Question: I recently had full bloods done and my doctor said they were all within the normal range, but that my red blood cells were a lot higher than the last time I had them done a couple of years ago. I am a woman in my late 40s. He suggested that I return to have them redone in six months. What does elevated red blood cells mean and how can I go about lowering them?
Dr Grant replies: To interpret your question properly, I need a few more details. Do you mean your ‘red blood cells’ have a high haemoglobin (oxygen-carrying red blood cell) count? Or simply high RBC (red blood cell) count but a haemoglobin within the range of normal? Secondly, what are the other measures of the red blood cells (MCV, HCT, MCH, MCHC) and what are your iron stores like such as ferritin, serum iron, transferrin saturation? Thirdly, are you having regular menstrual periods or do you have an IUD (intra-uterine device) for contraceptive reasons? Women who do not have regular periods may see their iron stores go higher than were previously noted on routine blood testing. Are you taking any iron supplements or multivitamins with low-dose iron? How much red meat do you eat on a weekly basis, and remember chicken and fish still contain about 70pc the amount of iron versus red meat. Lastly, is there a history of iron overload (haemochromatosis) in your family?
Ireland has the highest rate of the genetic condition called hereditary haemochromatosis (HH) in the world. Iron overload due to HH is when the body absorbs excess iron from food and deposits it in other tissues. Most commonly it can cause liver strain (even liver failure if not caught in a timely fashion) and diabetes when the iron deposits in the pancreas. Historically, this type of diabetes was known as bronze diabetes as the skin becomes tanned or bronze looking. However, when iron deposits in other tissues such as the heart, bones and joints, it can lead to heart failure, joint pain, fatigue, depression and loss of libido. These signs and symptoms often become apparent after 40 years of age.
The good news is that the diagnosis is relatively simple when two measures of iron stores are elevated in the blood, namely the ferritin and transferrin saturation, then blood samples are sent for genetic testing. Treatment is simply venesection (drawing a pint of blood) a couple of times per year. When iron stores are back to normal range, blood can be donated to the Irish Blood Transfusion Board. Moreover, there is no difference in mortality in patients with HH compared to the general population, once the diagnosis is made in a timely fashion and good compliance with treatment is maintained.
There should always be a certain level of caution involved when it comes to interpreting routine blood tests in a healthy individual without any signs or symptoms. The golden rule is always repeat the blood test because things often come back to normal. Unless the high ‘red blood cells’ are persistently high after repeat blood tests or getting worse, there is generally no cause for concern. On a practical level, you could consider reducing (or giving up) red meat (if applicable), reduce the portion size of chicken/fish and aim to drink two litres of water per day as these are seen as health-promoting behaviours.
Dr Jennifer Grant is a GP with Beacon HealthCheck