Anxiety sensitivity and trait anxiety are associated with response to 7.5% carbon dioxide challenge.

Meg E Fluharty,Marcus R Munafò,Angela S Attwood

doi:10.1177/0269881115615105

Meg E Fluharty, Marcus R Munafò + Show 1 more

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https://doi.org/10.1177/0269881115615105

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Abstract

The 7.5% carbon dioxide (CO2) inhalation model is used to provoke acute anxiety, for example to investigate the effects of anxiety on cognitive processes, or the efficacy of novel anxiolytic agents. However, little is known about the relationship of baseline anxiety sensitivity or trait anxiety (i.e., anxiety proneness), with an individual’s response to the 7.5% CO2 challenge. We examined data from a number of 7.5% CO2 challenge studies to determine whether anxiety proneness was related to subjective or physiological response. Our findings indicate anxiety proneness is associated with greater subjective and physiological responses. However, anxiety-prone individuals also have a greater subjective response to the placebo (medical air) condition. This suggests that anxiety-prone individuals not only respond more strongly to the 7.5% CO2 challenge, but also to medical air. Implications for the design and conduct of 7.5% CO2 challenge studies are discussed.

Highlights

The use of hypercapnic gas to provoke anxiety or panic responses, in both patient and healthy volunteers, has a long history in psychiatric research
We examined data from a series of 7.5% CO2 challenge studies in order to determine whether there is an association between anxiety proneness and a range of subjective and physiological responses
We predicted that anxiety proneness would be associated with a stronger response in both conditions, and we were interested in whether the magnitude of this response differed between the two conditions, and whether these relationships were stronger for measures of anxiety sensitivity or trait anxiety

Summary

Introduction

The use of hypercapnic gas to provoke anxiety or panic responses, in both patient and healthy volunteers, has a long history in psychiatric research. Many studies use the 7.5% carbon dioxide (CO2) challenge to induce an acute anxiety response experimentally, which produces symptoms similar to those associated with Generalised Anxiety Disorder (Bailey et al, 2005). This has been shown to increase subjective and physiological indices of state anxiety reliably (Bailey et al, 2005). High trait anxiety and anxiety sensitivity are associated with subjective response during voluntary hyperventilation studies, despite similar levels of autonomic arousal (Whittal and Goetsch, 1995; Whittal et al, 1994). We predicted that anxiety proneness would be associated with a stronger response in both conditions, and we were interested in whether the magnitude of this response differed between the two conditions, and whether these relationships were stronger for measures of anxiety sensitivity or trait anxiety

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