Stress and anxiety: counterpart elements of the stress/anxiety complex.

The relationship between stress and anxiety is complicated. Stress initially arises from one's environment; anxiety overlays physiological arousal, cognitive appraisals, emotional states, and behavioral responses. Both are components of a stress-anxiety complex, which has evolved to enable individuals to adapt to their environment and achieve equilibrium. Anxiety disorders, which result when this mechanism goes awry, occur along a spectrum. One of the main variables affecting anxiety disorders is the extent of stress. Each anxiety disorder should be evaluated along a stress axis, leading to improved case conceptualization and intervention strategies.