Testosterone: Terrible or Terrific?
The answer might depend on which study group you ask-and when. Facts from 3 new analyses of testosterone in action are presented in the 7 slides that follow.
The sex hormones testosterone and estrogen alter only certain cardiovascular disease risk factors to raise a man's risk of heart disease. A study of 400 healthy men, aged 20 to 50, found that higher levels of testosterone led to lower levels of high-density lipoprotein (HDL) cholesterol. Estrogen appeared to have no effect on HDL cholesterol.
In contrast, low levels of estrogen led to higher fasting blood sugar levels, worsening insulin resistance, and more fat in muscle, all markers for developing diabetes, a heart disease risk factor. The Harvard researchers found no changes in low-density lipoprotein cholesterol, blood pressure, or body weight with regulation by either testosterone or estrogen and, therefore, these common risk factors for cardiovascular disease are not regulated by sex hormones, the researchers said. The research was presented March 7, 2015, at the annual meeting of the Endocrine Society in San Diego.
Ten days after the FDA required labeling changes for all prescription testosterone products to reflect the possible increased risk of heart attacks and strokes associated with testosterone use, 2 new studies failed to find cardiovascular risk with testosterone therapy. The first study is a meta-analysis of data from 29 studies involving more than 120,000 men. “With an aging population and more and more men needing testosterone therapy, it is important to better understand its potential effect on cardiovascular health,” said lead author Pawan Patel, MD, Academic Physician at Regions Hospital in St Paul, Minnesota. “Our analysis . . . gives hope that we can do more with testosterone therapy.”
The second study
from a Wisconsin health system analyzed demographic and health data from more than 7000 men with low testosterone levels. After obtaining data from the electronic record systems of 15 hospitals and 150 clinics, the researchers looked at the combined cardiovascular event rate of heart attack, stroke, and death in men with low testosterone levels who received testosterone therapy and in those who did not. After adjusting for baseline differences including age, prior heart attack or stroke, cholesterol levels, smoking status, and length of follow-up, researchers found no difference in cardiovascular event rates between the two groups. The research underscores the need for a long-term, prospective, randomized trial to truly understand whether testosterone therapy can be used without putting men at greater risk for cardiovascular events. The researchers presented their results on March 14 and 15 at the American College of Cardiology’s 64th Annual Scientific Session in San Diego.
Decreased sexual activity and desire, not erectile dysfunction, may cause serum testosterone levels to decline in older men.Australian researchers assessed more than 1700 men, aged 70 years and older, and repeated assessments 2 years in the remaining more than 1300 men. At both visits, the men answered questions about their sexual function, and the researchers measured the men’s testosterone and related blood hormone levels.
Over the 2 years, men with declining serum concentrations of testosterone were more likely to develop a significant decrease in their sexual activity and sexual desire. The researchers conclude that in older men, decreased sexual activity and desire may be a cause-not an effect-of low circulating testosterone levels. The research was presented March 7, 2015, at the annual meeting of the Endocrine Society in San Diego.
Higher testosterone levels and lower estrogen levels in men worsen certain cardiovascular risk factors, which may help explain sex differences in heart disease. The effect of testosterone therapy on adverse cardiovascular events among men still remains controversial. Decreased sexual activity and lack of desire may lead to a decline in serum testosterone levels in older men.
Can the news about testosterone therapy get any worse-the FDA in March required class labeling to warn against possible treatment-related cardiovascular events; or, on the other hand, any better-2 large new studies find no connection between the hormone and heart attack/stroke?As that debate continues, other research findings, presented this month at the annual meeting of the Endocrine Society and at the American College of Cardiology’s 64th Annual Scientific Session, look at the role testosterone levels play in evolution of risk factors for heart disease in men and the impact of decreased libido on serum testosterone in men as they age. Get highlights in these 8 slides:   âºâº High testosterone, low estrogen linked to men’s heart disease âºâº New studies find no cardiovascular risk with testosterone therapy âºâº Low testosterone may be due to decrease in sexual activity and desire in older men
