Abstract
For decades, the class of anabolic androgenic steroids has represented the most
frequently detected doping agents in athletes’ urine samples. Roughly
50% of all adverse analytical findings per year can be attributed to
anabolic androgenic steroids, of which about 2/3 are synthetic exogenous
steroids, where a qualitative analytical approach is sufficient for routine
doping controls. For the remaining 1/3 of findings, caused by endogenous
steroid-derived analytical test results, a more sophisticated quantitative
approach is required, as their sheer presence in urine cannot be directly linked
to an illicit administration. Here, the determination of urinary concentrations
and concentration ratios proved to be a suitable tool to identify abnormal
steroid profiles. Due to the large inter-individual variability of both
concentrations and ratios, population-based thresholds demonstrated to be of
limited practicability, leading to the introduction of the steroidal module of
the Athlete Biological Passport. The passport enabled the generation of
athlete-specific individual reference ranges for steroid profile parameters.
Besides an increase in sensitivity, several other aspects like sample
substitution or numerous confounding factors affecting the steroid profile are
addressed by the Athlete Biological Passport-based approach. This narrative
review provides a comprehensive overview on current prospects, supporting
professionals in sports drug testing and steroid physiology.
Key words
analytical chemistry - steroids - isotope ratio mass spectrometry - doping - anabolic steroids - nutritional supplements - isotopes