Friends and family members have a harder time detecting depression symptoms in happy, extroverted people than in introverted people, especially in older people, according to a new study.
That's because close friends and relatives may have trouble seeing happy and agreeable people as being sad or depressed, said study researcher Paul D. Duberstein, a psychiatry professor at University of Rochester Medical Center in New York.
"If I know someone is extroverted, I know they'll be warm, social, agreeable," Duberstein told MyHealthNewsDaily. "It's extraordinarily difficult for people to see that person as anything other than that."
Researchers asked nearly 200 people ages 60 and older to reveal whether they were depressed or had a history of depression. They also gave the participants a personality test that rated their levels of extroversion, and interviewed their friends and family members about whether their loved ones had ever been depressed.
Even after accounting for factors such as closeness and the length of the relationship, the findings revealed the more extroverted the person was, the less likely friends and family members were to notice symptoms of depression .
Duberstein didn't expect this, he said, as he expected introverts would have a harder time expressing signs of depression.
"We ran these analyses so many different ways to make sure the findings were robust, and I couldn't make the finding go away," he said.
Even though the study was conducted in older people, the findings could apply to younger people , too, he said.
"The bigger picture idea is that when depression is missed, it's not missed randomly," Dubenstein said. "People with certain personality styles are more likely to experience depression that is missed by friends and family members, that's the bottom line."
If family and friends tell doctors that their extroverted loved one isn't suffering from depression, doctors should take that information with a grain of salt, he said, and family and friends shouldn't assume anything, either.
"Simply because someone is happy, outgoing, sociable, warm and gregarious, does not mean they are immune from depression," Dubenstein said.
The study was part of broader research examining why older people have higher rates of suicide than younger people. In those findings, older people who were imaginative and open to new experiences were less likely to commit suicide than people who are narrow-minded and inflexible, he said.
Next, researchers hope to find more factors that account for missed depression in older adults, and to see if people have expectations of older adults that lead them to miss or minimize mood disorders.
The study was published online Oct. 7 in the journal International Psychogeriatrics.
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