- Researchers are reporting that low baseline testosterone levels are associated with increased risk of all-cause mortality.
- They add that very low levels of testosterone are linked to an increased risk of cardiovascular death.
- Their research looked at 11 studies involving 24,000 subjects.
A study published today in the journal Annals of Internal Medicine is reporting that low testosterone in men can mean a shorter life span.
Researchers from the University of Western Australia collaborated with researchers from Australia, North America, and Europe in a systematic review and meta-analysis of 11 studies involving more than 24,000 subjects.
The researchers wanted to examine associations of sex hormones with mortality and cardiovascular disease risk in aging men.
They concluded that low baseline (endogenous) levels of testosterone in men are associated with increased risk of all-cause mortality and very low levels are associated with increased risk of cardiovascular death.
The researchers said in a statement that their study clarifies what they said are previous inconsistent findings concerning the connection between sex hormones and key health outcomes in aging men.
They examined prospective cohort studies, previously identified in a published systematic review, of “community-dwelling men with total testosterone concentrations measured using mass spectrometry and at least five years of follow-up.”
The team looked at individual patient data to understand relationships between baseline hormone concentrations (total testosterone; sex hormone-binding globulin, luteinizing hormone, dihydrotestosterone, and estradiol) and relative risk for cardiovascular events, cardiovascular disease deaths, and deaths from all causes.
According to the data, the researchers said only men with low total testosterone concentrations had higher risks for all-cause mortality.
They said a key finding was that men with a testosterone concentration below 7.4 nmol/L (<213 ng/dL) had higher risk for all-cause mortality, regardless of LH (luteinizing hormone) concentration.
LH is a chemical messenger in a person’s bloodstream that controls the actions of certain cells or organs and plays an important role in sexual development in children and fertility in adults.
The data showed men with a testosterone concentration below 5.3 nmol/L (<153 mg/dL) had an increased risk of cardiovascular death.
The author of an editorial accompanying the study suggested the meta-analysis is particularly valuable because of its rigorous methodology.
The researchers said their study is the first of its kind to perform IPD meta-analysis of major prospective cohort studies that used
To perform the IPD meta-analysis, the researchers obtained raw data from nine of the included studies and reanalyzed the combined data. They said that allowed for “more sophisticated analysis of combined data from multiple studies and provided more robust testing for associations.”
Dr. Yu-Ming Ni, a cardiologist and lipidologist at MemorialCare Heart and Vascular Institute at Orange Coast Medical Center in California, told Medical News Today the study wasn’t clear about why the subjects had low testosterone.
“There may be many reasons, including obesity, liver issues, drug interactions, and other hormonal reasons for low testosterone,” said Ni, who wasn’t involved in the research. “Unless this is clarified in future research, it is uncertain whether low testosterone causes cardiovascular disease and it would be unwise and potentially dangerous to assume that treatment of low testosterone with hormone replacement will reduce heart disease.”
Ni cited one study published in the New England Journal of Medicine as saying treatment of hypogonadism with testosterone replacement was not associated with higher rates of heart disease “and certainly not lower rates of heart disease.”
“Therefore, this study provides interesting information about the relationship between testosterone levels and heart disease, and further research is needed,” Ni said.
Dr. S. Adam Ramin, a urologist, urologic oncologist, and medical director of Urology Cancer Specialists in Los Angeles addressed whether men should take testosterone supplements.
“This study confirms what I also discuss with my patients regarding risks of low testosterone,” Ramin, who was not involved in the research, told Medical News Today. “Although most people think of testosterone in terms of sexual function, this male hormone has many functions. It is true that low testosterone will lead to lower sexual desire and possibly difficulty with erections.”
Ramin said low testosterone is also associated with loss of bone density, loss of muscle mass, weight gain, moodiness, fatigue, and depression. He said low testosterone may also lead to heart attacks, strokes and death.
“In my practice, most of my older male patients in their 80s and 90s who are spry, cognitively sharp, energetic, independent, muscular with strong stature and posture, have natural testosterone levels greater than 500, some in 600 to 700 levels,” Ramin said.
He added that men can naturally boost testosterone by losing belly fat, sleeping at least 6 hours each night, and avoiding processed foods.
Ramin noted that men should do at least 30 to 45 minutes of cardiovascular exercise at least three times a week, avoid alcohol as much as possible, drink more than 3 liters of water per day, and consume two to four eggs with the yolk per week.
He also said men with low testosterone “taking DHEA 25-75 mg per day may help. However, it must be done under supervision of a doctor to make sure there is no prostate cancer.”
Ramin said men can also take 2,000 to 4,000 IU of vitamin D3. He said men with low testosterone should avoid supplements with estrogenic compounds and bioflavonoids.