Department of Public Health, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Nagoya, Japan.
Eur J Epidemiol. 2010 Mar;25(3):195-202. doi: 10.1007/s10654-009-9423-y.
Chronic and subclinical sympathetic over-activity may underlie development of type-2 diabetes mellitus (DM). Since longer heart rate-corrected QT interval (QTc) represents predominance of sympathetic activity within autonomic balance, we investigated influences of QTc on the incidence of DM in a follow-up study. The subjects were 12,530 men and 7,163 women aged 30-59 years and apparently healthy at baseline. QTc in resting ECG was obtained using Bazett's formula (QTcB), Fridericia's formula (QTcF) and the linear regression technique (QTcLR). Incident DM was identified by 'fasting serum glucose > or =7.00 mmol l(-1) (126 mg dl(-1))' or/and 'on medication for DM'. Using Cox proportional hazard models, hazard ratio (HR) for incident DM was estimated according to the quartiles (Q1-Q4) of QTcB, QTcF or QTcLR, and its linear trends across the quartiles were checked. Baseline age, BMI, smoking, drinking, exercise and education were computed as conventional confounders. During the follow-up of 93,337 person-years for men and 51,517 person-years for women, 637 men and 192 women developed DM. The multivariate-adjusted HRs(95% confidence interval) for Q4 of QTcB, QTcF and QTcLR against corresponding Q1 were 1.85(1.46, 2.34), 1.31(1.04, 1.65) and 1.58(1.26, 1.99), respectively, for men, and 2.03(1.31, 3.16), 1.34(0.91, 2.00) and 1.58(1.04, 2.38), respectively, for women. Both sexes showed increasing trends in the HRs across the quartiles of QTcB, QTcF and QTcLR. In conclusion, QTc in resting ECG moderately but proportionally predicts the risk for development of DM in middle-aged healthy men and women. Moreover, the adverse effects of prolonged QTc are independent of those of conventional risk factors.
慢性和亚临床交感神经活性过度可能是 2 型糖尿病（DM）发病的基础。由于校正后的 QT 间期（QTc）较长代表自主平衡中交感神经活动的优势，因此我们在一项随访研究中调查了 QTc 对 DM 发病率的影响。研究对象为 12530 名 30-59 岁男性和 7163 名女性，在基线时均无明显健康问题。静息心电图的 QTc 使用 Bazett 公式（QTcB）、Fridericia 公式（QTcF）和线性回归技术（QTcLR）获得。DM 的发病通过“空腹血糖>或=7.00mmol/L（126mg/dL）”或/和“正在服用 DM 药物”确定。使用 Cox 比例风险模型，根据 QTcB、QTcF 或 QTcLR 的四分位数（Q1-Q4）估计 DM 发病的风险比（HR），并检查四分位数之间的线性趋势。基线年龄、BMI、吸烟、饮酒、运动和教育被计算为常规混杂因素。在男性 93337 人年和女性 51517 人年的随访期间，男性有 637 人、女性有 192 人发生 DM。与相应 Q1 相比，男性 QTcB、QTcF 和 QTcLR 的 Q4 的多变量调整 HR（95%置信区间）分别为 1.85（1.46，2.34）、1.31（1.04，1.65）和 1.58（1.26，1.99），女性分别为 2.03（1.31，3.16）、1.34（0.91，2.00）和 1.58（1.04，2.38）。两性在 QTcB、QTcF 和 QTcLR 四分位数之间的 HR 均呈递增趋势。总之，静息 ECG 的 QTc 适度但成比例地预测了中年健康男性和女性发生 DM 的风险。此外，延长 QTc 的不良影响独立于传统危险因素的影响。
