Stress significantly impacts both physical and emotional health. Traditionally assessed through individuals' perceptions, advancements in biomarkers now enable earlier and more effective evaluations.
Stress is a pervasive phenomenon in our lives, affecting not only emotional well-being but also physical health. Chronic stress can lead to a variety of disorders, including anxiety, depression, cardiovascular diseases, and immune system disruptions.
Despite its importance, accurately assessing stress has been a constant challenge in clinical practice and research. For decades, self-reported measures—where individuals describe their experiences—have dominated stress evaluation. Tools such as the Perceived Stress Scale (PSS), the Stress Questionnaire (SRRS), and the Job Stress Questionnaire (JSS) have been widely used in clinical psychology.
The main drawback of self-reports is their subjective nature, which can lead to discrepancies between reported experiences and physiological reality. Responses can be influenced by cognitive biases, such as the tendency to minimize or exaggerate symptoms, as well as by mood at the time of reporting.
Cultural factors and individual differences in identifying and describing stress can also affect results, limiting the accuracy of assessments. Nevertheless, self-reports remain valuable as they provide insight into the psychological dimension of stress. Ultimately, subjective experience triggers many of the emotional and behavioral responses associated with stress, making it essential to consider.
Recent technological advancements have facilitated the development of biomarkers. Unlike symptoms, which are patients' perceptions of their health, biomarkers can be measured accurately and reproducibly, independent of personal experience.
Chronic stress alters the systems that maintain our body's equilibrium (homeostasis), resulting in chemical or physiological signals that act as biomarkers. Cortisol has been the most commonly used biomarker in research and clinical practice, but its levels can vary significantly due to contextual or individual factors and can fluctuate throughout the day.
Newer, more objective biomarkers are emerging, such as heart rate variability (HRV), which measures the time variation between heartbeats and reflects the balance of the autonomic nervous system. Chronic stress alters autonomic nervous system function, resulting in typical stress symptoms and reduced HRV values. This decline serves as a potent biomarker for both stress and overall physical and mental well-being.
Quantitative electroencephalography (qEEG) can also record the electrical activity of neurons, generating detailed brain maps that identify specific activity patterns. In chronic stress situations, these maps reveal alterations.
The use of these biomarkers allows for early, objective detection independent of clinical symptoms, facilitating timely interventions and treatments before stressors have passed.
Moreover, the development of wearable devices that measure HRV (such as watches or apps) and brain activity (electroencephalographic headsets) has significantly improved stress detection. These wearable devices provide continuous monitoring without requiring individuals to visit specialized clinical laboratories.
Continuous monitoring, combined with early interventions, will enhance the quality of life for the population and reduce costs associated with stress-related illnesses. A notable example is the Finnish Institute of Occupational Health's program, which promotes HRV measurement to reduce workplace stress.
In summary, the combined use of self-reports and biomarkers overcomes the inherent limitations of each method when used in isolation. We can confidently assert that new wearable technologies for recording heart and brain activity, along with continuous monitoring capabilities, represent a revolution in stress assessment, with promising implications for public health and personal well-being.