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PURLS: It's time to reconsider early-morning testosterone tests
Natalie Long1, Liz Nguyen2, James Stevermer1
1Department of Family and Community Medicine, University of Missouri-Columbia, MO, USA.
The Journal of Family Practice
|September 2, 2015
Summary
For men aged 45 and older, early-morning testosterone testing is unnecessary. Diurnal variation diminishes with age, making afternoon testing acceptable for this demographic.
Area of Science:
- Endocrinology
- Andrology
Background:
- Testosterone levels exhibit natural diurnal variation.
- Current guidelines recommend early-morning blood collection for testosterone level assessment.
- This recommendation aims to account for daily fluctuations in hormone concentration.
Purpose of the Study:
- To evaluate the necessity of early-morning blood collection for testosterone level testing in men aged 45 and older.
- To determine if diurnal variation in testosterone significantly impacts testing accuracy in older men.
Main Methods:
- Analysis of existing data on diurnal variation in testosterone levels.
- Comparison of testosterone level variability in different age groups.
Main Results:
- Natural diurnal variation in testosterone levels tends to diminish in men aged 45 and older.
- The age-related decrease in variation makes early-morning collection less critical for this population.
Conclusions:
- Early-morning blood collection for testosterone level testing is unnecessary for men aged 45 and older.
- Testing before 2 pm is acceptable for men in this age group due to reduced diurnal variation.
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