Here comes yet another reason to treat that depression pronto: A new study indicates that depression ages you.
You’ve probably heard the laundry list of ailments that depression is associated with, like cardiovascular disease, diabetes, and Alzheimer’s disease. Now there’s one more: Researchers at the University of California at San Francisco (UCSF) took blood samples from 109 people with and without major depressive disorder (all unmedicated), and found that the epigenetic clocks in depression sufferers were about two years older. This is significant, given that the participants averaged only 40 years old—meaning that over a lifespan, depression might knock off a median of four-plus years.
Cell age was calculated by tracing cells’ methylation rates, which change predictably on some genes as people age, with variation from person to person, and can be used to project remaining lifespan. The older epigenetic ages suggest that depressed people are aging faster, and face higher mortality risks. The findings held true even when researchers controlled for factors like obesity and smoking.
Earlier studies have shown similar cellular age acceleration in people with PTSD. “One of the things that’s remarkable about depression is that sufferers have unexpectedly higher rates of age-related physical illnesses and early mortality, even after accounting for things like suicide and lifestyle habits,” noted co-senior author Owen Wolkowitz, a professor of psychiatry at UCSF. “That’s always been a mystery, and that’s what led us to look for signs of aging at the cellular level.”
Note that this cellular aging may well be happening stealthily: The depressed participants did not show any outward signs of accelerated aging.
Next up, researchers hope to find out whether antidepressants shift cellular aging patterns, and to also nail down whether or not the depression itself is causing the accelerated aging, or a related mechanism.
If you are feeling depressed and need help or treatment, you can contact your primary care physician, a local urgent care, or call SAMHSA’s 24-hour National Helpline at 1-800-662-HELP (4357).