Gynecomastia — enlarged breast tissue in men that’s not caused by excess weight — was associated with a 37 percent higher risk of death before the age of 75, according to a first-of-its-kind study, published on January 16 in BMJ Open. Having a preexisting risk factor, such as cancer or circulatory, lung, and gut diseases before diagnosis were associated with the highest risk.
The markedly increased risk of premature death found here should warrant medical attention, says study coauthor Anders Juul, MD, PhD, a professor of growth and reproduction and an endocrinologist at Rigshospitalet in Denmark.
“Clearly, newly developed gynecomastia should be considered by the evaluating doctor as the ‘canary in the coal mine,’” says Dr. Juul. Physicians should look for the underlying cause, follow these patients more closely, or both, he adds.
Because gynecomastia is so common in older men, doctors often assume it’s obesity driven and may not always investigate the cause, says Joseph Aloi, MD, a professor of endocrinology and metabolism at Wake Forest University School of Medicine and an endocrinologist at Atrium Health–Wake Forest Baptist in Winston Salem, North Carolina.
“These findings suggest that when men present with gynecomastia, that their doctor should take a deeper look at potential underlying conditions that could be causing it,” says Dr. Aloi, who was not involved in the study.
More Than 3 in 10 Men Will Have Gynecomastia at Some Point in Their Lifetime
Gynecomastia is the benign — meaning harmless and not cancerous — enlargement of male breast tissue that’s usually caused by a hormone imbalance. Research estimates that at least 3 in 10 males will have gynecomastia in their lifetime, making it the most common breast condition in men.
The condition is distinct from what is often dubbed “man boobs,” or pseudogynecomastia, which is usually associated with being overweight or obese.
What Causes Gynecomastia?
The development of gynecomastia can occur at any age, but it’s typically prompted by changes in sex hormone levels that occur in newborn babies, puberty, and older age, says Detlev Erdmann, MD, PhD, a plastic surgeon at Duke Health in Durham, North Carolina, who performs surgery for gynecomastia. Dr. Erdmann was not involved in the study.
The condition is most common in older men because of the decline of testosterone levels, and is often accompanied by weight gain, which in turn can make it worse, says Aloi.
Although hormonal imbalances are the most common cause, gynecomastia can also be caused by medications and conditions such as adrenal tumors, alcoholism, kidney disease or kidney failure, liver disease, and thyroid disease.
Participants Were Followed for Up to 25 Years
Gynecomastia has previously been considered a cosmetic issue that mostly occurs in elderly obese men, and so it doesn’t get much medical attention, says Juul.
According to the authors, although earlier studies have found a link between gynecomastia and an increased risk of poor health, it isn’t known if the condition is linked with a higher risk of dying early.
To investigate, researchers used Danish national health registries to identify more than 23,000 men diagnosed with gynecomastia between January 1995 and June 2021. About 40 percent of the men were aged between 19 and 40 years old at diagnosis.
They were each matched by age and date of diagnosis with five randomly selected men without the condition for a total of about 140,000 people.
The men with gynecomastia were divided into two groups:
- Those with idiopathic gynecomastia, meaning the cause of the condition is unknown, and it isn’t caused by a known underlying health issue)
- Those with a known preexisting condition or taking medication associated with gynecomastia
Higher Risk of Death Was Mainly in Men With a Known Preexisting Condition That Caused the Gynecomastia
All participants were monitored from the date of study entry to death or the end of June 2021, whichever came first. Researchers found that there was a 37 percent higher risk of early death from any cause in the men with gynecomastia than among those without the condition.
However, when they looked at each group, the risk for increased death was mainly in the men with a known preexisting condition or taking a medication associated with gynecomastia — not the men with idiopathic gynecomastia.
“So what this study shows is that gynecomastia itself doesn’t cause an increased risk of death, but gynecomastia can be caused by an underlying medical problem that does increase the risk of death,” says Erdmann.
The conditions associated with the greatest risks were:
- preexisting cancers, with a 74 percent heightened risk
- circulatory diseases, which include things like stroke and heart disease, with a 61 percent heightened risk
- lung diseases, with double the risk
- gut diseases, with a fivefold heightened risk
Interestingly, neurological disease was associated with a 29 percent lower risk of early death.
Among individual cancers, those of the digestive tract (39 percent heightened risk), genitalia (3-fold greater risk), and lymph system (double the risk) were associated with the greatest risks.
Looking at specific gut diseases, those of the liver (12-fold heightened risk) and disorders of the gallbladder, biliary tract, and pancreas (14-fold heightened risk) were associated with the greatest risks.
The men with idiopathic gynecomastia weren’t generally at greater risk of an early death than men in the control group, except for a twofold increased risk of death from liver disease.
Because the study was observational, it can’t establish what caused the risk of earlier death or explain the increased mortality risk for specific diseases. “For example, why do men diagnosed with gynecomastia have a fivefold increased risk of dying from liver disease? I do not know. More research is needed to unravel these associations,” says Juul.
Researchers also acknowledged that they weren’t about to account for potentially influential factors, such as obesity, exposure to endocrine-disrupting chemicals, and steroid use.
Because of Increased Early Death Risk, the Underlying Causes of Gynecomastia Should Be Investigated
“The increased risk of death found here suggests that if a patient comes in with gynecomastia, it could be a sign of an underlying medical problem that we should look into,” says Erdmann. This should be done before the condition is treated or surgically addressed, he adds.
The authors agree, concluding, “These results should therefore prompt thorough clinical examination to identify the underlying risk factors.”
But there is no one-size-fits-all solution, says Juul. “There are many reasons behind the adult development of breast tissue in men, and each case should be carefully evaluated, and options individualized,” he says.