Glucose series complexity at the threshold of diabetes 糖尿病阈值的血糖序列的复杂性

Background One of the earliest signs of dysfunction in a complex system is the simplification of its output. A well‐accepted method to measure this phenomenon is detrended fluctuation analysis (DFA). Herein, we evaluated the usefulness of DFA at the threshold of type 2 diabetes mellitus (T2DM). Methods We report on the clinical and glucometric characteristics of a sample of 103 patients at increased risk of developing T2DM. All patients had HbA1c levels 5%–6.4% and met at least one of the following criteria: body mass index (BMI) > 30 kg/m2, essential hypertension or a first‐degree relative with T2DM. For each patient, a 24‐h glucose time series was obtained, and the clinical and glucometric variables were compared. Results There was a significant correlation between the number of National Cholesterol Education Program – Adult Treatment Panel (ATP III) metabolic syndrome (MS)‐defining criteria and DFA (ρ = 0.231, P = 0.019), and DFA differed significantly between patients meeting or not the ATP III definition of MS (1.443 vs 1.399, respectively; P = 0.018). The DFA was not correlated with HbA1c. Depending on how it was calculated, the area under the log(Fn)∼log(n) curve correlated with HbA1c levels or the number of MS criteria. Conventional variability metrics (mean amplitude of glycemic excursions) did not differ between patients complying or not with the definition of MS. Conclusions Complexity analysis is capable of detecting differences in variables related to the risk of developing T2DM and could be a useful tool to study the initial phases of glucoregulatory dysfunction leading to T2DM. 摘要 背景：一个复杂的系统发生功能障碍的最早征象之一就是它的产出下降了。非趋势波动分析（detrended fluctuation analysis，DFA）是一种被广为接受的测量这一现象的方法。在这里，我们评估了DFA在2型糖尿病阈值中的实用性。 方法：我们研究的样本为103名可能发展为2型糖尿病的高风险患者，报告了他们的临床与血糖测量特征。所有患者的HbA1c水平为5%–6.4%并且符合下列标准中的至少一条：体重指数（BMI）>30 kg/m2、原发性高血压或者有1名一级亲属有2型糖尿病。测量每一名患者的24 h时间序列血糖值，比较他们的临床以及血糖测量值变量。 结果：全美胆固醇教育计划—成人治疗小组（ATP III）定义的代谢综合征的诊断标准的数量与DFA结果显著相关（ρ = 0.231，P = 0.019），符合或者不符合ATP III代谢综合征定义的患者之间的DFA结果有显著性差异（分别为1.443与1.399；P = 0.018）。DFA结果与HbA1c之间没有相关性。根据不同的计算方式，log(Fn)‐log(n)曲线下面积与HbA1c水平或MS诊断标准的数量相关。在符合或者不符合MS定义的患者之间常规的变异性指标（平均血糖波动幅度）没有差异。 结论：复杂性分析可以鉴别有可能导致2型糖尿病风险的各种变量之间的差异，对于研究导致2型糖尿病的早期相血糖调节功能障碍来说可能是一种有用的工具。