Lower triglyceride levels are associated with better endothelial function.

• FMD values were highest in the group with extremely low levels of triglycerides. • Lower triglyceride levels are associated with better endothelial function. • The group with extremely low triglycerides had fewer atherosclerosis risk factors. • The odds ratio for a lower quartile of FMD remained independently lower. Increased serum triglyceride levels are independently associated with endothelial dysfunction. However, there is little evidence to define normal levels of triglycerides and there is little information on endothelial function in subjects with extremely low levels of triglycerides. The purpose of this study was to determine the relationship between triglycerides, especially low levels of triglycerides, and vascular function. We measured flow-mediated vasodilation (FMD) in 7047 subjects and nitroglycerine-induced vasodilation (NID) in 1017 subjects. We divided the subjects into eight groups by triglyceride levels: <50 mg/dL, 50-69 mg/dL, 70-89 mg/dL, 90-109 mg/dL, 110-129 mg/dL, 130-149 mg/dL, 150-199 mg/dL, and ≥200 mg/dL. FMD was significantly higher in subjects with triglyceride levels of <50 mg/dL than in subjects with triglyceride levels of 50-69 mg/dL, 70-89 mg/dL, 90-109 mg/dL, 110-129 mg/dL, 130-149 mg/dL, 150-199 mg/dL, and ≥200 mg/dL (p =0.002, p <0.001, p <0.001, p <0.001, p<0.001, p<0.001, and p <0.001, respectively). Using triglyceride levels of >200 mg/dL as a reference, the odds ratios for a lower quartile of FMD were significantly lower in the <50 mg/dL group, 50-69 mg/dL group, 70-89 mg/dL group, and 90-109 mg/dL group after adjustment for age, gender and other cardiovascular risk factors. There was a slight negative correlation between NID and triglycerides (r =-0.074; p =0.019). However, there was no significant differences in NID among the eight groups. FMD values were highest in subjects with extremely low levels of triglycerides (<50 mg/dL). Lower triglyceride levels were associated with better endothelial function. http://www.umin.ac.jp (University Hospital Medical Information Network Clinical Trials Registry) (UMIN000012950) [ABSTRACT FROM AUTHOR]