Effect of Coenzyme Q₁₀ on Biomarkers of Oxidative Stress and Cardiac Function in Hemodialysis Patients: The CoQ₁₀ Biomarker Trial

Background Oxidative stress is highly prevalent in patients with end-stage renal disease and is linked to excess cardiovascular risk. Identifying therapies that reduce oxidative stress has the potential to improve cardiovascular outcomes in patients undergoing maintenance dialysis. Study Design Placebo-controlled, 3-arm, double-blind, randomized, clinical trial. Setting & Participants 65 patients undergoing thrice-weekly maintenance hemodialysis. Intervention Patients were randomly assigned in a 1:1:1 ratio to receive once-daily coenzyme Q₁₀ (CoQ₁₀; 600 or 1,200 mg) or matching placebo for 4 months. Outcomes The primary outcome was plasma oxidative stress, defined as plasma concentration of F₂-isoprotanes. Secondary outcomes included levels of plasma isofurans, levels of cardiac biomarkers, predialysis blood pressure, and safety/tolerability. Measurements F₂-isoprostanes and isofurans were measured as plasma markers of oxidative stress, and N-terminal pro−brain natriuretic peptide and troponin T were measured as cardiac biomarkers at baseline and 1, 2, and 4 months. Results Of 80 randomly assigned patients, 15 were excluded due to not completing at least 1 postbaseline study visit and 65 were included in the primary intention-to-treat analysis. No treatment-related major adverse events occurred. Daily treatment with 1,200 mg, but not 600 mg, of CoQ₁₀ significantly reduced plasma F₂-isoprostanes concentrations at 4 months compared to placebo (adjusted mean changes of −10.7 [95% CI, −7.1 to −14.3] pg/mL [P < 0.001] and −8.3 [95% CI, −5.5 to −11.0] pg/mL [P = 0.1], respectively). There were no significant effects of CoQ₁₀ treatment on levels of plasma isofurans, cardiac biomarkers, or predialysis blood pressures. Limitations Study not powered to detect small treatment effects; difference in baseline characteristics among randomized groups. Conclusions In patients undergoing maintenance hemodialysis, daily supplementation with 1,200 mg of CoQ₁₀ is safe and results in a reduction in plasma concentrations of F₂-isoprostanes, a marker of oxidative stress. Future studies are needed to determine whether CoQ₁₀ supplementation improves clinical outcomes for patients undergoing maintenance hemodialysis.