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| |  NAMS: Caution Urged in Treating Andropause with Testosterone By Cameron Johnston Special to DG News NEW ORLEANS, LA -- October 5, 2001 -- Few physicians would dispute that the condition known as andropause exists in older men, but does that mean it should automatically be treated with testosterone replacements, or other forms of androgen therapy? Not according to two experts who spoke yesterday (Oct. 4) at the annual meting of the North American Menopause Society, in New Orleans, Louisiana. There are many cases of physiological/medical problems that are not solved with testosterone replacements, said Dr. Shalendar Bhasan, professor of medicine at University of California at Los Angeles medical school. For example, while it now seems to be a given that testosterone injections or scrotal patches can increase lean body mass, and help reverse the increase in body fat that older men experience, it is unclear whether this will add to a man’s muscle strength, or to his endurance when doing physical activities. Similarly, it is commonly believed that age-related impotence might be reversed, or the man might find some solace with testosterone, but this might not be the case. Testosterone has an impact on sexual activity by affecting the libido, he said. But tumescence -- the physical ability to have an erection capable of sexual activity -- appears to be independent of testosterone levels. Furthermore, studies have shown that fewer than 10 percent of men with erectile dysfunction have low testosterone, and that in older men who have normal testosterone levels, adding to their baseline levels does not appear to influence their erectile ability. "Erectile dysfunction and androgen deficiency are two distinct and independently distributed conditions," Dr. Bhasan said. Bone mineral density (BMD) is another marker of aging that is influenced by testosterone. At least three studies have shown that testosterone injections or patches can increase BMD. To date, however, this has not translated into reduced bone fracture rates for men. Perhaps the most exciting news on the androgen front, said Dr. Bhasan, is that older beliefs about testosterone and blood flow now appear to be falling by the wayside. It used to be a common belief that blood flow was slowed by testosterone, and that testosterone would increase the progression of atherosclerosis, and was a risk factor for stroke, he said. Now, based on a meta-analysis of 30 studies, it appears that testosterone does not affect high-density lipoprotein (HDL) cholesterol levels, and that testosterone supplementation, in the short-term, at least, improves arterial blood flow and improves the tone of the arterial endothelium. Nonetheless, Dr. Bhasain said: "It’s premature to suggest routine testosterone replacement therapy for all older men with low testosterone levels." This was reiterated by Dr. Glenn Cunningham, a professor of medicine and molecular cell biology at Baylor University Medical School, where he is also the vice-chair for medical research. There are a number of unknowns, when dealing with testosterone, that make the use of this hormone something of a gamble, he said. And until those questions have been answered -- and this might be a long way down the road -- a lot of caution is in order when dealing with testosterone replacement therapy. The dose of 17-methyltestosterone that would be needed to elicit the same effect in a man as it would in a women would have to be 30-40 fold greater, in the order of 50 mg per day, he said. "The interactions are too complex and there are too many of them to say with certainty that androgen replacement is protective of cardiovascular disease -- especially in older men," he said. There might also be a significant risk of androgen replacement setting off a chain of events, whereby occult prostate cancer may become clinically significant, he said. It is known, for example, that American and Japanese men both have the same incidence of prostate cancer, but for unknown reasons, the cancer progresses more rapidly, and to a greater degree, in American men than it does in the Japanese. "Do we increase the risk of this happening with the use of testosterone replacement?" he asked, and said the answer is not yet known. Testosterone could also necessitate more invasive treatments for benign prostatic hyperplasia. Part of the problem is that with respect to increasing the risk for cardiovascular disease, while the studies have shown some benefit, they were not powered to look at the long-term safety or long-term risk factors. A mammoth study to look at the long-term effects of testosterone on prostate health has been planned, but will cost more than $100 million and require 6000 men over a six-year period to carry out, he said in an interview in Doctor’s Guide. "At present time, because of the uncertainty in risk-benefit ratios, we are taking a conservative approach here. I think our position would be that our patients should present with symptoms that are consistent with androgen deficiency before we move to document and treat it. The things we are are talking about are sexual problems, weakness, frailty, lowered bone mineral density." Each of those symptoms would have to be shown clinically, and the severity would have to be sufficient to justify the use of added hormone replacements, he said. Some of the symptoms of androgen deficiency are very hard, if not impossible, to define with data. Therefore, physicians have to be careful in using subjective descriptions of a medical problem as the basis for putting their patients onto a regimen of hormone replacement therapy which could ultimately prove harmful, and for which a considerable amount of data is still lacking.
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