Reasons for elevated red blood cell count?

Below: Your body may increase red blood cell production to compensate for any condition that results in low oxygen levels, including: •Congenital heart disease in adults •Heart failure •A condition present at birth that reduces the oxygen-carrying capacity of red blood cells (hemoglobinopathy) •High altitudes •COPD (chronic obstructive pulmonary disease) and other lung diseases •Pulmonary fibrosis •Sleep apnea •Nicotine dependence (smoking) Performance-enhancing drugs Certain drugs stimulate the production of red blood cells, including: •Anabolic steroids •Blood doping (transfusion) •Injections of a protein (erythropoietin) that enhances red blood cell production Increased red blood cell concentration •Dehydration (If the liquid component of the blood (plasma) is decreased, as in dehydration, the red blood cell count increases. This is due to the red blood cells becoming more concentrated. The actual number of red blood cells stays the same.) Kidney disease Rarely, in some kidney cancers and sometimes after kidney transplants, the kidneys might produce too much erythropoietin. This enhances red blood cell production. Bone marrow overproduction •Polycythemia vera •Other myeloproliferative disorders