CHEMOMETRIC EVALUATION OF URINARY STEROID PROFILES IN DOPING CONTROL

Ten endogenous steroid hormones and metabolites were determined accord ing to the screening procedure for anabolic steroids in spot urine sam ples from 105 healthy young male athletes (control samples) and 23 mal es that tested positive for anabolic steroids in the doping control (p ositive samples). The GC-MS peak areas for each sample were normalized to total area. Multivariate data analysis by Partial Least Square Reg ression (PLSR) and using a coded Y-variable (positive samples: +1 and control samples -1) allows projection of the most systematic profile s tructures into a 2D plot revealing a clear distinction between the con trol and misuser groups. The most important determinants of the locati on in the loading plot were the ratios of testosterone to epitestoster one and androsterone to etiocholanolone. The ratio between 11-beta-hyd roxyandrosterone and 11-beta-hydroxyetiocholanolone was less important , in accordance with the fact that anabolic-androgenic steroid intake primarily affects the excretion of testosterone from the testis and to a much lesser degree adrenal steroid genesis. We present a preliminar y validation of this model (PLS1-DISCRIM) for analysing steroid profil es in doping control samples from several categories of athletes, some of which are suspected for drug misuse, and results from a one dose e xcretion study in healthy volunteers. Our findings suggest that use of multivariate PLS-regression may give valuable information about anabo lic androgenic steroid misuse in sport. When appropriately calibrated, this methodology may delineate drug misusers directly from the screen ing procedure for anabolic steroids in spot urine tests.