Depression is a debilitating disease, with both psychological and physiological impacts. Researchers previously knew that people who suffer from depression also have an increased risk of succumbing to some age-related conditions, such as dementia, cancer, heart disease and type 2 diabetes, but why depression was linked with that particular class of disease remained a mystery, LiveScience reports. Now, new research points to a possible culprit mechanism: depression may be prematurely aging people’s cells.
Researchers in the Netherlands came to this conclusion by examining telomeres—structures that occur at the end of chromosomes to protect DNA during division, and that tend to naturally get shorter as a person ages. They looked at the telomeres of 1,900 people who had suffered or were suffering severe depression and of 500 other people, who had never gone through a significant bout of depression, LiveScience reports. The participants ranged in age from 18 to 65.
Telomeres in the depressed group turned out to be shorter than those of the control group, with a difference equivalent to several years of accelerated aging. Premature aging is likely exasperated by other depression-related conditions, such as alcoholism, the BBC adds.
For now, the research falls in the realm of correlation rather than causation. But the team suspects that depression does indeed cause some of the cellular aging, independently of unhealthy lifestyle choices. “The severity of a person’s depression, as well as a longer duration of symptoms were linked with shorter telomere length, and the results held after controlling for weight, smoking, drinking and several other factors that may contribute to aging,” LiveScience explains.
The research does not address whether the shorter telomeres directly translate into health problems, the BBC points out, and researchers do not know if the process is reversible.
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