Tuesday, March 7, 2017
A study reported on February 9, 2017 in the Journal of Cardiovascular Pharmacology and Therapeutics found improvements in glucose, lipids, blood pressure and other factors, as well as a lower risk of cardiovascular events and mortality over follow-up in association with testosterone therapy.
The investigation included 656 men with low testosterone levels and symptoms of hypogonadism. Three hundred sixty men had been prescribed testosterone therapy and 296 opted not to be treated with the hormone. Total plasma testosterone, fasting glucose, hemoglobin A1c (a marker of long term glucose control), lipids, and other factors were assessed at least twice per year.
Over a median follow-up period of seven years, only two deaths (neither of which were caused by cardiovascular disease) occurred among those who received testosterone, while 21 deaths, including 19 attributable to cardiovascular disease, occurred among those who were not treated with the hormone, which was equivalent to a 12.4 times greater risk of mortality among untreated subjects. Twenty-six nonfatal heart attacks and 30 nonfatal strokes occurred among subjects who did not receive testosterone, compared to no nonfatal heart attacks and strokes in the testosterone-treated group.
In comparison with levels measured at the beginning of the study, glucose levels progressively decreased and hemoglobin A1c levels declined significantly from 6.9% to 5.6% over follow up in those treated with testosterone. In contrast, fasting glucose levels remained essentially unchanged while hemoglobin A1c increased in the untreated group. Additionally, systolic and diastolic blood pressure, heart rate, total cholesterol, low-density lipoprotein (LDL) cholesterol, non-high-density lipoprotein cholesterol, triglycerides and liver enzymes decreased in testosterone-treated men over follow-up, while increasing among untreated men.
"Testosterone therapy has been shown to reduce the risk of incidence of myocardial infarction, stroke, and mortality in men with hypogonadism," Abdulmaged M. Traish, PhD, MBA, and colleagues write. "These reports, together with the meta-analysis published by Corona et al and the FDA response to the petition to place a black box on testosterone products, suggest that no credible or substantial evidence exists for increased cardiovascular risk with testosterone therapy. Our findings which span more than 8 years with a large number of patients also confirm this premise. Thus, we point out that the earlier reports that purported increased cardiovascular risk with testosterone therapy are confounded by methodological flaws and without adequate clinical acumen that makes them inconclusive, and at best suspect, in their conclusions."