(CNN) People with mental disorders have been found to be at higher risk of developing age-related diseases, but not necessarily at greater risk of aging faster — until now.
Experiencing mental disorders early in life may lead to poorer physical health and accelerated aging in adulthood, found a study published Wednesday in the journal JAMA Psychiatry.
Study participants who had a greater variety and persistence of mental disorder symptoms in adulthood — or high general psychopathology scores — were aging faster biologically by a factor of about 5.3 years between ages 26 and 45 compared to participants with the lowest scores. The disorders the higher-risk individuals experienced when they were younger included mainly anxiety, depression, substance misuse and schizophrenia.
These individuals also experienced more difficulties with hearing, vision, balance, motor functioning and cognition. Independent observers who viewed photos of this group without knowing anything about them rated them as looking older.
Since the study authors controlled for many other factors that could lead to accelerated aging, such as sex, body-mass index, smoking, childhood health and maltreatment, and socioeconomic status, the report has revealed that "there is something else there that indicates that there might be some sort of underlying biological process happening," said Elizabeth Walker, a research assistant professor at Emory University's Rollins School of Public Health in Atlanta, who wasn't involved in the study.
These findings resulted from the longitudinal Dunedin Study, which has observed and tested the biological, physical and mental health of about 1,000 New Zealanders from their birth in 1972 or 1973 until age 45.
"Normally, you have the onset of these chronic age-related diseases certainly at a later age. When we think of aging, we think of older people, people who are at the end of their 50s, mid-60s or even older," said the current study's lead author Jasmin Wertz, a postdoctoral associate with the Moffitt & Caspi team at Duke University in North Carolina. "Aging outcomes are not even measured before people reach that age. However, what we see here is that when you do measure these outcomes, you can see that people who have had that experience of mental health problems already show faster aging at what seems like a relatively young age."
The study "helps further connect the dots between what's known about the association between mental disorders and physical health problems, including early mortality," said Dr. Benjamin Druss, a professor and Rosalynn Carter chair in mental health at Emory University's Rollins School of Public Health in Atlanta, who wasn't involved in the study.
There are a few potential reasons why mental disorders could lead to faster aging, whether those reasons are due to unhealthy habits and stressors related to mental disorders, or because of the mental disorders themselves.
For example, people with mental health problems are more likely to do less exercise or have a worse diet, which are associated with faster aging, Wertz said.
People with mental health problems, and sometimes related physical conditions as well, often struggle with accessing adequate care, which is a "stressful experience," Wertz said. This group is also more likely to be exposed to violence and stigma, and just having mental disorders can take a toll on the body — often regardless of how people care for themselves.
"If you have preexisting neurological problems, or perhaps if you have a genetic disposition, that could also contribute to the risk both for mental health problems as well as faster aging," Wertz said.
Stress increases circulation of stress hormones and inflammation, which can lead to faster aging and subsequent diseases, the study said. "We think about depression as a disease that originates in the brain with chemical disturbances and things like that. But depression probably is a systemic illness that affects the entire body," said Dr. Brent Forester, a member of the American Psychiatric Association's Council on Geriatric Psychiatry and chief of the Center of Excellence in Geriatric Psychiatry at McLean Hospital in Massachusetts.
"The longer I've done this work, and the longer that I've worked with older adults in particular, the more I think of psychiatric illness as not a brain disorder, but as a whole-body disorder."
One limitation of the study is that the authors stopped observing the adults at 45, so whether their accelerated aging would continue and manifest as chronic diseases is unknown. "But I would say the longer you go and the older you go," Forester said, "the more likely you're going to see some of these medical problems cropping up earlier than later."
The findings have suggested that with better prevention, early identification and improved treatment of mental health problems, health professionals might be able to reduce and delay aging and later physical diseases, Wertz said. "There's a window of opportunity, especially because these mental health problems ... often occur relatively earlier in the life course than the physical diseases."
"People who experience these mental health problems really are a high-priority group that should be monitored as much as possible for signs of faster aging," Wertz added. "To be able to do that, you really need a great integration of the health care systems for mental health problems and those who have physical health problems, because at the moment, they're really separate."
Mental disorders can be debilitating to the point where a person can't keep up with healthy habits, and that challenge may be exacerbated by the pandemic. Seeking professional help for diagnoses, therapy and medication management is easier said than done, but if you can, it's better than "expecting yourself to manage these problems by yourself and just pushing through," Wertz said.
In the meantime, if you have the stamina, a "healthy lifestyle is key at preventing age-related disease and in preventing faster aging," Wertz added. Any amount of physical activity, safely socializing with others, reducing smoking and healthy eating can help by reducing inflammation in the body, among other benefits.