Department of Anesthesiology and Resuscitology, Okayama University Hospital, Okayama, Japan.
Crit Care Med. 2011 Jan;39(1):105-11. doi: 10.1097/CCM.0b013e3181feb5ea.
The relationship between hyperglycemia and mortality is altered by the presence of diabetes mellitus. Biological adjustment to preexisting hyperglycemia might explain this phenomenon. We tested whether the degree of preexisting hyperglycemia would modulate the association between glycemia and outcome during critical illness in patients with diabetes mellitus.
Retrospective observational study.
Two tertiary intensive care units.
Four hundred fifteen critically ill diabetic patients with HbA1c levels measured within 3 months of intensive care unit admission.
None.
There were 9,946 blood glucose measurements in this study cohort (glucose measured 6.7 times per day; every 3.6 hrs on average). The median preadmission HbA1c level was 7.0%. There was no significant difference in HbA1c levels (p = .17) or time-weighted average of blood glucose concentrations (p = .49) between survivors and nonsurvivors. The time-weighted average of blood glucose concentrations during intensive care unit stay for nonsurvivors was lower than that of survivors when the HbA1c was >6.8%. In multivariate analysis, we found that there was a significant interaction between HbA1c and the time-weighted glucose level, indicating that the relationship between HbA1c and mortality changed according to the levels of time-weighted average of blood glucose concentrations (p = .008). As a consequence, in patients with higher (>7%) preadmission levels of HbA1c, the higher the time-weighted acute glucose concentration during intensive care unit stay (>10 mmol/L), the lower the hospital mortality compared with the lower HbA1c cohort (<7%).
In patients with diabetes mellitus admitted to intensive care units, there was a significant interaction between preexisting hyperglycemia and the association between acute glycemia and mortality. These observations generate the hypothesis that glucose levels that are considered safe and desirable in other patients might be undesirable in diabetic patients with chronic hyperglycemia. Further studies are required to confirm or refute our findings.
高血糖与死亡率之间的关系因糖尿病的存在而改变。对预先存在的高血糖的生物学调整可能解释了这一现象。我们测试了预先存在的高血糖程度是否会调节糖尿病患者在重症监护期间血糖与结局之间的关系。
回顾性观察性研究。
两个三级重症监护病房。
415 名重症监护病房内 HbA1c 水平在 3 个月内接受测量的糖尿病患者。
无。
本研究队列中有 9946 次血糖测量（每天测量 6.7 次；平均每 3.6 小时一次）。入院前的中位 HbA1c 水平为 7.0%。幸存者和非幸存者之间的 HbA1c 水平（p =.17）或血糖浓度的时间加权平均值（p =.49）无显著差异。非幸存者的重症监护期间的血糖浓度时间加权平均值低于幸存者时，HbA1c ＞ 6.8%。在多变量分析中，我们发现 HbA1c 与血糖时间加权平均值之间存在显著的交互作用，表明 HbA1c 与死亡率之间的关系根据血糖时间加权平均值的水平而变化（p =.008）。因此，在入院前 HbA1c 水平较高（＞7%）的患者中，重症监护期间血糖时间加权急性浓度越高（＞10mmol/L），与 HbA1c 较低的队列（＜7%）相比，医院死亡率越低。
在入住重症监护病房的糖尿病患者中，预先存在的高血糖与急性血糖和死亡率之间的关联存在显著的交互作用。这些观察结果产生了这样一种假设，即对于其他患者而言，认为安全和理想的血糖水平在患有慢性高血糖的糖尿病患者中可能是不理想的。需要进一步的研究来证实或反驳我们的发现。
