Low urinary GH levels in normal statured obese children

Area of Science:

• Pediatric Endocrinology
• Growth Hormone Physiology
• Obesity Research

Background:

• Urinary growth hormone (u-GH) is a non-invasive biomarker for assessing growth hormone secretion.
• Obesity is increasingly prevalent in children and may influence endocrine function.
• Understanding factors affecting u-GH levels is crucial for accurate growth assessment.

Purpose of the Study:

• To investigate the relationship between urinary growth hormone (u-GH) levels, body mass index (BMI), and chronological age in children.
• To compare u-GH levels between obese and non-obese children of normal height.
• To determine the influence of sex and pubertal stage on u-GH levels.

Main Methods:

• Evaluated u-GH levels in 240 children (aged 5-14 years) using a two-site enzyme immunometric assay.
• Collected samples from three consecutive first morning voidings, calculating mean concentration and excretion.
• Utilized multiple regression analysis to identify factors influencing u-GH levels.

Main Results:

• BMI and chronological age were significant predictors of u-GH levels (concentration and excretion) in all children.
• Obese children showed significantly lower mean u-GH concentration and excretion compared to non-obese children.
• Both groups exhibited a similar trend of increased u-GH levels during puberty.

Conclusions:

• Urinary GH levels are significantly associated with chronological age and BMI in children.
• Obesity is independently linked to lower u-GH levels, even in children of normal height.
• Clinicians should consider the impact of excess weight on u-GH measurements when evaluating short stature.