Co-administration of POM3, atorvastatin improves lipid profiles
MedWire News: Research findings suggest that co-administering prescription omega-3-acid ethyl ester (POM3) and atorvastatin to patients with mixed dyslipidemia significantly lowers mean triglyceride-rich lipoprotein particles and remnants, while reducing very-low-density lipoprotein level-particle (VLDL-P) size.
Co-administration of POM3 with statins has been shown to significantly lower circulating triglyceride concentrations and reduce non-high-density lipoprotein (non-HDL) cholesterol. However, the effect of this combination therapy on lipoprotein particle sizes, concentrations, and compositions has been less well characterized.
To investigate the effects of combination therapy on lipoprotein particle concentrations and sizes, apolipoprotein (apo)CIII, and lipoprotein-associated phospholipase A2 mass, the researchers randomly assigned 237 patients with mixed dyslipidemia (non-HDL cholesterol over 160 mg/dL and triglyceride 250-599 mg/dL) to receive atorvastatin and POM3 or atorvastatin and placebo.
All patients underwent a 4-week Therapeutic Lifestyle Changes diet lead-in period, where they discontinued all statin medication. Atorvastatin was prescribed to all patients at doses of 10 mg/day for 8 weeks, followed by escalation to 20 mg/day for 4 weeks, and 40 mg/day for a further 4 weeks. Patients assigned to combination therapy also received 4 g/day POM3.
Compared with patients receiving atorvastatin only, those on combination therapy showed significantly greater reductions in VLDL-P size at 10, 20, and 40 mg/day atorvastatin (9.48, 9.89, and 9.98 nm vs 0.68, 2.35, and 2.17 nm, respectively) and concentration (56.9, 69.1, and 76.4 nmol/L vs 37.9, 45.0, and 51.7 nmol/L).
In addition, patients on combination therapy achieved greater increases in average LDL-P size (0.36, 0.45, and 0.52 nm vs 0.09, 0.12, and 0.19 nm) and large LDL-P concentration (31.7, 18.4, and 22.9 nmol/L vs -23.7, -28.9, and -36.8 nmol/L).
No significant change was seen in total LDL-P concentration and HDL-P size between the groups, although patients receiving combination therapy showed significantly greater increases in concentrations of large HDL-P (2.4, 2.7, and 2.7 µmol/L vs 1.1, 1.4, and 1.7 µmol/L) and decreases in medium HDL-P (3.2, 3.7, and 3.7 µmol/L vs 0.8, 1.3, and 2.0 µmol/L).
Significantly more patients receiving combination therapy (18.5%) switched from LDL subclass pattern B to pattern A than did those on atorvastatin alone (8.5%).
The study also found greater reductions in apoCIII and lipoprotein-associated phospholipase A2 levels among patients on the combination treatment.
"These findings may have important implications for understanding the influence of POM3 therapy on lipoprotein metabolism, although the clinical implications of the changes observed are uncertain at present," conclude the authors in the Journal of Clinical Lipidology.
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By Ingrid Grasmo