University of Washington School of Medicine, Seattle, WA
Diabetes Care. 2015 Aug;38(8):1610-4. doi: 10.2337/dc14-2898.
There is no argument that improving mean levels of glycemic control as judged by assays for glycated hemoglobin (HbA(1c)) reduces the risks of microvascular complications and cardiovascular disease events in patients with type 1 and type 2 diabetes. However, observations in some trials have suggested that targeting HbA(1c) to suggested targets may not always result in improved outcomes for people with long-standing type 2 diabetes. The reasons why the glycemic control strategies that primarily use HbA(1c) in these studies did not have predicted outcomes are not clear. Thus, controversy remains as to whether there are glycemic metrics beyond HbA(1c) that can be defined as effective measures that can be used in addition to HbA(1c) to help in assessing the risk of an individual developing diabetes complications. In this regard, the concept of "glycemic variability" (GV) is one metric that has attracted a lot of attention. GV can be simply defined as the degree to which a patient's blood glucose level fluctuates between high (peaks) and low (nadir) levels. The best and most precise way to assess GV is also one that is still debated. Thus, while there is universal agreement that HbA(1c) is the current gold standard for the primary clinical target, there is no consensus as to whether other proposed glycemic metrics hold promise to provide additional clinical data or whether there should be additional targets beyond HbA(1c). Therefore, given the current controversy, we provide a Point-Counterpoint debate on this issue. In the point narrative below, Dr. Hirsch provides his argument that fluctuations in blood glucose as assessed by GV metrics are deleterious and control of GV should be a primary treatment target. In the following counterpoint narrative, Dr. Bergenstal argues that there are better markers to assess the risk of diabetes than GV and provides his consideration of other concepts.
毫无疑问,糖化血红蛋白(HbA1c)检测结果显示的血糖平均水平得到改善,可以降低 1 型和 2 型糖尿病患者微血管并发症和心血管疾病事件的风险。然而,一些试验的观察结果表明,将 HbA1c 靶向设定为建议目标,并不总是能为长期患有 2 型糖尿病的患者带来更好的结果。这些研究中主要使用 HbA1c 的血糖控制策略为何未能达到预期结果的原因尚不清楚。因此,是否存在除 HbA1c 之外的血糖指标,可以被定义为有效措施,除了 HbA1c 之外还可以用于评估个体发生糖尿病并发症的风险,仍然存在争议。在这方面,“血糖变异性”(GV)的概念是一个引起广泛关注的指标。GV 可以简单地定义为患者的血糖水平在高(峰值)和低(谷值)之间波动的程度。评估 GV 的最佳和最精确方法也仍有争议。因此,虽然普遍认为 HbA1c 是当前主要临床目标的金标准,但对于其他拟议的血糖指标是否有希望提供额外的临床数据,或者除了 HbA1c 之外是否应该有其他目标,尚无共识。因此,鉴于目前的争议,我们就这个问题进行了一场观点对立的辩论。在下面的观点叙述中,Hirsch 博士提出了他的论点,即通过 GV 指标评估的血糖波动是有害的,控制 GV 应该是主要的治疗目标。在接下来的反驳观点中,Bergenstal 博士认为,有比 GV 更好的指标来评估糖尿病风险,并提供了他对其他概念的考虑。