The overall goal of this study is to examine the role of fish oil supplementation in ameliorating the inflammatory state of uremia and the related muscle protein catabolism associated with this disease state. We hypothesize that if administered for a period of 3 months, fish oil will improve the chronic uremic inflammation. We further hypothesize that fish oil administration will improve the muscle protein breakdown associated with uremia and inflammation.

Inclusion Criteria:

• Patients on CHD for more than 6 months;
• Ability to read and sign the consent form;
• Have acceptable dialysis adequacy (Kt/V > 1.2);
• Use biocompatible hemodialysis membrane;
• Have a patent, well functioning, arteriovenous dialysis access or permanent dialysis catheter (no other option for arteriovenous access);
• Signs of chronic inflammation (average CRP of ≥ 5 mg/L for 3 consecutive measurements)

Exclusion Criteria:

• Pregnancy;
• Intolerance to the study medication;
• Severe, unstable, active, or chronic inflammatory disease (active infection, active connective tissue disorder, active cancer, HIV, liver disease);
• Diabetes mellitus on insulin therapy;
• Hospitalization within 1 month prior to the study;
• Malfunctioning arterial-venous vascular access (recirculation and/or blood flow < 500 ml/min);
• Patients receiving steroids (> 5 mg/day) and/or other immunosuppressive agents;
• Life-expectancy less than 6 months;
• Age less than 18 years old;
• Atrial fibrillation (only for those undergoing the optional Pulse Wave Velocity);
• Hypersensitivity to organic nitrates, isosorbide, or nitroglycerin (only for those undergoing the optional brachial artery Doppler).