Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA.
Circ Arrhythm Electrophysiol. 2012 Aug 1;5(4):728-38. doi: 10.1161/CIRCEP.111.966259. Epub 2012 Jul 6.
Trans-fatty acid (TFA) consumption is associated with risk of coronary heart disease, and trans-18:2, but not trans-18:1, in red blood cell membranes has been associated with sudden cardiac arrest. Abnormal heart rate variability (HRV) reflects autonomic dysfunction and predicts cardiac death. Relationships between TFA consumption and HRV remain understudied. We determined whether total TFA consumption, as well as trans-18:1 and trans-18:2 TFA consumption, was independently associated with HRV in 2 independent cohorts in the United States and Portugal.
In 2 independent cohorts of older US adults (Cardiovascular Health Study [CHS], age 72±5 years, 1989/1995) and young Portuguese adults (Porto, age 19±2 years, 2008/2010), we assessed habitual TFA intake by food frequency questionnaires in CHS (separately estimating trans-18:1 and trans-18:2) and multiple 24-hour recalls in Porto (estimating total TFA only, which in a subset correlated with circulating trans-18:2 but not trans-18:1, suggesting that we captured the former). HRV was assessed using 24-hour Holters in CHS (n=1076) and repeated short-term (5-minute) ECGs in Porto (n=160). We used multivariate-adjusted linear regression to relate TFA consumption to HRV cross-sectionally (CHS, Porto) and longitudinally (CHS). In CHS, higher trans-18:2 consumption was associated with lower 24-hour SD of all normal-to-normal intervals both cross-sectionally (-12%; 95% CI, -19% to -6%; P=0.001) and longitudinally (-15%; 95% CI, -25% to -4%; P= 0.009) and lower 24-hour SD of 5-minute average N-N intervals and mean of the 5-minute SD of N-N intervals calculated over 24 hours (P<0.05 each). Higher trans-18:1 consumption in CHS was associated with more favorable 24-hour HRV in particular time-domain indices (24-hour SD of all normal-to-normal intervals, SD of 5-minute average N-N intervals, mean of the 5-minute SD of N-N intervals calculated over 24 hours; P<0.05 each). In Porto, each higher SD TFA consumption was associated with 4% lower 5-minute 24-hour SD of all normal-to-normal intervals (95% CI, -8% to -1%; P=0.04) and 7% lower 5-minute square root of the mean of the squares of successive N-N differences (95% CI, -13% to -1%; P=0.04).
Trans-18:2 consumption is associated with specific, less favorable indices of HRV in both older and young adults. Trans-18:1 consumption is associated with more favorable HRV indices in older adults. Our results support the need to investigate potential HRV-related mechanisms, whereby trans-18:2 may increase arrhythmic risk.
反式脂肪酸（TFA）的摄入与冠心病风险有关，而红细胞膜中的反式-18:2 与心源性猝死有关，却与反式-18:1 无关。心率变异性（HRV）的异常反映自主神经功能障碍，并预测心脏死亡。TFA 摄入与 HRV 之间的关系仍有待研究。我们在美国和葡萄牙的两个独立队列中确定了总 TFA 摄入，以及反式-18:1 和反式-18:2 TFA 摄入是否与 HRV 独立相关。
在两个独立的美国老年成年人队列（心血管健康研究[CHS]，年龄 72±5 岁，1989/1995 年）和年轻的葡萄牙成年人队列（波尔图，年龄 19±2 岁，2008/2010 年）中，我们使用 CHS 的食物频率问卷（分别估计反式-18:1 和反式-18:2）和波尔图的多次 24 小时回忆（仅估计总 TFA，在一个亚组中与循环反式-18:2 相关，但与反式-18:1 不相关，这表明我们捕获了前者）来评估习惯性 TFA 摄入。在 CHS 中使用 24 小时 Holters 评估 HRV（n=1076），在 Porto 中使用重复的短期（5 分钟）ECG 评估 HRV（n=160）。我们使用多元调整线性回归来横向（CHS、Porto）和纵向（CHS）比较 TFA 消耗与 HRV 的关系。在 CHS 中，较高的反式-18:2 消耗与 24 小时所有正常-正常间隔的 SD 呈负相关，无论是横向（-12%；95%CI，-19%至-6%；P=0.001）还是纵向（-15%；95%CI，-25%至-4%；P=0.009），与 24 小时 5 分钟平均 N-N 间隔的 SD 和 24 小时内计算的 N-N 间隔的 5 分钟 SD 的平均值呈负相关（P<0.05 各）。在 CHS 中，较高的反式-18:1 消耗与特定的更有利的 24 小时 HRV 时间域指数相关（24 小时所有正常-正常间隔的 SD、5 分钟平均 N-N 间隔的 SD、24 小时内计算的 N-N 间隔的 5 分钟 SD 的平均值；P<0.05 各）。在波尔图，每增加一个 SD 的 TFA 消耗与 5 分钟 24 小时所有正常-正常间隔的 SD 降低 4%相关（95%CI，-8%至-1%；P=0.04）和 5 分钟平方根的平均顺序 N-N 差异的平方降低 7%（95%CI，-13%至-1%；P=0.04）。
反式-18:2 消耗与老年人和年轻人的 HRV 特定、不太有利的指数有关。反式-18:1 消耗与老年人更有利的 HRV 指数有关。我们的研究结果支持需要研究潜在的与 HRV 相关的机制，其中反式-18:2 可能会增加心律失常风险。
