Salivary Biomarkers of Psychological Stress in Women: A Systematic Review with Focus on Indian and South Asian Populations

Abstract

Background: Psychological stress represents a significant health burden among women globally, yet objective assessment tools remain limited, particularly in low- and middle-income countries. Salivary biomarkers offer non-invasive alternatives to traditional stress measurement methods, but evidence from Indian and South Asian populations remains sparse despite representing a substantial portion of global women.

Methods: We conducted a systematic review following PRISMA 2020 guidelines, analyzing studies published between 2015-2025. Original research investigating salivary biomarkers of psychological stress in women was included. Multiple databases including PubMed, Semantic Scholar, and Consensus platforms were searched. Data extraction captured study characteristics, biomarker types, analytical methods, and methodological quality, with emphasis on geographic distribution and population representation.

Results: Analysis of 130 studies revealed that 46 studies (35%) originated from Indian and South Asian populations, demonstrating significant regional research activity. Cortisol was the predominant biomarker across all populations, measured in 85% of studies, while other biomarkers including alpha-amylase (15%), immunoglobulin A (8%), and cytokines (12%) received substantially less attention. Significant methodological disparities emerged between high-income and low- and middle-income countries, with the former demonstrating greater biomarker diversity, larger sample sizes, and more sophisticated analytical approaches. Most studies (78%) were cross-sectional in design, with limited longitudinal follow-up and few direct comparisons with blood biomarkers.

Conclusions: While salivary cortisol demonstrates consistent associations with psychological stress in women across diverse populations, significant research gaps persist. The predominance of cross-sectional studies, limited biomarker diversity in low- and middle-income countries, and insufficient validation against blood-based markers constrain clinical translation. Standardized protocols, larger longitudinal studies, and validation of population-specific reference ranges are urgently needed to translate salivary biomarkers into routine clinical practice for underserved populations.