If you are an older man and receive testosterone supplementation you will probably be no stronger, your mobility will not have improved, and neither will your cognition, according to an article published in the Journal of the American Medical Association (JAMA).
The writers explain “Male aging is associated with a gradual but progressive decline in serum levels of testosterone, occurring to a greater extent in some men than in others. Decline in testosterone is associated with many symptoms and signs of aging such as a decrease in muscle mass and muscle strength, cognitive decline, a decrease in bone mass, and an increase in (abdominal) fat mass.” Previous trials that looked at the benefits or adverse effects of testosterone supplementation have had mixed results.
Marielle H. Emmelot-Vonk, M.D., University Medical Center Utrecht, the Netherlands, and team carried out a randomized, placebo-controlled study to see what impact testosterone supplementation might have on cognition, functional mobility, bone mineral density, lipids, quality of life, body composition and safety parameters in older elderly men whose testosterone levels were less than 13.7 mnol/L over a six month period. The trial involved 207 men aged 60-80 and was carried out from January 2004 to April 2005. The men were randomly selected to receive either 80 mg of testosterone undecenoate or a placebo twice a day.
Although the men on testosterone did eventually have more lean body mass and less fat mass compared to those on the placebo, they did not have improved functional mobility, muscle strength, cognition function or bone mineral density, the researchers found. Those on testosterone did have improved insulin sensitivity, but HDL (high-density lipoprotein) cholesterol went down – HDL is the good cholesterol.
By the end of the six month period 47.8% of those on testosterone versus 35.5% of those on the placebo had metabolic syndrome – not considered a statistically significant difference.
The researchers report that quality-of-life measures were not different among the two groups, except for hormone-related quality of life. Adverse events between the two groups were not statistically different.
Testosterone supplementation was linked to an increase in blood creatinine concentrations, a measure of kidney function, and hemoglobin and hematocrit, two red blood cell measures. They also detected no negative effects on prostate safety from testosterone supplementation.
The researchers wrote “This study is, as far as we know, the largest study of testosterone supplementation with the most end points and a randomized, double-blind design. Adherence was high and the dropout rate was low. The findings in this study do not support a net benefit on several indicators of health and functional and cognitive performance with 6 months of modest testosterone supplementation in healthy men with circulating testosterone levels in the lower range.”
“Effect of Testosterone Supplementation on Functional Mobility, Cognition, and Other Parameters in Older Men – A Randomized Controlled Trial”
Marielle H. Emmelot-Vonk, MD; Harald J. J. Verhaar, MD, PhD; Hamid R. Nakhai Pour, MD, PhD; André Aleman, PhD; Tycho M. T. W. Lock, MD; J. L. H. Ruud Bosch, MD, PhD; Diederick E. Grobbee, MD, PhD; Yvonne T. van der Schouw, PhD
JAMA. 2008;299(1):39-52.
Written by – Christian Nordqvist