Have you recently had your blood drawn at your doctor’s office? Chances are, in addition to other studies, they checked a hematocrit level. A hematocrit level is a way of measuring what percentage of blood cells in your blood stream are red blood cells. In men, normal hematocrit values are between 43% and 54%, and in females a normal value is between 38% and 46%. When the hematocrit level is too low, it usually indicates anemia ‘” most commonly iron deficiency anemia. But, what if your doctor tells you that you have a high hematocrit count? What does this mean?
Dehydration
One of the most common causes of a high hematocrit count is simple dehydration. If you haven’t drunk enough fluids prior to getting your blood checked, your blood may be too concentrated which causes the hematocrit level to be elevated. This is usually not a serious condition and the hematocrit returns to normal once fluids are consumed.
Chronic Smoking
Are you a smoker? This could be another reason for a high hematocrit count. Chronic smoking leads to a lowered oxygen state which causes the body to produce more red blood cells to meet the oxygen demands of the body. The good news? When you quit smoking your hematocrit level returns to normal.
Living at High Altitudes
Do you live in the mountains? Living at a high elevation causes an increased hematocrit count because there are lower concentrations of oxygen in the air at high altitudes. As with smoking, the body compensates by pumping out more red blood cells to keep the body adequately oxygenated.
Chronic Lung Disease
Some chronic lung diseases such as emphysema are associated with a high hematocrit count. When the lungs are damaged and can’t take in as much oxygen, the kidneys produce a hormone called erythropoietin which increases red blood cell production to carry more oxygen to the body. Sleep apnea, a condition where breathing stops for short periods of time during sleep, can also cause hemoglobin levels to rise.
Medications
Some medications such as anabolic steroids used by athletes can cause a high hematocrit count. Some athletes want an increased hematocrit level since this means they have more red blood cells available to supply their muscles with oxygen during athletic events. To get their hematocrit level up, some athletes train at high altitudes or take anabolic steroids. Diuretics can also elevate hematocrit levels by promoting loss of fluid volume – causing red blood cells to be more concentrated.
Polcythemia vera
This is a rare blood disorder where the bone marrow produces too many red blood cells. People with this disease may also produce too many platelets which makes them more susceptible to blood clots.
Other Causes of a High Hematocrit Count
An increased hematocrit level can also be seen with certain types of heart disease and with kidney disease.
The Bottom Line?
If you have an elevated hematocrit count, it’s important to stop smoking and drink more fluids. Always consult with your doctor as more testing may need to be done to rule out other causes of a high hematocrit.
References:
Merck Manual. 18th Edition.
