New research suggests that people suffering from major depressive disorder may age significantly faster, compared with people who do not suffer from depression. This is according to a study published in the journal Molecular Psychiatry.
According to the Anxiety and Depression Association of America, major depressive disorder (MDD) affects around 14.8 million adults in the US every year, and the disorder is more prevalent in women.
Previous studies have associated depression and MDD with increased risk of age-related diseases, including diabetes, cancer, obesity and heart disease, and the researchers say that "accelerated biological aging" is thought to be one of the causes of these increased risks.
Researchers say people suffering from MDD may experience accelerated aging of 4 to 6 years, compared with those without depression.
To investigate this further, researchers from the VU University Medical Center in the Netherlands analyzed 1,095 patients suffering from MDD, alongside 802 people who had recovered from MDD and 510 healthy individuals who had no history of the disorder.
The participants had a mean age of 41.6 years, and 66.8% were female.
The researchers analyzed the telomere length of each individual. A telomere is an area of repetitive DNA that sits at the end of a chromosome, protecting it from deterioration.
These telomeres shorten as a person ages, but other factors may also impact their length. Through analyzing the length of these telomeres, cellular aging can be estimated.
The findings of the analysis revealed that patients who suffer from MDD, or who have experienced the disorder at some point in their lives, have shorter telomere length, compared with individuals who do not have or have never experienced severe depression.
The investigators say their research indicates that those who currently suffer from severe depression demonstrate cellular aging acceleration by 4 to 6 years, compared with healthy individuals.
A higher severity of depression and a longer duration of depressive symptoms were both linked to shorter telomere length.
The investigators say their results were significant, even after accounting for lifestyle and health factors.
Commenting on their findings, the researchers say:
"This large-scale study provides convincing evidence that depression is associated with several years of biological aging, especially among those with the most severe and chronic symptoms."
The investigators note that although other research has suggested that lifestyle interventions may have significant benefits for the aging process, it remains to be seen as to whether the aging process could be reversed, and whether this would have an impact on depression.
"It needs to be tested whether these may be fruitful interventions in MDD patients, resulting not only in a reversal of depression symptomatology but also in restoring biological aging and consequent somatic (body) health," they conclude.
Earlier this year, Medical News Today reported on a study suggesting that exercise could reduce symptoms of depression.