A recent scientific review, published in Frontiers in Psychiatry, explored the latest research on how stress throughout life influences aging and contributes to the development of psychiatric disorders. The study was led by researchers from the D’Or Institute for Research and Education (IDOR), the Federal University of Rio de Janeiro (UFRJ), the Federal University of Maranhão (UFMA), and collaborating institutions in Germany and Canada. 

Key factors play a crucial role in how aging and psychiatric disorders intersect. These factors can shape susceptibility to certain conditions, creating specific endophenotypes—underlying traits that predispose individuals to mental health challenges over time. 

At the heart of this research is the concept of allostatic load (AL), which refers to the cumulative wear and tear on the body caused by chronic exposure to stress. Prolonged stress responses can lead to dysfunction in various bodily systems. Elevated AL levels have been linked to metabolic disorders, neurodegenerative diseases, mood disorders, and increased mortality rates. Given these implications, the researchers aimed to understand how chronic stress influences aging and heightens the risk of psychiatric conditions. 

New Insights on Aging, Stress, and Mental Health 

The authors analyzed recent studies to provide a comprehensive picture of how chronic stress interacts with aging and its role in mental health challenges, particularly in older populations. 

One Brazilian study included in the review examined how aging affects the body’s response to sudden stress, focusing on the startle reflex. This automatic reaction to unexpected stimuli, such as loud noises, is modulated by a phenomenon called prepulse inhibition (PPI). PPI occurs when a weaker stimulus precedes the startling one, reducing the startle response. Disorders like schizophrenia disrupt this sensory-motor gating mechanism, leading to impaired PPI. 

The findings revealed that aging reduces the intensity and speed of the startle reflex and significantly diminishes PPI in older individuals compared to younger ones. While these changes were not directly linked to cognitive performance, they shed light on how aging impacts sensory-motor integration. 

Another study from China examined the relationship between mood disorders, executive functions (such as planning and organization), and markers of brain dysfunction. Researchers compared 50 individuals with late-life depression to 50 with Alzheimer’s disease. They found that Alzheimer’s patients experienced greater impairments in executive functions. These impairments were assessed using the Trail Making Test (TMT) A and B, which measure skills like task-switching and problem-solving. “Late-life depression is often mistaken for early dementia. Properly distinguishing between these conditions is critical for effective treatment,” explains Dr. Felipe Sudo, a researcher at IDOR and one of the study’s authors. 

The research emphasized the value of accessible tools like the TMT in low-resource settings where advanced diagnostics, such as cerebrospinal fluid analysis, may not be available. 

A pilot study from the University of Hong Kong explored the effects of computerized cognitive training on executive dysfunction in 28 individuals with late-life depression. Participants attended two sessions per week over six weeks. The results showed significant improvements in global cognitive function and revealed correlations between reduced depression severity and increased levels of BDNF, a protein essential for neuronal repair and brain plasticity. Although the sample size was small, the findings suggest that cognitive training interventions could help address cognitive deficits associated with late-life depression. 

Lastly, another study from China investigated how stress related to medical conditions can influence mood disorders. Adults undergoing surgery for tear duct obstructions—a condition causing watery eyes, blurred vision, and dry eye syndrome—reported heightened symptoms of anxiety and depression. These findings underscore the psychological toll of sensory and physical discomfort. 

Toward a Multidisciplinary Approach 

This review provides a deeper understanding of how chronic stress influences aging and mental health. The findings emphasize the importance of a multidisciplinary approach, integrating neuroscience, genetics, and psychology, to develop effective interventions that mitigate the harmful effects of lifelong stress.