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Your passport, please

What biological values and ratios does the UCI's "Biological Passport" track?

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Dear Explainer,
I know the basic, broad principles of the biological passport, and what it is trying to accomplish. However, I don’t know any of the specifics.

Exactly what biological values and ratios does the biological passport track, and what types of changes in those values and ratios would be considered abnormal?
Steve Wells
Seattle, Washington

Dear Steve,
The UCI’s Biological Passport dates back to 2007, but the idea has been around for a while. The UCI began assembling longitudinal medical profiles on all Division I (later ProTour and Pro Continental) riders more than 10 years ago. That effort was formalized with the Biological Passport program and it now – as the Pellizotti case reminds us – has the added teeth of an enforcement mechanism.

In 2008, the UCI required that all ProTour and Continental Pro riders, as well as a select group of other riders, participate in the program which maintains an individual medical record on about 800 riders. That record is used to establish a profile based on medical samples taken over time. Over the course of a year, that includes both in-competition and out-of-competition blood and urine tests, as well as the results of general medical check-ups. According to the UCI, the data represents an average of about 10 tests per rider, per year.

With a baseline established, results from subsequent tests are compared to the general parameters of that original profile. The UCI has appointed a nine-member panel to review the data, but has not spelled out specific guidelines on how a specific sample might be considered to be statistically aberrant. Instead, each member of that panel is given relative freedom to examine the data and to flag what he deems to be suspicious.

Once flagged, the panel member can raise his concerns with other panelists, who review the data. If the group reaches a consensus that there is “sufficient evidence which determines guilt at agreed level of certainty,” the panel can recommend to the UCI that it pursue a doping case.

In essence, the approach is a condensed and accelerated “peer-review process” with one or more member making a case for further investigation, which is then subject to review by the rest of the panel. They’re not slouches, either. Former UCI Anti-Doping coordinator Anne Griper put together a solid group of specialists in their respective fields. The group includes Michael Ashenden, the head of Science and Industry Against Blood Doping Consortium; Michael Audran, a pharmacy professor at the University of Montpellier; Bo Bergland, a professor of chemistry and medicine at Stockholm’s Karolinska University; Giuseppe d’Onofrio, a professor of hematology at the Policlinic A. Gemelli in Rome; Pierluigi Fiorella, the director of the Olympus Medical Center in Ravenna, Italy; Giuseppe Fischetto, head of the medical department at the Italian Athletic Federation; Oliver Hermine, a professor of hematology at Necker Hospital in Paris; Robin Parisotto, an independent researcher, who has worked with the Australian Institute for Sport and Olaf Schumacher, a member of the sports medicine faculty at the University of Freiburg in Germany.

With records of blood and hormone profiles available, panelists look for statistical variations that wouldn’t occur due to natural causes. For example, an unexpected spike in hematocrit levels (the percentage of red cells in a blood sample) might be attributed to natural cause, such as dehydration. Ashenden, however, focuses on more subtle factors, like changes in the production of reticulocytes (new red blood cells). Changes in those levels – a statistically significant increase or decrease – might point to EPO use or blood doping.

Others might look for unexpected variations in hormone levels. In both cases, the Passport provides a much more precise tool than do the simple, one-time blood or urine tests.

The Passport program may, or may not, be the be-all-and-end-all means by which the sport can monitor and control doping in the peloton, but it’s surely one of the most effective tools available.

Essentially the Passport narrows the window of opportunity to manipulate natural blood and hormone levels. Think about the old “50 percent rule,” that the UCI imposed in 1997. Based on data that showed that the average adult male endurance athlete showed a hematocrit level of 45, the UCI took that number and applied a limit that represented the mean, plus two times the standard deviation, meaning that it covered about 95 percent of the sample group. Then those riders whose normal hematocrit levels fell above that upper limit had to provide extensive medical records to show that their results were natural in origin. Otherwise, the UCI required riders to “rest” for two weeks until their levels returned to normal. It was that ─ and not a positive doping test ─ which resulted in Marco Pantani’s ejection from the 1999 Giro d’Italia.

The problem with that broad standard was that it essentially established an upper limit for doping. If a rider’s natural hematocrit level was, say, 41 or 42 percent, he could then use EPO to dope himself up to 49.8. The introduction of the urine test for EPO in 2001 added another layer of control, but you might recall that the test could only detect the isoforms of recombinant erythropoietin for three or four days after injection, while the benefits could last for weeks.

The Passport cuts that down. Now, if our hypothetical rider wants to manipulate his blood values, there is a baseline of comparison and, even if he does dope, the benefits would have to be much smaller as he tries to keep the resulting blood profile changes within a narrow window that won’t trigger suspicion when a sample is examined.

Will the Passport stop doping? No, but it sure makes it harder and it and it reduces the performance enhancements a doping cheat might expect to enjoy.


Email Charles Pelkey

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