Industry News: Everything You Need To Know About Blood Doping
Doping in sports and athletic competitions has become increasingly popular, particularly in endurance and elite events. These sports require high levels of speed, longer endurance, and increased aerobic activities to ensure optimum performance. To a competitor, a split second spells the difference between a gold and a silver medal. In efforts to guarantee victory and to continue the winning streak, some athletes resort to blood doping methods to gain an advantage over their opponents.
What is Blood Doping?
Blood doping refers to the use of illicit products and methods designed to improve athletic performance by artificially enhancing the process of transporting oxygen from the blood to the skeletal muscles. The rate at which oxygen is carried to the muscles depends on factors such as cardiac output, oxygen extraction, and hemoglobin mass. Blood doping manipulates cardiac output during competitions by increasing the oxygen content in the artery and by elevating the levels of hemoglobin in the bloodstream. Hemoglobin is the protein that carries the oxygen throughout the body. Thus, by increasing the volume of hemoglobin concentrations, more oxygen reaches the athlete’s muscles to improve his athletic performance and endurance. Blood doping is listed among the Prohibited Substances and Methods prescribed by the World Anti-Doping Agency (WADA).
It is likewise banned by the International Olympic Committee (IOC) and other international sports organizations and federations. The use of blood doping along with the intake of pharmaceutical performance enhancement substances is common among endurance athletes including distance runners, cross-country skiers, and cyclists.
Types of Blood Doping
There are three widely used types of blood doping. They are:
Blood transfusions are typically done to replace blood that was lost due to injury, accidents, or surgical procedures. Transfusions are also administered to patients who suffer from low red blood cell counts caused by conditions such as anemia or kidney failure. Athletes utilize the procedure in two ways: Autologous transfusion In autologous transfusions, the athlete authorizes the withdrawal of 1 to 4 units of blood (1 unit = 450 ml) several weeks prior to the competition. The blood is centrifuged and frozen at -80°C. Between 1 to 7 days before the high-endurance event, the blood is thawed and re-infused back to the donor. Approximately 50 percent of the stored blood is discarded for safety reasons. Homologous transfusion In homologous transfusion, the blood donor is different from the recipient. Blood is taken from someone else who has the same blood type as the athlete involved. The procedure undertaken is the same as autologous transfusion.
Injections of Erythropoietin (EPO)
EPO is a peptide hormone that is naturally produced by the interstitial fibroblasts in the kidneys. It is released to act on the bone marrow to stimulate red blood cell production. An increase in the number of red blood cells allows the blood to have a greater capacity to carry oxygen throughout the body. Medically, EPO was developed to help cancer patients recover from the effects of chemotherapy and radiation. EPO injections are also administered to those suffering from anemia and kidney diseases. Athletes, however, resort to injecting EPO in order to increase the production of red blood cells, stimulate aerobic performance, and enhance endurance.
Injections of synthetic oxygen carriers
The third method of blood doping involves the use of artificial oxygen carriers. There are two popular types:
Hemoglobin-based oxygen carriers (HBOCs)
HBOCs are either molecularly engineered human or animal hemoglobins that are optimized to deliver oxygen and improve intravascular circulation. Injecting HBOCs are beneficial to athletes because it has the effect of increasing exercise capacity.
PFCs or fluorocarbons refer to water-soluble, synthetic compounds that consist of carbon and fluorine atoms bonded together in strong C-F bonds. PFCs act as blood substitutes that dissolve oxygen in order increase the amount of oxygen delivered to the tissues. Because PFCs are small in size, they are able to pervade even the tiniest capillaries to increase the efficiency of oxygen delivery. In the medical practice, synthetic oxygen carriers are used in emergency cases when blood supply is not immediately available or when there is a potential risk of blood infection. Athletes misuse or abuse the use artificial oxygen carriers to achieve the same performance-enhancing effects as other blood doping methods.
Health Risks and Side Effects
Blood doping methods are associated with several health risks. The common side effects of these methods include the following:
- Increased blood viscosity
- Formation of blood clots
- Cardiovascular diseases including myocardial infarction
- Pulmonary embolism
- Cerebral embolism
- Cerebrovascular accident or stroke
- Allergic reactions that can produce fever and shock
- Kidney damage
- Lung and liver toxicity
- Iron overload
- Flu-like symptoms
Homologous transfusions place the athletes at an increased risk of developing allergic reactions and contracting blood-borne diseases such as Hepatitis B, Hepatitis C, and HIV. Injecting synthetic oxygen carriers can produce side effects that include the following:
- Flu-like symptoms;
- Hepatic engorgement
- Organ failure
- Impaired immune defense mechanisms
- Increased body temperature
Detection of Blood Doping
Because of the proliferation of the use of blood doping methods among certain types of athletes, advanced testing methods were developed to detect the use of the same. Here is a brief discussion on the current screening processes:
Detection of homologous blood transfusion
A test for the detection of homologous blood transfusion doping was first implemented by WADA during the 2004 Summer Olympics that was held in Athens. The screening method is called Flow Cytometry which examines and analyzes the indicators on the surface of the blood cells to ascertain whether there is blood in circulation which came from another person. Flow Cytometry works by detecting a variance in blood group antigens, which signify that there are cells in the body which are different from the athlete’s own RBCs.
