The Effect of Omega-3 FA on Hypertriglyceridemia in Patients With T2DM(OCEAN)

In the present study, patients with type 2 diabetes and hypertriglyceride will be enrolled from multiple centers in China. Randomization was computer generated and stratified by center. After screening, eligible subjects will be randomly assigned into one of the following two groups: Omega-3 fatty acids capsules ( 2pills bid) and placebo capsules (2pills bid). Blood, feces and urine samples will be collected before and after treatment. Triglycerides (TG), total cholesterol (TC), LDL-C, HDL-C, HbA1C, fasting plasma glucose (FPG), postprandial plasma glucose (PPG) will be measured. Blood metabolomics profiles of lipids, amino acids, bile acids, the change of gut microbiota, and pharmacogenomic components and parameters will be evaluated too. Sample Size Calculation: The primary clinical endpoint involves comparing changes in triglyceride (TG) levels between the placebo group and the omega-3 treatment group after a 12-week intervention. According to literature reports \[Borthwick L J. The effects of an omega-3 ethyl ester concentrate on blood lipid concentrations in patients with hyperlipidaemia\[J\]. Clinical drug investigation, 1998, 15(5): 397-404\], following 12 weeks of n-3 or placebo-controlled treatment, patients with hypertriglyceridemia exhibited a 9.1±24.8% increase in the placebo group and a 28.3±19.1% decrease in the omega-3 treatment group (4g/day). Based on this data, we conservatively estimate no change in TG in the placebo group for this trial, while anticipating a 10% reduction in the omega-3 treatment group. With a combined standard deviation (SD) of 30%, α=0.05, β=0.2, we calculate the sample size based on the mean difference between the two groups, resulting in N1=N2=143 cases. Taking into account actual follow-up rates from preliminary research, we adjusted the estimated dropout rate from 20% to 5% and recalculated the sample size. Consequently, we plan to enroll 300 cases, with 150 in each of the omega-3 treatment and placebo groups, respectively.