Religious Involvement, Inflammatory Markers and Stress Hormones in Major Depression and Chronic Medical Illness

Clive J Robins,Harold G Koenig,Harvey Jay Cohen,Michael B King,Sally F Shaw,Noha Daher,Denise L Bellinger,Bruce Nelson,Michelle J Pearce,Lee S Berk

doi:10.4236/ojpsych.2014.44040

Abstract

Background: Religious practices/experiences (RPE) may produce positive physiological changes in patients with major depressive disorder (MDD) and chronic medical illness. Here, we report cross-sectional relationships between depressive symptoms, RPE and stress biomarkers (pro-/anti-inflammatory measures and stress hormones), hypothesizing positive associations between depressive symptoms and stress biomarkers and inverse associations between RPE and stress biomarkers. Methods: We recruited 132 individuals with both MDD and chronic illness into a randomized clinical trial. First, stress biomarkers in the baseline sample were compared to biomarker levels from a community sample. Second, relationships between depressive symptoms and biomarkers were examined, and, finally, relationships between RPE and biomarkers were analyzed, controlling for demographics, depressive symptoms, and physical functioning. Results: As expected, inflammatory markers and stress hormones were higher in our sample with MDD compared to community participants. In the current sample, however, depressive symptoms were largely unrelated to stress biomarkers, and were unexpectedly inversely related to proinflammatory cytokine levels (TNF-α, IL-1β). Likewise, while RPE were largely unrelated to stress biomarkers, they were related to the anti-inflammatory cytokine IL-1RA and the stress hormone norepinephrine in expected directions. Unexpectedly, RPE were also positively related to the proinflammatory cytokine IFN-γ and to IFN-γ/IL-4 and IFN-γ/IL-10 ratios. Conclusions: Little evidence was found for a consistent pattern of relationships between depressive symptoms or religiosity and stress biomarkers. Of the few significant relationships, unexpected findings predominated. Future research is needed to determine whether religious interventions can alter stress biomarkers over time in MDD.

Highlights

Depressive disorder and religious involvement are common in persons with chronic medical illness
Depression is often accompanied by physiological changes that can adversely affect the course of medical illness over time, including increased levels of pro-inflammatory cytokines, decreased levels of anti-inflammatory cytokines, and increased stress hormones
If any consistent pattern was found in these relationships, religious activities and attitudes were related to higher levels of pro-inflammatory markers, the exact opposite of our hypothesis. This is one of the first studies to provide a detailed examination of associations between religious practices/experiences and a wide range of stress biomarkers in persons with major depressive disorder and chronic medical illness, while controlling for demographics, depressive symptoms and physical functioning

Summary

Introduction

Depressive disorder and religious involvement are common in persons with chronic medical illness. Certain immune elements (such as pro-inflammatory cytokines) can lead to sickness behaviors that resemble depression, which has led to the possibility that altered immune and endocrine functions may be etiologically related to depression, especially when it develops in a setting of chronic stress [16]. Religious practices/experiences (RPE) may produce positive physiological changes in patients with major depressive disorder (MDD) and chronic medical illness. (2014) Religious Involvement, Inflammatory Markers and Stress Hormones in Major Depression and Chronic Medical Illness. Depressive symptoms were largely unrelated to stress biomarkers, and were unexpectedly inversely related to proinflammatory cytokine levels (TNF-α, IL-1β). While RPE were largely unrelated to stress biomarkers, they were related to the anti-inflammatory cytokine IL-1RA and the stress hormone norepinephrine in expected directions.

Results

Discussion

Conclusion