The results of the Hgb blood test can help your doctor determine if further testing is needed, or help to make treatment decisions. High hemoglobin levels can be due to lung disease, dehydration, or excess red blood cell production. Low hemoglobin levels can be the result of a number of medical conditions including iron deficiency, sickle cell anemia, cirrhosis of the liver, kidney disease, and cancers that affect the body's bone marrow.
There are some things that can affect the results of the test. The time of the test can affect your result, as hemoglobin levels are at their highest in the morning. Smokers are also known to have higher levels of hemoglobin than those who do not smoke. Other factors that can affect the results of this test include age, gender, and altitude of where a patient lives.