National Institute for Health and Welfare, Department of Chronic Disease Prevention, Helsinki, Finland.
BMC Med Res Methodol. 2011 May 10;11:63. doi: 10.1186/1471-2288-11-63.
For practical reasons it is not easy to obtain fasting samples in large population health surveys. Non-fasting triglyceride (Tg) values are difficult to interpret. The authors compared the accuracy of statistically corrected non-fasting Tg values with true fasting values and estimated the misclassification of subjects with high low-density lipoprotein cholesterol (LDL-C) and the metabolic syndrome.
Non-fasting blood was obtained from a population-based sample of 4282 individuals aged 24-75 years in the National FINRISK 2007 Study. Fasting blood samples were drawn from the same persons 3 months later. Non-fasting serum Tg values were converted into fasting values using previously published formula. LDL-C was calculated and classification of the metabolic syndrome was carried out according to three different latest guidelines.
The median (25th, 75th percentile) non-fasting serum Tg concentration was 1.18 (0.87, 1.72) mmol/L and after postprandial correction 1.06 (0.78, 1.52) mmol/L. The true-fasting serum Tg concentration was 1.00 (0.75, 1.38) mmol/L (P < 0.001) vs. non-fasting and corrected value. Bias of the corrected value was +5.9% compared with the true-fasting Tg. Of the true fasting subjects, 56.4% had LDL-C ≥ 3.00 mmol/L. When calculated using non-fasting serum Tg, the prevalence of high LDL-C was 51.3% and using statistically corrected Tg it was 54.8%. The prevalence of metabolic syndrome was 35.5% among fully fasted persons and among non-fasting subjects 39.7%, which after statistical correction of Tg decreased to 37.6% (P < 0.001 for all comparisons).
Correction of non-fasting serum Tg to fasting values plays a minor role in population studies but nevertheless reduces misclassification of calculated high LDL-C from 5.1 to 1.6% and the metabolic syndrome from 4.2 to 2.1%.
由于实际原因，在大型人群健康调查中很难获得空腹样本。非空腹甘油三酯（Tg）值难以解释。作者比较了统计学校正的非空腹 Tg 值与真实空腹值的准确性，并估计了高低密度脂蛋白胆固醇（LDL-C）和代谢综合征患者的分类错误。
从全国 FINRISK 2007 研究中 24-75 岁的人群基础样本中采集非空腹血样。3 个月后从同一人身上抽取空腹血样。使用先前发表的公式将非空腹血清 Tg 值转换为空腹值。计算 LDL-C，并根据三种最新指南进行代谢综合征的分类。
中位数（25%，75%）非空腹血清 Tg 浓度为 1.18（0.87，1.72）mmol/L，餐后校正后为 1.06（0.78，1.52）mmol/L。真实空腹血清 Tg 浓度为 1.00（0.75，1.38）mmol/L（P <0.001），与非空腹和校正值相比。校正值与真实空腹 Tg 的偏差为+5.9%。在真正空腹的受试者中，56.4%的 LDL-C≥3.00mmol/L。使用非空腹血清 Tg 计算时，高 LDL-C 的患病率为 51.3%，使用统计学校正的 Tg 时为 54.8%。在完全禁食的人群中，代谢综合征的患病率为 35.5%，而在非禁食人群中为 39.7%，在 Tg 进行统计学校正后，这一比例下降至 37.6%（所有比较均 P<0.001）。
将非空腹血清 Tg 校正为空腹值在人群研究中作用不大，但仍能将计算出的高 LDL-C 的错误分类从 5.1%减少到 1.6%，将代谢综合征的错误分类从 4.2%减少到 2.1%。
