UCL Great Ormond Street Institute of Child Health, University College London, London, U.K.
Institute of Epidemiology and Medical Biometry, Zentralinstitut für Biomedizinische Technik, Ulm University, Ulm, Germany.
Diabetes Care. 2018 Jun;41(6):1180-1187. doi: 10.2337/dc17-2271. Epub 2018 Apr 12.
International studies on childhood type 1 diabetes (T1D) have focused on whole-country mean HbA levels, thereby concealing potential variations within countries. We aimed to explore the variations in HbA across and within eight high-income countries to best inform international benchmarking and policy recommendations.
Data were collected between 2013 and 2014 from 64,666 children with T1D who were <18 years of age across 528 centers in Germany, Austria, England, Wales, U.S., Sweden, Denmark, and Norway. We used fixed- and random-effects models adjusted for age, sex, diabetes duration, and minority status to describe differences between center means and to calculate the proportion of total variation in HbA levels that is attributable to between-center differences (intraclass correlation [ICC]). We also explored the association between within-center variation and children's glycemic control.
Sweden had the lowest mean HbA (59 mmol/mol [7.6%]) and together with Norway and Denmark showed the lowest between-center variations (ICC ≤4%). Germany and Austria had the next lowest mean HbA (61-62 mmol/mol [7.7-7.8%]) but showed the largest center variations (ICC ∼15%). Centers in England, Wales, and the U.S. showed low-to-moderate variation around high mean values. In pooled analysis, differences between counties remained significant after adjustment for children characteristics and center effects ( value <0.001). Across all countries, children attending centers with more variable glycemic results had higher HbA levels (5.6 mmol/mol [0.5%] per 5 mmol/mol [0.5%] increase in center SD of HbA values of all children attending a specific center).
At similar average levels of HbA, countries display different levels of center variation. The distribution of glycemic achievement within countries should be considered in developing informed policies that drive quality improvement.
国际上针对儿童 1 型糖尿病（T1D）的研究主要集中在全国平均 HbA 水平上，从而掩盖了国家内部的潜在差异。我们旨在探索八个高收入国家之间和内部的 HbA 变化，以最好地为国际基准制定和政策建议提供信息。
本研究于 2013 年至 2014 年期间，从德国、奥地利、英国、威尔士、美国、瑞典、丹麦和挪威的 528 个中心，收集了 64666 名年龄<18 岁的 T1D 儿童的数据。我们使用固定和随机效应模型，根据年龄、性别、糖尿病病程和少数民族身份进行调整，以描述中心平均值之间的差异，并计算 HbA 水平总变异中归因于中心间差异的比例（组内相关系数 [ICC]）。我们还探讨了中心内变异与儿童血糖控制之间的关联。
瑞典的平均 HbA 最低（59mmol/mol [7.6%]），与挪威和丹麦一起，中心间差异最小（ICC≤4%）。德国和奥地利的平均 HbA 次之（61-62mmol/mol [7.7-7.8%]），但中心间差异最大（ICC~15%）。英格兰、威尔士和美国的中心显示出围绕高平均值的低到中等变异。在汇总分析中，调整儿童特征和中心效应后，国家间的差异仍然显著（ value <0.001）。在所有国家中，HbA 水平较高的儿童，其所在中心的血糖结果变化较大（HbA 值的中心标准差每增加 5mmol/mol [0.5%]，HbA 水平就会增加 5.6mmol/mol [0.5%]）。
在 HbA 平均水平相似的情况下，各国显示出不同的中心间变异水平。在制定推动质量改进的明智政策时，应考虑国家内部血糖控制的分布情况。
