Validation of salivary testosterone as a diagnostic test in the hypothalamicpituitarygonadal axis diseases
Oscar Moreno-Pérez1, Víctor Luis González-Sánchez1, Luis García de Guadiana Romualdo2, Ruth Sánchez-Ortiga1, Rocío Alfayate Guerra3, Monserrat Mauri Dot3 & Antonio Miguel Picó Alfonso1
Introduction: Salivary testosterone (Sal-T) reflects the plasma free testosterone fraction that can flow passively through the salivary glands and appears to be a strong correlation with the Calculated free testosterone (CFT) in both eugonadal and hypogonadal men. Since the collection of saliva is simple, noninvasive and inexpensive, the Sal-T is a promising tool for the screening of hypogonadism. Despite the initial interest that Sal-T has aroused, new clinical studies are needed for validation.
Objective: i) To establish the reliability of the determination of Sal-T in the diagnosis of male hypogonadism. ii) To determine the sensitivity and specificity of Sal-T for the diagnosis of hypogonadism in men using CFT as gold standard.
Methods: Cross-sectional study. Sequential sampling. Inclusion criteria: eugonadal men or with clinical suspicion of hypogonadism. Sample size: 137 individuals. Statistical analysis (SPSS 15.0.) Spearman correlation between CFT and Sal-T in the different groups evaluated. Calculating sensitivity and specificity of Sal-Tusing CFT as gold standard.
Results: We studied 137 men: 123 eugonadal (age 1844 years, BMI 24±3) 14 hypogonadal (age 1877 years, BMI 24±3). The correlation between CFT and Sal-T in eugonadal population was 0.53, while in hypogonadal population fell to 0.31. The Sal-T had a 36% of sensitivity and 98% of specificity; positive predictive value and negative predictive value were 63 and 93%, respectively.
Conclusions: i) Sal-T had a strong correlation with CFT in eugonadal population, being weak in hypogonadal population. ii) Sal-T presented a high specificity and low sensitivity in the diagnosis of hypogonadism.