EPA versus DHA fish oil: effects on blood clotting and cholesterol

Differential Thrombogenesis Effects of Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) Mediated by High-Density Lipoprotein (HDL)

This study will test whether taking four grams a day of either EPA or DHA fish oil for eight weeks changes blood lipids and clotting markers in adults with high triglycerides and low HDL.

Quick facts

• Phase: EARLY_PHASE1
• Study type: Interventional
• Enrollment: 80 (estimated)
• Ages: 18 Years to 69 Years
• Sex: All
• Sponsor: The Miriam Hospital (other)
• Locations: 1 site (Providence, Rhode Island)
• Trial ID: NCT06494488 on ClinicalTrials.gov

What this trial studies

Researchers will randomize adults with atherogenic dyslipidemia to receive 4 grams per day of either EPA or DHA for eight weeks and collect blood and urine samples at baseline and after supplementation. The study includes three clinic visits, laboratory tests of lipids, thromboelastography, urinary thromboxane metabolites, platelet aggregation studies, and flow cytometry of platelets and platelet-leukocyte aggregates. Participants will keep a 28-day food and activity log and must limit high-fish intake during the study. The goal is a controlled, head-to-head comparison of the biological and safety effects of EPA versus DHA in a hyperlipidemic population.

Who should consider this trial

Good fit: Adults with fasting triglycerides 150–499 mg/dL, low HDL (≤40 mg/dL men, ≤50 mg/dL women), LDL between 41–130 mg/dL, able to consent, and willing to limit fatty fish intake are ideal candidates.

Not a fit: People with normal triglycerides/HDL, current smokers, pregnant or breastfeeding individuals, those taking anticoagulants/aspirin/NSAIDs, or those with significant liver, kidney, or thyroid dysfunction are unlikely to benefit or be eligible.

Why it matters

Potential benefit: If successful, the trial could identify which omega-3 (EPA or DHA) more favorably affects clotting and lipid markers, helping guide safer and more effective supplement choices for people with atherogenic dyslipidemia.

How similar studies have performed: Previous large trials showed cardiovascular benefit with EPA-only regimens but not with mixed EPA/DHA products, and no prior head-to-head clinical comparison of EPA versus DHA in hyperlipidemic patients has been reported.

Eligibility criteria

Inclusion Criteria:

* Fasting TG levels ≥ 150 mg/dL and \< 500 mg/dL and HDL-C ≤ 40 (men) or ≤ 50 (women)
* LDL-C \> 40 mg/dL and ≤ 130 mg/dL
* Able to provide informed consent and adhere to study schedules
* Agree to follow and maintain a relatively stable and low fatty fish intake diet (\<3 servings per week)

Exclusion Criteria:

* Female with pregnancy, planned pregnancy (within the study period), or currently breastfeeding.
* Subjects with weight changes greater than 20% over the past 3 months
* Subjects planning a significant change in diet or exercise levels
* Malabsorption syndrome and/or chronic diarrhea
* Use of dietary supplements containing n-3 PUFA fatty acids
* Frequent consumption of n-3 PUFA-enriched fish (\>3 times a week)
* Abnormal liver, kidney, or thyroid functions
* Drug or alcohol abuse within 6 months or significant mental/psychological impairment
* Current smokers
* Subjects taking daily aspirin, NSAIDs, anticoagulant, or corticosteroids
* Subjects with known bleeding disorders (for example, hemophilia)
* Known sensitivity or allergy to fish, shellfish, or omega-3 fatty acid supplements
* Subjects requiring regular transfusions for any reason
* No ethnic/racial groups will be excluded

Where this trial is running

Providence, Rhode Island

• Brown University Health - Lipid Clinic — Providence, Rhode Island, United States (RECRUITING)

Study contacts

• Principal investigator: Wenliang Song, MD — LIFESPAN CARDIOVASCULAR INSTITUTE
• Study coordinator: Wenliang Song, MD

Conditions: Lipid Metabolism Disorders, Hypertriglyceridemia, Fish oil, Atherogenic lipidemia, Lipoproteins