FOREARM BLOOD FLOW IN NORMAL SUBJECTS AND PATIENTS WITH PHOBIC ANXIETY STATES

Systemic hormonal and physiological abnormalities in anxiety disorders

Among the studies of systemic hormonal and physiological abnormalities associated with anxiety disorders, the most consistent and extensive findings suggest (a) peripheral adrenergic hyperactivity (including increases in norepinephrine but not epinephrine) and functional dysregulation, (b) increased incidence of mitral valve prolapse in panic patients, and (c) normal suppressibility of the hypothalamic-pituitary-adrenal cortical endocrine system with dexamethasone in panic patients. Other less-certain findings include (a) increased circulating concentrations of plasma ACTH and/or cortisol, and prolactin, in panic patients, (b) increased platelet monoamine oxidase activity in generalized anxiety and/or panic patients, (c) decreased gonadal axis activity in some anxious individuals, (d) decreased nighttime melatonin plasma concentrations in panic patients, and (e) peripheral alpha 2 and beta-adrenoreceptor down-regulation, with normal serotonin binding parameters. These findings, taken together, provide tentative support for dysfunction in adrenergic and GABAergic central nervous system mechanisms in people with anxiety disorders. Abnormal anxiety and normal stress both show evidence of adrenergic hyperactivity; however, there appear to be differences in hormonal profiles, especially the apparent lack of increase of epinephrine during panic attacks, as well as differences in the reactivity of the system, and in the "trigger" mechanisms which determine when the response occurs.

Forearm blood flow and phobic anxiety

The measurement of muscle blood flow using occlusive plethysmography has recently been proposed as an objective index of anxiety (Harper et al., 1965; Kelly, 1966, 1967). Although the method has been used by physiologists for many years, and its sensitivity to psychological stress has often been mentioned as an incidental finding in physiological studies, its application in psychiatric or psychological research has been slow to develop, perhaps because rather cumbersome apparatus is required. However, promising results were reported by Kelly (1966), who differentiated patients suffering from anxiety states from mixed neurotic patients and normal controls, and who showed changes after leucotomy in anxious patients.

The relationship between clinical diagnosis and anxiety, assessed by forearm blood flow and other measurements

Anxiety may be present to a greater or lesser degree in almost every psychiatric syndrome. The ability to quantify the degree of anxiety present in an individual patient has important implications for diagnosis, treatment and prognosis. Accurate clinical assessment of anxiety is by no means an easy task, although many psychiatrists believe it to be. If no other methods are used, there is no way of knowing how often an individual clinician is right or wrong. However, if several independent methods of assessing anxiety are used, more data are available, and a better overall judgment on an individual patient can be made.