Instable angina pectoris, heart failure NYHA class IV

Therapy with erythropoetin, melatonin and hypnotics

Acute renal failure or rapidly progressive glomerulonephritis

Bleeding or hemolysis as a cause of anemia

Deficiency of iron, folate and/or vitamin B12

Presence of chronic inflammatory disease or clinically significant infection

Hemoglobinopathies

Alcohol and/or drug abuse

Enrolment in another study

Any kind of disorder that compromises the ability of the subject to give written informed consent and/or to comply with study procedures

Circadian Rhythm of Erythropoietin And Melatonin in Renal Disease