Detection of autologous blood transfusion
Autologous blood transfusion can be detected by using a CO (carbon monoxide) rebreathing technique which measures potential increases in the hemoglobin mass. The method requires an athlete to inhale a mixture of oxygen and carbon monoxide for about 10 to 15 minutes. The difference in carboxyhemoglobin concentrations prior and subsequent to the rebreathing is then measured to calculate the total hemoglobin mass. This procedure, however, cannot be performed in most cases since it is not advisable for an athlete to breathe in carbon monoxide before a competition because it limits exercise performance. WADA is currently funding research initiatives to establish more advanced methods that can efficiently detect autologous blood transfusions.
Detection of erythropoietin (EPO)
Tests for EPO were first conducted at the 2000 Summer Olympic Games which was held in Sydney, Australia. The results were confirmed by the International Olympic Committee (IOC). The first test used blood screening methods while the confirmation test analyzed urine samples. In 2003, the Executive Committee of WADA accepted the recommendations of an independent report which established that urine tests alone are sufficient to detect the presence of recombinant EPO. The report further stated that urine testing is the only scientifically validated method for the direct detection of recombinant EPO although the screening procedure could be used in conjunction with blood testing.
Detection of blood hemoglogin-based oxygen carrier (HBOCs)
Hemoglobin-based oxygen carriers such as Oxyglobulin can be detected through a four-step process:
- Eliminating the abundant proteins in the blood samples using a process called immunodepletion
- Separating the capillary electrophoresis (CE) to check both the HBOC and the hemoglobin mass
- Performing UV/Vis techniques to detect the HBOC and hemoglobin mass
- Using time-of-flight (TOF) or mass spectrometer (MS) procedures to ensure the accuracy in detecting and distinguishing between hemoproteins and other proteins which determine HBOC uptake
WADA has taken various initiatives to improve the detection of abnormal blood profiles among athletes. For instance, the organization has developed a strategy called Athlete Passport which is designed to monitor an athlete’s biological variables to spot any abnormal variations that indicate the use of blood doping methods. The approach allows timely testing and intervention, as well as the imposition of sanctions. It is hoped that this policy will deter the use of doping methods in competitive sports at all levels.
Famous Blood Doping Cases
The practice of blood doping to enhance athletic performance began in the 1960s but was outlawed in 1986. Here are brief accounts of some famous athletes who used blood doping methods:
The professional racing cyclist from the Netherlands started and finished the Tour de France 16 times and won the race in 1980. He later admitted to having received blood transfusions during the 1976 competition where he had placed 2nd. At that time, blood doping was not yet considered illegal in sports and his actions went unsanctioned.
The American track cyclist represented the country in the 1984 Summer Olympics held in Los Angeles, California where he won the silver medal. He later admitted to blood doping during the event. The following year, blood doping was banned by the IOC.
Tyler Hamilton, an American cyclist, was accused of using blood transfusions, human growth hormones, testosterone, EPO, and insulin after failing his drug tests. During the 2000 Athens Olympics where he won a gold medal, his sample showed signs of blood doping. He tested positive again after a month and was subsequently banned from competition for two years.
The German speed skater won a total of nine Olympic medals – five gold, two silver, and two bronze. After the World Championships in Norway which was held in February 2009, she was accused of blood doping by the International Skating Union based on irregular levels of reticulocytes in her blood. Apparently, elevated levels had been found during a number of previous competitions. The Court of Arbitration for Sport (CAS) confirmed the imposed two-year ban, after having found no evidence of an inherited disease that could have explained the abnormal levels.
Lance Armstrong’s case is probably the most famous and controversial of all blood doping cases in cycling history. On August 23, 2012, he was stripped of his 7 Tour de France titles. He had previously denied all accusations against him but during an interview with Oprah Winfrey the following year, he admitted having using banned substances and methods including EPO and blood transfusions. Read more about Armstrong’s historical confession, here.
Athletes who misuse blood doping procedures to secure a competitive advantage that guarantees a gold medal or a streak of winnings do so at the risk of developing serious medical complications. Symptoms of these health consequences can range from a mild flu to thrombosis, organ failure, heart attack, and stroke. Fortunately, WADA, IOC, and other international sports federations are constantly updating their respective lists of Prohibited Substances and Methods, as well as developing new screening procedures with the aim of deterring blood doping and other forms of drug misuse at various competition levels. Local and international sports organizations and coaches are likewise urged to educate athletes and sports enthusiasts of the dangers of doping methods, the effects of which are not always worth the gold.