Stress-related salivary biomarkers - cortisol, dehydroepiandrosterone, alpha amylase, and suicidal ideation among young women living in Kampala's informal settlements.
TL;DR
Suicidal ideation was common, and square root-transformed morning cortisol-to-DHEA ratios were independently associated with suicidal ideation, and these findings highlight the importance of understanding suicidality through integrated biological, psychological, and social perspectives.
Abstract
Background
Young women living in informal urban settlements experience intersecting structural disadvantages that may contribute to stress-related physiological changes and suicidal ideation. Evidence on salivary stress biomarkers in this population remains limited.
Objective
To examine associations between salivary cortisol, dehydroepiandrosterone (DHEA), α-amylase, the cortisol-to-DHEA ratio, and suicidal ideation among young women in Kampala's informal settlements.
Methods
This cross-sectional analysis included 300 women aged 18-24 years recruited from three informal settlements in Kampala, Uganda. Suicidal ideation was assessed using four items from the Columbia-Suicide Severity Rating Scale. Morning and afternoon salivary biomarkers were measured using COBAS E411 and C-111 analyzers. Independent-samples t-tests compared biomarker levels by suicidal ideation status, and modified Poisson regression examined adjusted associations. The final model was used to estimate the prevalence ratio (PR) and its 95% confidence interval (CI).
Results
Overall, 46.0% reported suicidal ideation and 57.7% met the threshold for probable depression. Approximately 39% had DHEA values below published reference ranges at both collection times. Participants reporting suicidal ideation had lower square root-transformed morning DHEA levels than those without ideation (3.96 vs. 4.65; p = 0.048) and higher square root-transformed morning cortisol-to-DHEA ratios (1.19 vs. 1.00; p = 0.027). In the adjusted model, each one-unit increase in the square root-transformed morning cortisol-to-DHEA ratio was associated with a 12% higher prevalence of suicidal ideation (PR = 1.12; 95% CI: 1.04-1.21).
Conclusion
Suicidal ideation was common, and square root-transformed morning cortisol-to-DHEA ratios were independently associated with suicidal ideation. These findings highlight the importance of understanding suicidality through integrated biological, psychological, and social perspectives and reinforce the need for accessible, gender-responsive suicide prevention and mental health services in low-resource urban settings.