Reference intervals for 6-sulfatoxymelatonin in urine: A meta-analysis

Area of Science:

• Endocrinology
• Biochemistry
• Gerontology

Background:

• Melatonin's vital physiological roles are established, yet normative data for its nocturnal production are lacking.
• Urinary 6-sulfatoxymelatonin (aMT6s), corrected for creatinine, is a reliable biomarker for assessing total nightly melatonin synthesis.
• Establishing reference values for aMT6s is essential for clinical and research applications.

Purpose of the Study:

• To establish reference estimates and intervals for overnight melatonin production.
• To consolidate data from multiple studies through a comprehensive meta-analysis.
• To provide a benchmark for assessing melatonin levels in diverse populations.

Main Methods:

• A systematic meta-analysis was conducted, aggregating data from 68 distinct studies.
• The analysis included a total of 17,847 participants.
• Urinary aMT6s levels, normalized to creatinine, were analyzed to determine production norms.

Main Results:

• No significant gender-based differences in aMT6s excretion were observed.
• aMT6s levels peak in early childhood, stabilize during adolescence, and gradually decline until age 50-60.
• A slight increase in aMT6s was noted around 60 years of age, potentially linked to survival bias.

Conclusions:

• The established aMT6s reference values provide the first normative data for overnight melatonin production.
• Age-related patterns in aMT6s excretion highlight developmental and aging trends.
• Low aMT6s levels are associated with increased risk for cardiovascular, cancerous, and neurodegenerative diseases, suggesting clinical utility in identifying melatonin deficiency.