Journal of Depression and Anxiety
Open Access

Abstract

Anxiety Chronicity and Psychiatric Comorbidity:Influences on Salivary Alpha-Amylase in a Diagnostically Heterogeneous Sample of Outpatients with Anxiety Disorders

David J Finitsis, Dean G Cruess, Giselle K Perez, Olivia E Bogucki, and David F Tolin

Anxiety disorders are the most prevalent class of mental disorders, often characterized by a chronic course and comorbid psychopathology. Reports of anxiety-cortisol relationships are inconsistent in the literature. Salivary alphaamylase (sAA), a biomarker of autonomic nervous system activation, provides an opportunity to examine the stress response more fully. This study recruited a diagnostically  heterogeneous outpatient sample attending a specialized anxiety treatment center to explore  relationships between trait anxiety and salivary stress biomarkers and tested the influence of symptom chronicity and psychiatric comorbidity on this relationship. Multiple regression analyses were conducted to examine associations between psychosocial and physiological variables. Forty-four adults completed
study procedures. Univariate associations were detected between chronicity and cortisol (r= -0. 348; p= 0. 028) and between comorbidity and sAA(r=0. 381; p= 0. 026). Although the statistical significance of these associations at α=0. 05 was lost when multiple regression was used to control for covariates, the relationship between comorbidity and sAA retained its strength of association (β=0. 341; p=0. 075). Chronicity moderated the anxiety-stress relationship such that greater chronicity significantly  strengthened the relationship between trait anxiety and sAA; this interaction accounted for a significant proportion of the observed variance (ΔR2=0. 469; p = 0. 001). This exploratory study supports the  feasibility of sAA in anxiety-stress research using diagnostically heterogeneous samples. This work also suggests that the factors of symptom chronicity and psychiatric comorbidity may contribute variance to the anxiety-stress relationship in typically presenting anxiety disorder samples. Further research is needed to replicate the utility of alpha amylase in ecologically valid samples demonstrated here and understand in greater detail how these highly prevalent characteristics of anxiety may influence autonomic activation.