Is Free Testosterone Concentration a Prognostic Factor of Survival in Chronic Renal Failure (CRF)?

BACKGROUND Lowered testosterone level in CRF patients is associated with elevated risk of death due to cardiovascular reasons, and is influenced by many factors, including acid-base balance disorders. AIMS evaluation of testoste-rone concentration (TT) and free testosterone concentration (fT) in pre-dialysis and dialysis patients; assessment of TT and fT relationships with biochemical parameters; evaluation of prognostic importance of TT and fT in predicting patient survival. MATERIAL AND METHODS 4 groups of men: 14 - on hemodialysis (HD), 13 - on peritoneal dialysis (PD), 9 - with chronic renal failure (CRF) and 8 - healthy (CG), aged 56±17, 53±15, 68±12, 43±10 years, respectively. TT and biochemical para-meters were measured; fT was calculated. RESULTS The lowest TT and fT were observed in HD and CRF, the highest - in CG (p=0.035 for TT; p=0.007 for fT). fT in CRF and CG were different (p=0.031). TT and age was associated in HD (p=0.026). Age and fT was strongly associated in PD (p<0.001). After adjustment for age, TT was negatively associated with BMI (p=0.013) and fT was positively associated with HCO3 level (p=0.007). fT was lower in those who died during 5 years of observation than in survivors (p=0.009). We have found that, opposite to TT, fT appeared to be a better predictor of 5-year survival than age. After combining pH and HCO3 levels into a single variable - no acidosis, acidosis with HCO3 normal serum level, acidosis with low concentrations of HCO3 and adjustment for age and the study group - a trend toward the lowest values of free testosterone in decompensated acidosis was observed (ptrend=0.027). Such a trend was not seen for testosterone concentrations (ptrend=0.107). CONCLUSIONS Total and free testosterone levels were lower in HD and pre-dialysis than in healthy patients. Free testost-erone level may predict long-term survival better than age. Total and free testosterone levels are lower in metabolic acidosis and total and free testosterone levels were positively associated with HCO3 level.