Hill Rebecca J, Brookes Denise S K, Lewindon Peter J, Withers Geoffrey D, Ee Looi C, Connor Frances L, Cleghorn Geoffrey J, Davies Peter S W
University of Queensland, Children's Nutrition Research Centre, Discipline of Paediatrics and Child Health, Royal Children's Hospital, Herston, QLD 4029, Australia.
J Pediatr Gastroenterol Nutr. 2009 May;48(5):538-43. doi: 10.1097/MPG.0b013e31818cb4b6.
Clinical results of bone mineral density for children with inflammatory bowel disease are commonly reported using reference data for chronological age. It is known that these children, particularly those with Crohn disease, experience delayed growth and maturation. Therefore, it is more appropriate to compare clinical results with bone age rather than chronological age.
Areal bone mineral density (aBMD) was measured using dual energy x-ray absorptiometry, and bone age was assessed using the Tanner-Whitehouse 3 method from a standard hand/wrist radiograph. Results were available for 44 children ages 7.99 to 16.89 years. Areal bone mineral density measurements were converted to z scores using both chronological and bone ages for each subject.
Areal bone mineral density z scores calculated using bone age, as opposed to chronological age, were significantly improved for both the total body and lumbar spine regions of interest. When subjects were grouped according to diagnosis, bone age generated z scores remained significantly improved for those with Crohn disease but not for those diagnosed with ulcerative colitis. Grouping of children with Crohn disease into younger and older ages produced significantly higher z scores using bone age compared with chronological for the older age group, but not the younger age group.
Our findings, in accordance with those presented in the literature, suggest that aBMD results in children with Crohn disease should include the consideration of bone age, rather than merely chronological age. Bone size, although not as easily available, would also be an important consideration for interpreting results in paediatric populations.
炎症性肠病患儿的骨矿物质密度临床结果通常使用按实足年龄的参考数据来报告。已知这些患儿，尤其是克罗恩病患儿，生长和成熟会延迟。因此，将临床结果与骨龄而非实足年龄进行比较更为合适。
使用双能X线吸收法测量面积骨矿物质密度（aBMD），并通过标准手部/腕部X线片采用坦纳 - 怀特豪斯3法评估骨龄。44名年龄在7.99至16.89岁的儿童有相关结果。对每个受试者，使用实足年龄和骨龄将面积骨矿物质密度测量值转换为z分数。
与使用实足年龄相比，使用骨龄计算的全身和腰椎感兴趣区域的面积骨矿物质密度z分数有显著改善。当根据诊断对受试者进行分组时，对于克罗恩病患者，使用骨龄生成的z分数仍有显著改善，但溃疡性结肠炎患者则不然。将克罗恩病患儿分为较年轻和较年长两组，与实足年龄相比，较年长组使用骨龄的z分数显著更高，但较年轻组并非如此。
我们的研究结果与文献中的结果一致，表明克罗恩病患儿的aBMD结果应考虑骨龄，而不仅仅是实足年龄。骨大小虽然不易获取，但在解释儿科人群的结果时也将是一个重要的考虑因素。
