High testosterone ups heart disease risk in men

High testosterone levels may put men at a higher risk of heart disease, a new Harvard study claims.

Why men have more heart disease than premenopausal women has been unclear, but the study shows sex hormones testosterone and estrogen alter cardiovascular risk factors in a way that raises a man's risk of heart disease.

Men have higher testosterone and lower estrogen levels than premenopausal women.

Doctors have suspected that testosterone may promote cardiovascular disease or that estrogen may protect against it, or both, said Elaine Yu, the study's lead investigator and an assistant professor at Harvard Medical School, Boston.

Their study, conducted in 400 healthy men ages 20 to 50, found that higher levels of testosterone led to lower levels of HDL cholesterol, or "good" cholesterol, but estrogen appeared to have no effect on HDL cholesterol.

In contrast, the investigators reported that low levels of estrogen led to higher fasting blood glucose (sugar) levels, worsening insulin resistance and more fat in muscle, markers for developing diabetes, which is itself a risk factor for heart disease.

"These observations may help explain why men have a higher risk of cardiovascular disease," Yu said.

Yu and her research team were able to determine whether estrogen or testosterone regulated various cardiovascular risk factors by comparing two groups of men whose hormone levels were temporarily changed with combinations of medications.

At the start of the study, all men received the drug goserelin (Zoladex, AstraZeneca) to suppress their own production of testosterone and estrogen.

Then the 198 men in the first group received daily treatment for four months with either a placebo (dummy) gel or one of four doses of testosterone gel (AndroGel, AbbVie), ranging from low to high (1.25 to 10 grams).

View original post here:

High testosterone ups heart disease risk in men

Word Count: 293