Androgens in Aging Men: Do Men Benefit from Testosterone Replacement?

Summary: Shit-all good comes from testosterone supplementation in old men.

Interestingness: 1

Paper by Carrie J Bagatell, MD and William J Bremner, MD, PhD in the Journal of Anti-Aging Medicine, Volume 1, Issue 4, Winter 1998.

(((This paper is the male equivalent of the previous two posts. Testosterone supplementation is much less used than estrogen and thus much less is known about it. This paper is short on numbers and graphs, so not much to report)))

Total and free testosterone levels decline during aging in men. Young men with low gonad activity (((and therefore low testosterone levels))) show lower muscle mass and higher fat content than men with normal activity. Supplementing with androgens in those men increases muscle mass, decreases fat content, increases libido and frequency of erections and ejaculation (((don't know if enough to put them back to standard levels))). This increase in sexual function does not work with older men though (((that seems to be the summary of the whole paper: it works for hypogonodal young men, it doesn't work for old men))), and most older men with erectile dysfunction do not have low levels of testosterone. Use of gonadotropin-releasing hormone analogs (GnRH) triggers a similar condition to having low gonad activity (((makes no sense to me with that name))). When this is done in older men (((prostate cancer??))), it triggers lower bone density.

In a very small study, long term use of testosterone increased libido (((partially contradicting the previous paragraph))). It did not help cognition in a different study. Improvement in hand grip strength was noted in many studies. No benefit in bone density or good bone markers were noted on older men under androgen supplementation.

Risks also don't appear to be a big deal: decreases in high-density lipoprotein (HDL) in young men and some worries about it contributing to the growth of prostate cancers exist. In older men, hematocrit and hemoglobin fraction increase a lot, with 25% of test cases developing polycythemia (((disease of the blood where too high a fraction of the volume of blood is made up of red blood cells))).

The authors think that selective androgen receptor modulators would be useful, and some are being studied in primate models (((but I fail to see the benefits))).

(((There's too few benefits shown by testosterone to pay much attention to it)))

Abstract follows:

Most cross-sectional studies and one recent longitudinal study suggest that testosterone levels in healthy men decline slowly and that this decline begins during middle age. The decline in "free" or unbound testosterone is greater than the decline in total testosterone levels. Physiologic sequellae of lower testosterone levels may include a decrease in muscle mass, increase in body fat, decreased bone density, and a variety of changes in sexual function. Long-term studies of androgen replacement are currently in progress. Short-term studies suggest that, for some men, androgen replacement may increase libido and muscle strength and decrease abdominal fat. The available data suggest that androgens do not generally worsen symptoms of prostatic hypertrophy or stimulate the development of prostate cancer. Lipid profiles may be slightly improved during androgen replacement, but the long-term effects of androgens on the cardiovascular system are unknown. Hematocrit and hemoglobin frequently rise in response to androgen administration. In most men, these increases are small, but in some men they can be significant. Liver toxicity can occur with use of alkylated androgens, but it is extremely rare with the use of testosterone esters. Men receiving androgens should have periodic monitoring of their prostate, serum prostate-specific antigen level, lipids, hematocrit, and liver functions. Future androgens, with minimal effects on the prostate, may become available for clinical use.