Comparison between Fasting and Non-Fasting Cut-Off Values of Triglyceride in Diagnosing High Triglyceride in Chinese Hypertensive Outpatients

Background: Hypertension (HBP) often occurs together with hypertriglyceridemia which indicates elevated triglyceride (TG) and remnant cholesterol (RC) levels. Non-fasting (i.e., postprandial) blood lipid test after a daily meal has been recommended by the European Atherosclerosis Society (EAS). However, little is known about the difference between fasting and non-fasting cut-off values in assessing high TG (HTG) and high RC (HRC) in HBP outpatients. Methods: 225 Chinese outpatients with HBP, including 119 fasting patients (i.e., fasting group) and 106 non-fasting patients (i.e., non-fasting group) were enrolled in this study. Non-fasting levels of blood lipids at 2 h after a daily breakfast were also tested in 33 patients among the fasting group. Venous blood samples were collected. Results: The non-fasting group had significantly higher levels of TG and RC while lower levels of total cholesterol, low-density lipoprotein cholesterol, and non-high-density lipoprotein cholesterol than the fasting group (p < 0.05). According to the TG and RC cut-off values of the EAS, the percentages of HTG and HRC in the non-fasting group were 72.6% and 70.8%, respectively, whereas those in the fasting group were 57.1% and 52.9%, respectively. According to the cut-off value of marked HTG commonly used in the Chinese population in clinical practice, the percentage of marked HTG in the non-fasting group was 57.5%, whereas that in the fasting group was 34.5%. However, the percentages of HTG (57.6% vs. 51.5%) and HRC (51.5% vs. 51.5%) marked HTG (30.3% vs. 33.3%) in the fasting state and at 2 h after a daily breakfast in 33 outpatients did not reach statistical significance. Conclusion: Non-fasting blood lipid tests could find more individuals with HTG as well as those with marked HTG among Chinese outpatients with HBP. It indicates that non-fasting blood lipid tests are worth being recommended in patients with HBP.