A man with type 2 diabetes is twice as likely to have low testosterone (low T) than someone without diabetes, according to the American Diabetes Association. Past studies have shown that each of these conditions separately may be bad for heart health.
A new study found that men with both diabetes and low T may have a higher risk for atherosclerosis (clogged arteries) than men with diabetes and normal testosterone levels.
The study was written by Javier M. Farias, MD, of the Hospital Universitario Sanatorio Guemes in Buenos Aires, Argentina, and colleagues.
The research team found that men who had low testosterone and type 2 diabetes were six times more likely to have increased thickness of carotid arteries than men with diabetes and normal testosterone levels. Carotid arteries are major blood vessels in the neck that supply blood to the brain. If the walls of these arteries become too thick, they can prevent blood flow to the brain and cause a stroke.
The same patients were also six times more likely to have endothelium dysfunction. With this condition, the inner lining (endothelium) of the blood vessels does not function normally. This can lead to plaque buildup in the arteries and create a blockage.
The researchers studied a total of 115 men with type 2 diabetes. They were 56 years old on average. They had no history of heart disease.
Just under a third of the men had low blood T levels. The rest had normal levels. Testosterone is the primary male sex hormone.
"We still need to determine whether testosterone is directly involved in the development of atherosclerosis or if it is merely an indicator of advanced disease," Dr. Farias said in a press statement. "This study is a stepping stone to better understanding the risks of cardiovascular events in men who have both low testosterone and type 2 diabetes."
Patients with type 2 diabetes produce the hormone insulin, but their bodies don’t use it well. Insulin helps cells use blood sugar.
In a press release on the study, the Endocrine Society pointed out that the number of older men getting testosterone replacement therapy jumped sharply in the past 10 years. Men often get this treatment to improve erectile dysfunction, libido, mood, muscle mass, bone density and red blood cell production.
The Endocrine Society said that some research has raised concerns about the risk of heart complications related to the therapy. The group has called for large-scale, controlled trials to assess this risk.
This study was published Oct. 16 in the Journal of Clinical Endocrinology & Metabolism.
The study authors disclosed no funding sources or conflicts of interest.