Panic disorder respiratory subtype: psychopathology and challenge tests – an update

Abstract

Panic disorder (PD) pathophysiology is very heterogeneous, and the discrimination of distinct subtypes could be very useful. A subtype based on respiratory symptoms is known to constitute a specific subgroup. However, evidence to support the respiratory subtype (RS) as a distinct subgroup of PD with a well-defined phenotype remains controversial. Studies have focused on characterization of the RS based on symptoms and response to CO 2 . In this line, we described clinical and biological aspects focused on symptomatology and CO 2 challenge tests in PD RS. The main symptoms that characterize RS are dyspnea (shortness of breath) and a choking sensation. Moreover, patients with the RS tended to be more responsive to CO 2 challenge tests, which triggered more panic attacks in this subgroup. Future studies should focus on discriminating respiratory-related clusters and exploring psychophysiological and neuroimaging outcomes in order to provide robust evidence to confirm RS as a distinct subtype of PD.How to cite this article: Okuro RT, Freire RC, Zin WA, Quagliato LA, Nardi AE. Panic disorder respiratory subtype: psychopathology and challenge tests -an update. Braz J Psychiatry. 2020;00:000-000. http://dx.

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