35% Carbon dioxide and breath-holding challenge tests in panic disorder: a comparison with spontaneous panic attacks
Article first published online: 9 MAR 2006
© 2006 Wiley-Liss, Inc.
Depression and Anxiety
Volume 23, Issue 4, pages 236–244, 2006
How to Cite
Nardi, A. E., Valença, A. M., Mezzasalma, M. A., Lopes, F. L., Nascimento, I., Veras, A. B., Freire, R. C., de-Melo-Neto, V. L. and Zin, W. A. (2006), 35% Carbon dioxide and breath-holding challenge tests in panic disorder: a comparison with spontaneous panic attacks. Depress. Anxiety, 23: 236–244. doi: 10.1002/da.20165
- Issue published online: 19 JUN 2006
- Article first published online: 9 MAR 2006
- Manuscript Accepted: 28 OCT 2005
- Manuscript Revised: 9 AUG 2005
- Manuscript Received: 31 MAR 2005
- Brazilian Council for Scientific and Technological Development (CNPq). Grant Number: 554411/2005-9
- panic attacks;
- anxiety disorder;
Respiration and its control mechanisms may represent an important system involved in abnormal anxiety. Our aim was to compare the demographic and clinical features of patients with panic disorder (PD) with agoraphobia (DSM-IV) who had a panic attack after both the 35% carbon dioxide (CO2) test and the breath-holding test (CPA group), and compare them with PD patients who did not have a panic attack after both tests (NPA group). We examined 76 patients with PD who were administered a 35% CO2test and a breath-holding test within a 1-week interval. Anxiety scales were applied before and after each test. A panic attack was induced in 50 (65.8%) patients during the CO2test (χ2 = 28.44, df = 1, P<.001) and in 40 (52.6%) patients during the breath-holding test (χ2 = 15.35, df = 1, P = .036). All patients who had a panic attack during the breath-holding test also had a panic attack during the CO2test (n = 40; CPA group). Twenty-six (34.2%) patients with PD did not have a panic attack after both respiratory tests (NPA group). The CPA group had more (χ2 = 21.67, df = 1, P = .011) respiratory PD subtype. In the CPA group, the disorder started earlier (Mann–Whitney, P<.001), had a higher familial prevalence of PD (χ2 = 18.34, df = 1, P = .028), and had more previous depressive episodes (χ2 = 23.59, df = 1, P<.001). Our data suggest that there is an association between respiratory PD subtype and the response to respiratory challenge tests: CO2and breath-holding. The CPA may be confirmed as a subgroup of respiratory PD subtype. Depression and Anxiety 23:236–244, 2006. © 2006 Wiley-Liss, Inc.