EPO: The Blood Booster

Doping with EPO (Erythropoietin) seems to have begun in the 1980’s with competitive endurance athletes and The World Anti-Doping Agency (WADA) placed it on its list of banned substances in 1990. A reliable and valid detection test developed by French scientists was adopted and implemented in time for the 2000 Olympic Games. This performance enhancing substance has been linked to sudden deaths of athletes and many doping scandals over the years.

Erythropoietin is a naturally occurring hormone, which is produced by the kidneys. It stimulates the bone marrow to produce more red blood cells (RBC’s). This therefore increases the heamatocrit (non-liquid element of blood) and heamoglobin (oxygen carrying chemical) levels of blood. It was first developed as a drug to treat anemia, kidney failure and post-surgery blood loss. It can also be used to assist recovery from chemotherapy and deal with complications of HIV/Aids.

By raising the amount of red blood cells in the blood, the potential to transport oxygen around the body is increased. This improves energy production, especially through the aerobic/endurance energy system, which decreases the use of the anaerobic/short-term energy system, levels of lactate and fatigue. The marker for physical fitness / aerobic capacity, VO2 max, is then increased. Studies have shown time to fatigue/exhaustion (exercise tolerance) can be extended by up to 17% while taking EPO!

But it’s not all good. The increased heamatocrit/RBC levels causes hyperviscosity of the blood (excess density). Some side effects can include raised blood pressure, dehydration, nausea, lethargy, fever and seizures. This thicker blood can increase chance of heart attacks and stroke, as the cardiovascular system is overloaded. Often, once the drug is abused, the amount of RBC production that will actually take place becomes hard to predict, adding to the risks involved. In recent years, in addition to more extensive and accurate testing, some sporting codes have set up safety cut off levels of heamatocrit (50%), although this has been seen as unsuitable, as ‘normal’ levels of heamatocrit vary greatly from person to person.

The most well-known incident of EPO use in sport occurred around the 1998 Tour de France, when the Festina cycle team was found with large quantities of EPO and other banned substances during the 17th stage. Other high profile cases of EPO doping include two cross-country skiers at the 2002 Winter Olympics, an female Ironman World Champs silver medallist and a double cross-country world champion. Along with the laboratory manufactured versions of EPO, newer advanced bone marrow stimulating chemicals/drugs are being developed, such as CERA (Continuous Erythropoiesis Receptor Activator). This modern option for doping has a unique action on bone marrow that differs slightly to EPO and it’s effects can last longer inside the body. A test for CERA was a surprise addition to the 2008 Tour de France and later two-time stage winner Stefan Schumacher was found guilty of doping. In 2009 the International Olympic Committee (IOC) declared that it was to re-test blood and urine samples from the Beijing Summer Olympics for CERA and in November of last year, the Olympic 1500m champion Rashid Ramzi was stripped of his gold medal after testing positive.

Here’s a few links that you might find interesting:
WADA – http://www.wada-ama.org/en/
Doping Cases - http://en.wikipedia.org/wiki/List_of_doping_cases_in_sport

Jed