From the Guidelines
Saliva testing is not a reliable method for hormone replacement therapy due to its inability to accurately reflect hormone levels in the body. The collection of saliva samples can be influenced by various factors, including the type of collection kit used, such as absorbent pad-based kits like Salivette, Pure•SAL, or RNAPro•SAL 1. These kits may introduce variables that affect the accuracy of hormone level measurements. Furthermore, saliva hormone levels do not consistently correlate with blood hormone levels, which are the standard for clinical decision-making 1.
When considering hormone replacement therapy, it is crucial to prioritize methods that provide accurate and reliable data. Blood tests measuring both free and bound hormones, such as estradiol, progesterone, and testosterone, offer more precise information for dosage adjustments. The timing of sample collection is also critical, and blood tests can be standardized more effectively than saliva collection.
Key factors to consider when evaluating the effectiveness of saliva testing for hormone replacement therapy include:
- The potential for contamination and interference from food particles, bleeding gums, and variations in saliva production
- The lack of correlation between saliva hormone levels and blood hormone levels
- The importance of standardized sample collection timing
- The preference for blood testing in clinical guidelines and treatment protocols for hormone replacement therapy, as it provides a more reliable measure of hormone levels 1.
In clinical practice, blood tests should be prioritized over saliva testing for hormone replacement therapy to ensure accurate hormone level measurements and proper dosage adjustments. This approach is supported by the most recent and highest-quality evidence, which emphasizes the importance of reliable and standardized testing methods in hormone replacement therapy 1.
From the Research
Limitations of Saliva Testing for Hormone Replacement Therapy
- Saliva testing may not be accurate for hormone replacement therapy due to various limitations, as discussed in several studies 2, 3, 4, 5, 6.
- One major problem with saliva testing is the lack of compliance sometimes seen in outpatient saliva donors, which requires strict standardization of both collection and analysis methods to achieve better comparability and assessment of published salivary hormone data 2.
- Although saliva testing has been proposed as a possible substitute for serum testing, studies have shown that there is no correlation between salivary testosterone levels and serum testosterone levels in postmenopausal women receiving transdermal testosterone supplementation 5.
- Salivary testing of testosterone concentrations is an appealing alternative because it is inexpensive and noninvasive, but the results do not support the routine use of salivary testosterone levels in postmenopausal women 5.
- Additionally, capillary blood collection tubes with gel can systematically lower estradiol and testosterone measurements, showing discrepancies with venous blood collection tubes 6.
Comparison with Serum Testing
- Serum testing is considered the gold standard for measuring biologically active testosterone, and alternative methods like salivary testing are desirable due to the cost, complexity, and limited availability of the equilibrium dialysis method 5.
- Saliva testing offers several advantages over serum testing, including simplicity, noninvasiveness, stress-free, painless, and safe collection, as well as controllable collection time and inexpensive transport of samples 3, 4.
- However, the accuracy of saliva testing in determining hormone levels is still a topic of debate, and more research is needed to establish its reliability and validity 2, 3, 4.
Clinical Use and Interpretation
- Saliva testing can be used to identify or monitor various clinical conditions, including climacteric changes, adrenal disorders, and androgen deficiency in men and women 3.
- The baseline measurement of hormone levels in saliva provides an accurate assessment, but the interpretation of results requires guidelines and standardized analytical tools 3, 4.
- The importance of timely testing and the pharmacokinetics of hormone replacement therapy should also be considered when using saliva testing for clinical purposes 4.