Recent research conducted at McMaster University indicates that inhabiting socially and economically underprivileged urban areas, coupled with experiencing depressive feelings, may be factors that accelerate biological aging.
The study, made public on June 5 in The Journals of Gerontology, Series A: Biological Sciences and Medical Sciences, found an independent association between residing in urban settings marked by pronounced resource and social opportunity disparities, and manifestations of depression, with premature biological aging. These relationships held true even after accounting for personal health and behaviour-linked risk factors such as chronic diseases and harmful health practices.
Parminder Raina, a professor from the Department of Health Research Methods, Evidence, and Impact at McMaster University, directed the study with a team that included researchers from the Netherlands, Norway, and Switzerland.
In this study, two epigenetic clocks, or DNA methylation-based estimators, were used to examine cellular aging and estimate the gap between chronological and biological age, explains Divya Joshi, the study’s lead author and a research associate in the same department at McMaster.
The study found a positive association between neighbourhood deprivation and depressive symptoms with an accelerated epigenetic age as gauged by the DNAm GrimAge clock. This reinforces the expanding evidence that living in urban areas with higher deprivation levels and experiencing depression symptoms both contribute to premature biological aging.
The study quantified depressive symptoms using a standardized depression scale with 10 items. It concluded that an increase in the depression symptom score by one point equated to a one-month escalation in the risk of death. The research team speculated that the emotional strain from depression could cause increased biological wear and tear, and destabilization of physiological systems, ultimately leading to premature aging.
The researchers assessed material and social deprivation in neighbourhoods using two indices developed by the Canadian Urban Environmental Health Research Consortium (CANUE) based on the 2011 census.
Social deprivation refers to a deficiency in family and community social resources, while material deprivation signifies an inability to access modern life necessities such as decent housing, healthy food, a car, high-speed internet, or a neighbourhood with recreational facilities. The researchers found a nearly one-year increase in the risk of death for those subjected to greater neighbourhood deprivation as compared to lower deprivation.
However, the study did not establish a magnified effect of depressive symptoms on epigenetic age acceleration due to neighbourhood deprivation.
Joshi states that irrespective of depression symptoms, the effect of neighbourhood deprivation on epigenetic age acceleration remained consistent, suggesting that the influence of depression on epigenetic age acceleration is not related to neighbourhood deprivation.
The research incorporated epigenetic data from 1,445 participants registered in the Canadian Longitudinal Study on Aging (CLSA), a study tracking over 50,000 participants aged between 45 and 85 at the time of recruitment.
Raina, the lead investigator of the CLSA and the study’s senior author, underscored the importance of longitudinal studies like the CLSA for confirming associations like those found in this research. Over a 20-year period, the CLSA will provide insights into the stability or reversibility of epigenetic changes and the mechanisms causing accelerated epigenetic aging.
The CLSA receives funding from the Government of Canada via the Canadian Institutes of Health Research and the Canada Foundation for Innovation. The European Union Horizon 2020 Programme also provided additional support for this study.
Frequently Asked Questions (FAQs) about Accelerated Biological Aging
What was the main finding of the study conducted at McMaster University?
The research found that living in economically and socially disadvantaged urban areas and experiencing symptoms of depression independently accelerate biological aging.
How was biological aging measured in the study?
The study used two DNA methylation-based estimators, also known as epigenetic clocks, to measure aging at the cellular level and estimate the difference between chronological and biological age.
How were depressive symptoms quantified in the study?
Depressive symptoms were quantified using a standardized depression scale with 10 items. An increase in the depression symptom score by one point was associated with a one-month increase in the risk of death.
What were the indices used to assess neighborhood deprivation?
The study used two indices developed by the Canadian Urban Environmental Health Research Consortium (CANUE) based on the 2011 census to assess material and social deprivation in neighborhoods.
Did neighborhood deprivation amplify the effect of depressive symptoms on biological aging?
No, the study did not find that neighborhood deprivation amplified the effect of depressive symptoms on biological aging. These factors seemed to contribute to accelerated aging through separate mechanisms.
More about Accelerated Biological Aging
- McMaster University
- The Journals of Gerontology, Series A: Biological Sciences and Medical Sciences
- Canadian Longitudinal Study on Aging (CLSA)
- Canadian Urban Environmental Health Research Consortium (CANUE)
- Canadian Institutes of Health Research
- Canada Foundation for Innovation
- European Union Horizon 2020 Programme