College of Pharmacy, Sookmyung Women's University, Seoul, Korea.
Department of Biostatistics, Clinical Research Coordinating Center, Catholic Medical Center, The Catholic University of Korea, Seoul, Korea.
J Korean Med Sci. 2023 Jan 30;38(4):e24. doi: 10.3346/jkms.2023.38.e24.
It remains unclear whether a combination of glycemic variability and glycated hemoglobin (HbA1c) status leads to a higher incidence of cardiovascular disease (CVD). Therefore, to investigate CVD risk according to the glucose control status during early diabetes, we examined visit-to-visit HbA1c variability among patients with type 2 diabetes (T2DM).
In this 9-year retrospective study, we measured HbA1c levels at each visit and tracked the change in HbA1c levels for 3 years after the first presentation (observation window) in newly diagnosed T2DM patients. We later assessed the occurrence of CVD in the last 3 years (target outcome window) of the study period after allowing a 3-year buffering window. The HbA1c variability score (HVS; divided into quartiles, HVS_Q1-4) was used to determine visit-to-visit HbA1c variability.
Among 4,817 enrolled T2DM patients, the mean HbA1c level was < 7% for the first 3 years. The group with the lowest HVS had the lowest rate of CVD (9.4%; 104/1,109 patients). The highest incidence of CVD of 26.7% (8/30 patients) was found in HVS [≥ 9.0%]_Q3, which was significantly higher than that in HVS [6.0-6.9%]_Q1 ( = 0.006), HVS [6.0-6.9%]_Q2 ( = 0.013), HVS [6.0-6.9%]_Q3 ( = 0.018), and HVS [7.0-7.9%]_Q3 ( = 0.040).
To our knowledge, this is the first long-term study to analyze the importance of both HbA1c change and visit-to-visit HbA1c variability during outpatient visits within the first 3 years. Lowering glucose levels during early diabetes may be more critical than reducing visit-to-visit HbA1c variability.
目前尚不清楚血糖变异性和糖化血红蛋白（HbA1c）状态的结合是否会导致更高的心血管疾病（CVD）发生率。因此，为了研究早期糖尿病期间血糖控制状态下的 CVD 风险，我们检查了 2 型糖尿病（T2DM）患者的随访间 HbA1c 变异性。
在这项 9 年的回顾性研究中，我们测量了每位患者就诊时的 HbA1c 水平，并在首次就诊后 3 年内跟踪 HbA1c 水平的变化（观察窗口）。在研究期间的最后 3 年（目标结局窗口），我们允许 3 年缓冲窗口后，评估 CVD 的发生情况。使用 HbA1c 变异分数（HVS；分为四分位，HVS_Q1-4）来确定随访间 HbA1c 变异性。
在纳入的 4817 例 T2DM 患者中，前 3 年的平均 HbA1c 水平<7%。HVS 最低的组 CVD 发生率最低（9.4%；104/1109 例）。HVS[≥9.0%]_Q3 的 CVD 发生率最高（26.7%，8/30 例），明显高于 HVS[6.0-6.9%]_Q1（=0.006）、HVS[6.0-6.9%]_Q2（=0.013）、HVS[6.0-6.9%]_Q3（=0.018）和 HVS[7.0-7.9%]_Q3（=0.040）。
据我们所知，这是第一项分析早期糖尿病门诊随访期间 HbA1c 变化和随访间 HbA1c 变异性重要性的长期研究。降低早期糖尿病期间的血糖水平可能比降低随访间 HbA1c 变异性更为关键。
