Neither dehydroepiandrosterone nor testosterone replacement improve body composition, physical performance, bone mineral density, insulin sensitivity, or quality of life in people over age 60 years who have low androgen levels, according to Dr. K. Sreekumarian Nair of the Mayo Clinic, Rochester, Minn., and his associates.
“The search for eternal youth will continue, but the reversal of age-related decreases in the secretion of DHEA [dehydroepiandrosterone] and testosterone through 'physiologic' replacement regimens offers no answer and should not be attempted,” Dr. Paul M. Stewart said in an editorial comment accompanying the report of Dr. Nair's findings, published in the Oct. 19 issue of the New England Journal of Medicine.
Dr. Nair and his associates conducted a 2-year study to assess the effects of full DHEA replacement in 57 women and low-dose testosterone replacement in 87 men whose low hormone levels placed them in the 15th percentile for normal younger men and women. These healthy subjects were randomly assigned to receive either active or placebo tablets and transdermal patches, and were evaluated every 3 months.
Both total and bioavailable levels of the hormones rose significantly in the subjects who received active treatment, to values that would be considered in the high-normal range for young adults. However, neither treatment “had any detectable effect on physical performance, insulin sensitivity, or the physical and mental components of the quality of life,” the investigators said (N. Engl. J. Med. 2006;355:1647–59).
Testosterone replacement caused a small but significant increase in fat-free mass, but no change in muscle area, muscle strength, or overall fitness.
Similarly, both DHEA and testosterone caused a small but significant increase in bone mineral density at the ultradistal radius in women and at the femoral neck in men. However, there were no bone mass changes at several other sites, and the magnitude of the beneficial effect was less than that reported with conventional osteoporosis therapies.
The findings confirm that neither DHEA nor testosterone is “an effective antiaging hormone supplement and argue strongly against the use of these agents for this purpose,” they noted.
In his editorial comment, Dr. Stewart observed that “another 'negative' study on the efficacy of DHEA is unlikely to have much effect on its use in Western societies.” Legally, it is classified as a dietary supplement rather than a drug, and as such it will continue to be used inappropriately, “and quackery will prevail,” he said (N. Engl. J. Med. 2006;255:1724–6).
“Companies that sell supplements may not claim that the products prevent, treat, cure, mitigate, or diagnose disease, but these guidelines are often ignored or circumvented, as appears to be the case with many current providers of DHEA,” said Dr. Stewart of the University of Birmingham (England).