Assessing estrogen exposure from transdermal estradiol patch therapy using a dried urine collection and a GC-MS/MS...

Area of Science:

• Endocrinology
• Clinical Chemistry
• Pharmacology

Background:

• Transdermal estradiol patch therapy is commonly dosed based on patient-reported symptoms.
• Serum estradiol monitoring is invasive and impractical for routine clinical use.
• Assessing estrogen exposure is crucial for optimizing transdermal estradiol therapy.

Purpose of the Study:

• To evaluate the utility of a dried urine assay for assessing estrogen exposure.
• To determine if urinary estrogen levels correlate with transdermal estradiol patch doses.
• To establish a non-invasive method for monitoring hormone therapy.

Main Methods:

• Retrospective analysis of clinical laboratory data from postmenopausal women.
• Comparison of urinary estrogen profiles between women on varying doses of transdermal estradiol and a control group.
• Quantification of estrogen metabolites using gas chromatography-tandem mass spectrometry on dried urine samples.

Main Results:

• Significant, dose-dependent increases in urinary estradiol and other estrogen metabolites were observed with increasing transdermal estradiol patch doses (p < 0.001).
• Urinary estrogen metabolite concentrations showed significant differences before and after initiating transdermal estradiol therapy.
• The dried urine assay demonstrated sensitivity to dose variations in transdermal estradiol therapy.

Conclusions:

• A dried urine assay is a viable and non-invasive method for assessing estrogen exposure from transdermal estradiol patch therapy.
• This assay can differentiate estrogen exposure across different therapeutic doses.
• Prospective studies are warranted to correlate these findings with clinical outcomes.