组），11名患者正常（第3组）。
无论性别如何，患者与对照者之间的BMI和绝对脂肪量均无显著差异（分别为P = 0.1和P = 0.14）。相比之下，与对照者相比，患者的绝对瘦体重显著降低（P < 0.01），瘦素浓度显著升高（P < 0.001）。三个GH状态组之间的BMI、脂肪量和瘦素浓度有显著差异，但瘦体重无显著差异（分别为P < 0.01、P < 0.01、P = 0.004和P = 0.67）。当按每单位脂肪量表示瘦素浓度时，与对照者相比，患者的瘦素浓度升高（P = 0.03），GH状态组之间有显著差异（P = 0.004）,在严重GH缺乏组中显著更高。
童年时接受颅脑照射的年轻成年人易患GH缺乏和高瘦素血症。高瘦素血症的病理生理意义尚待确定，但它可能是辐射诱导的下丘脑损伤或GH缺乏的结果。
