Nathan D M, Turgeon H, Regan S
Diabetes Center, Department of Biostatistics, Massachusetts General Hospital, 50 Staniford Street, Suite 340, Boston, MA 02114, USA.
Diabetologia. 2007 Nov;50(11):2239-44. doi: 10.1007/s00125-007-0803-0. Epub 2007 Sep 13.
AIMS/HYPOTHESIS: HbA(1c), expressed as the percentage of adult haemoglobin that is glycated, is the most widely used measure of chronic glycaemia. Achieving near-normal HbA(1c) levels has been shown to reduce long-term complications and the HbA(1c) assay is recommended to determine whether treatment is adequate and to guide adjustments. However, daily adjustments of therapy are guided by capillary glucose levels (mmol/l). We determined the relationship between an accurate measure of mean glucose levels over time and the HbA(1c) level, and whether HbA(1c) can be expressed in the same units as self-monitoring results.
Twenty-two participants with diabetes and three non-diabetic participants were included in this longitudinal observational study. Mean glucose levels were measured by continuous glucose monitoring (CGM), which measures interstitial glucose levels every 5 min, for 12 weeks. Capillary measurements were obtained four times per day to confirm the accuracy of CGM. HbA(1c) was measured at baseline and every 4 weeks.
The HbA(1c) results at weeks 8 and 12 correlated strongly (r = 0.90) with the CGM results during the preceding 8 and 12 weeks. A curvilinear (exponential) relationship and a linear regression captured the relationship with similarly high correlations, which allowed transformation of HbA(1c) values to a calculated mean glucose level.
HbA(1c) correlates closely with a complete measure of average glycaemia over the preceding 8-12 weeks. The translation of HbA(1c) to an average glucose level for reporting and management purposes is feasible.
目的/假设：糖化血红蛋白（HbA₁c）以糖化成人血红蛋白的百分比表示，是最广泛使用的慢性血糖测量指标。已证明将HbA₁c水平控制在接近正常水平可减少长期并发症，因此建议使用HbA₁c检测来确定治疗是否充分并指导调整治疗方案。然而，日常治疗调整是根据毛细血管血糖水平（毫摩尔/升）进行指导的。我们确定了一段时间内平均血糖水平的准确测量值与HbA₁c水平之间的关系，以及HbA₁c是否可以用与自我监测结果相同的单位表示。
本纵向观察性研究纳入了22名糖尿病患者和3名非糖尿病患者。通过连续血糖监测（CGM）测量平均血糖水平，该监测每5分钟测量一次组织间液葡萄糖水平，持续12周。每天进行4次毛细血管测量以确认CGM的准确性。在基线和每4周测量一次HbA₁c。
第8周和第12周的HbA₁c结果与前8周和12周的CGM结果密切相关（r = 0.90）。曲线（指数）关系和线性回归以相似的高相关性描述了这种关系，这使得可以将HbA₁c值转换为计算出的平均血糖水平。
HbA₁c与前8 - 12周的平均血糖完整测量值密切相关。为了报告和管理目的，将HbA₁c转换为平均血糖水平是可行的。
