The proportion of men who experience symptoms of depression may be similar to the proportion of women with depression when doctors look for non-traditional symptoms, according to a new study.
Researchers found that one third of both men and women met the criteria for a depression diagnosis when traditional and alternative symptoms - such as aggression and sleep problems - were taken into account.
"You end up getting very similar rates of depression," Lisa Martin, the study's lead author from the University of Michigan in Dearborn, told Reuters Health.
About 16 percent of Americans currently meet the criteria for depression, Martin and her colleagues write in JAMA Psychiatry. Previous research has found women are about twice as likely as men to be diagnosed with the condition.
Other studies, however, have suggested that men don't exhibit the same symptoms of depression as women. Or, they may not be as willing to divulge their symptoms to a doctor.
For example, previous studies found that depressed men are more likely to show signs of anger, self-destruction, self-distractions and irritability rather than outward sadness.
For the new study, Martin and her colleagues used data from a nationally-representative survey of 3,310 women and 2,382 men that is used to measure the prevalence of mental illness.
When the researchers used a scale that was designed to assess depression symptoms common among men, they found about 26 percent of men and about 22 percent of women met the criteria for depression.
When they used a scale that included both traditional and alternative symptoms, there was little difference between the two groups: about 33 percent of women met the criteria for depression, compared to about 31 percent of men.
"Paying attention to a couple of these other symptoms allowed men who didn't really meet the threshold of symptoms to be considered," Martin said.
"Right now we're in an interesting place where clinicians and some research say we really need to pay attention to (alternative depression symptoms)," she added.
In addition to decreasing quality of life, previous research has suggested depression is linked to smoking, alcohol use, inactivity and trouble sleeping, according to the U.S. Centers for Disease and Control and Prevention.
Martin said her research and past findings suggest doctors should change how they assess their patients to help identify those experiencing or at risk for depression.
"It doesn't do us a lot of good to know more men get depression more than we thought if we can't get them through the door to get help," Martin said.
"How we advertise for support groups and how we do outreach to people needs to change," she said, adding that people need to know that depression is not just a female disease.
She cautioned, however, that her study did have limitations, including that the surveys did not include questions about overworking, over exercising, changes in sexual behavior and other markers for depression among men.