Age-Related Effects of Testosterone Substitution in a Very Large International Cohort of 1438 Men: The Ipass-Experience

Program: Abstracts - Orals, Poster Preview Presentations, and Posters
Session: MON 0001-0021-Effects of Regulating Sex Hormone Levels in Men
Monday, June 23, 2014: 1:00 PM-3:00 PM
Hall F (McCormick Place West Building)

Poster Board MON-0016
Michael Zitzmann, MD, PHD1 and Farid Saad, DVM, PhD2
1University Clinics Muenster, Muenster, Germany, 2Bayer Schering Pharma AG, Berlin, Germany

It is still largely unclear to what extent testosterone substitution has age-related effects. Especially outcome in regard to blood pressure or elevation of hematocrit might be different in older men compared to younger men.


The IPASS study is an international study of testosterone substitution using intramuscular injections of testosterone undecanoate 1000mg in hypogonadal men involving 1438 men (1240 men aged younger than 65 years, range 15 to 64 years, mean 46±12 years, and 198 men aged at least 65 years (range 65 to 94 years, mean 69±4 years). Substitution was monitored for 1 year.


Baseline systolic was was significantly different between groups (128±14 mmHg in younger men and 136±15 mmHg in older men, p<0.0001). Also baseline waist circumference was significantly lower in younger men (99±15 cm in younger men and 102±16 years in older men, p=0.009). Significant changes during treatment were observed in lowering body weight and waist circumference, indendent from age, but depending on pre-treatment status with other androgens. Effects of lowering systolic and diastolic blood pressure were largely seen in younger men, while a decrement in HbA1c was much more pronounced in the older group. Elevation of hematocrit was rather differential depending on pre-treatment and not on age. Changes in lipid values, PSA and psychological estimates were largely similar.


The effects of testosterone substitution using intramuscular testosterone undecanoate in hypogonadal men are partially different in younger vs older men. Older men seem to benefit more from decrement of insulin resistance while younger men have a more pronounced effect in lowering blood pressure. Other parameters seem to be independent from age.

Disclosure: FS: Employee, Bayer Schering Pharma. Nothing to Disclose: MZ

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