ABSTRACT: Background The American Heart Association recognizes high triglycerides as a cardiovascular risk factor. Methods and Results This retrospective observational administrative claims analysis (Optum Research Database) included statin-treated patients ?45 years old with diabetes mellitus and/or atherosclerotic cardiovascular disease, triglycerides 2.26 to 5.64 mmol/L, and a propensity-matched comparator cohort with triglycerides <1.69 mmol/L and high-density lipoprotein cholesterol >1.04 mmol/L. In the high-triglycerides cohort versus comparators (both n=10 990, 49% women), mean age was 61.7 versus 62.2 years and follow-up was 41.3 versus 42.1 months, respectively. Multivariate analysis of composite major cardiovascular events demonstrated significantly increased risk in the high-triglycerides (n=13 411 patients) versus comparator (n=32 506 patients) cohorts (hazard ratio [ HR ], 1.35; 95% confidence interval [ CI ], 1.225-1.485; P<0.001), with significantly higher risk for nonfatal myocardial infarction ( HR , 1.35; 95% CI , 1.19-1.52; P<0.001), nonfatal stroke ( HR , 1.27; 95% CI , 1.14-1.42; P<0.001), and need for coronary revascularization ( HR , 1.51; 95% CI , 1.34-1.69; P<0.001), but not unstable angina or cardiovascular death. Increased cardiovascular risk in the high-triglycerides versus comparator cohort was maintained, even with addition of non-high-density lipoprotein cholesterol to the multivariate model and when analyzing high and low high-density lipoprotein cholesterol subgroups. Average total healthcare cost per patient per month (cost ratio, 1.15; 95% CI , 1.084-1.210; P<0.001) and rate of occurrence of inpatient hospital stay ( HR , 1.17; 95% CI , 1.113-1.223; P<0.001) were also significantly greater in the high-triglycerides cohort. Conclusions In this real-world analysis, patients with high cardiovascular risk and high triglycerides had worse composite cardiovascular and health economic outcomes than patients with well-managed triglycerides and high-density lipoprotein cholesterol >1.04 mmol/L.