Depression in Individuals at Clinical High-Risk for Psychosis: The Association with Life Stressors, Stress Sensitivity, and Basal Cortisol Levels Restricted; Files Only
Yuan, Emerald (Spring 2023)
Abstract
Introduction: Elevated rate of depression has climbed up to 32.8 percent. Studies suggest that the Hypothalamus-Pituitary-Adrenal Axis (HPA) axis disturbances precede depression. Previous studies have shown that CHR-P participants have higher baseline depression, Life Event Stress (LES), and Daily Stress Inventory (DSI) ratings than healthy controls. The present study investigates the associations of LES, DSI, stress sensitivity, and basal cortisol with depressive symptoms in CHR-P youth. We hypothesized that greater stress exposure, daily stress, stress sensitivity, and cortisol levels, are associated with greater depression symptoms among CHR-P youth.
Methods: The study sample included baseline data from North American Prodromal Longitudinal Study-3 (N=806, age 12 to 30). At baseline, the CHR-P group met standard criteria for CHR-P based on SIPS scores on attenuated positive symptom severity ratings. Calgary Depression Scale for Schizophrenia (CDSS) was used to measure current depressive symptom severity over the past two weeks. The modified LES and DSI were administered. Salivary cortisol, LES, DSI, and CDSS were all log-transformed in the analysis. Multiple linear regression was used to predict CDSS.
Results: CHR-P individuals have significantly higher scores in LES, stress sensitivity, DSI, and CDSS compared to controls. However, basal cortisol levels were not significantly higher in the CHR group compared to controls. Life Event Stress total score, CHR, and stress sensitivity together were positively associated with CDSS (R2=0.42, p<0.001). Stress sensitivity played a partial mediating role in the relationship between LES and CDSS, and there was no significant moderation effect of cortisol in any models.
Conclusion: Our findings suggest that stress sensitivity may be a key factor in the development of depression in CHR individuals, while cortisol levels may not play a significant role. These results underscore the importance of considering life stressors and stress sensitivity in the assessment and treatment of depression in this population and suggest the need for longitudinal follow-ups to further explore the role of cortisol as a potential biomarker.
Table of Contents
Abstract: 1
Introduction and Scientific Background: 2
Stress, the HPA Axis, and Depression 2
Cortisol and Stress 3
Cortisol and Depression 3
Clinical High-Risk for Psychosis 4
Cortisol and Psychosis 4
Depression and Schizophrenia 5
The current study 5
Methods: 7
Participants: 7
Measures: 8
Results: 10
Moderation Effect 11
Mediation Effect 12
Discussion: 13
Limitations: 14
Directions for Future Research: 15
Conclusion: 16
Tables and Figures 18
Table 1. Demographics based on Diagnostic Groups 18
Table 2. Descriptive Statistics for Predictor Variables in NAPLS 3 19
Table 3. Bivariate Correlations among Variables 20
Table 4. Final Multivariate Linear Regression for CDSS 21
Table 5. Multivariate Linear Regression by Group 22
Figure 1. Stepwise Linear Regression 23
Figure 2. LES and CDSS colored with Stress Sensitivity 24
Figure 3. Moderation Effect of CHR on LES and Stress Sensitivity respectively 25
Figure 4. Mediation Effect of Stress Sensitivity on LES to CDSS. 26
References: 27
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File download under embargo until 19 May 2025 | 2023-04-13 22:34:14 -0400 | File download under embargo until 19 May 2025 |
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