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Published on: October 2, 2018

Mechanisms of disease: late-onset hypogonadism

Ahmed Mahmoud1, Frank H Comhaire

  • 1Department of Medical and Urological Andrology, Ghent University Hospital, Ghent, Belgium. ahmed.mahmoud@ugent.be

Nature Clinical Practice. Urology
|August 12, 2006
PubMed

Insights

Late-onset hypogonadism, or andropause, is a condition in aging men characterized by low testosterone levels. This decline results from combined hypothalamopituitary and testicular changes.

Area of Science:

  • Endocrinology
  • Aging Male Health

Background:

  • Late-onset hypogonadism (andropause) is a syndrome linked to aging.
  • It involves typical signs, symptoms, and low serum testosterone levels.

Purpose of the Study:

  • To describe the mechanisms behind age-related hypoandrogenism in males.

Main Methods:

  • The study reviews the interaction between hypothalamopituitary and testicular factors.
  • It examines changes in gonadotropin-releasing hormone secretion and pituitary responsiveness.
  • It also assesses testicular volume and Leydig cell function.

Main Results:

  • Hypothalamic pulsatile secretion of gonadotropin-releasing hormone is reduced.
  • Pituitary gonadotroph responsiveness remains intact.
  • Testicular volume, Leydig cell mass, and function are diminished, leading to lower testosterone and loss of variability.

Conclusions:

  • Age-related hypoandrogenism stems from blunted hypothalamic GnRH secretion and reduced testicular function.
  • These factors contribute to decreased testosterone levels and loss of diurnal rhythm in aging men.

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