From the Guidelines
Increased hemoglobin levels can be caused by various factors, including dehydration, high altitude, polycythemia vera, chronic obstructive pulmonary disease, congenital heart disease, sleep apnea, certain medications like erythropoietin and testosterone replacement therapy, smoking, and kidney diseases. These conditions can stimulate the production of red blood cells, leading to elevated hemoglobin levels. According to a study published in the Mayo Clinic Proceedings 1, polycythemia vera is a bone marrow disorder that can cause excessive red blood cell production, leading to increased hemoglobin levels.
Living at high altitudes can also increase hemoglobin production as a natural adaptation to lower oxygen levels, with the increase in hemoglobin levels related to the degree of elevation, as shown in Table 9 of a study published in the American Journal of Kidney Diseases 1. Certain medications, such as erythropoietin and testosterone replacement therapy, can stimulate bone marrow to produce more red blood cells, leading to increased hemoglobin levels, as discussed in a study published in the New England Journal of Medicine 1.
Other factors, such as smoking, can also increase hemoglobin levels by reducing oxygen-carrying capacity and triggering compensatory hemoglobin production. Kidney diseases, particularly renal cell carcinoma, can increase hemoglobin through abnormal erythropoietin production. It is essential to consult a healthcare provider for proper diagnosis and treatment of the underlying cause if elevated hemoglobin is detected.
Some key points to consider include:
- Dehydration can concentrate hemoglobin due to reduced plasma volume
- High altitude increases hemoglobin production as a natural adaptation to lower oxygen levels
- Medical conditions like polycythemia vera, COPD, congenital heart disease, and sleep apnea can trigger increased red blood cell production in response to chronic hypoxia
- Certain medications like erythropoietin, anabolic steroids, and testosterone replacement therapy stimulate bone marrow to produce more red blood cells
- Smoking can increase hemoglobin levels by reducing oxygen-carrying capacity and triggering compensatory hemoglobin production
- Kidney diseases, particularly renal cell carcinoma, can increase hemoglobin through abnormal erythropoietin production.
From the Research
Causes of Increased Hemoglobin (Hb) Levels
- Polycythemia vera (PV), a myeloproliferative neoplasm characterized by an increased red blood cell mass and increased risk of thrombosis, can cause increased Hb levels 2
- Secondary causes of erythrocytosis, such as tobacco smoking or sleep apnea, can also lead to increased Hb levels 2
- Higher Hb levels within the normal variation can associate with key components of metabolic syndrome and total and cardiovascular mortality 3
- No direct evidence is available from studies 4, 5, and 6 to suggest a cause of increased Hb levels, as they focus on anemia diagnosis, polypectomy techniques, and preventing portal systemic encephalopathy, respectively
Associated Factors
- Age: being 60 years or older is a risk factor for thrombosis in patients with PV 2
- Prior thrombosis: increases the risk of thrombosis in patients with PV 2
- Extreme thrombocytosis (platelet count, ≥1000 × 109/L): can occur with acquired von Willebrand disease, which increases the bleeding risk in patients with PV 2
- Metabolic parameters: higher Hb levels associate positively with key anthropometric and metabolic parameters, such as leptin levels, adiponectin levels, and plasma ghrelin levels 3