Psychosomatic symptoms and breathing pattern

Abstract

Objective: Study of the links between breathing pattern, negative affectivity, and psychosomatic complaints at rest and following hyperventilation. Methods: In 819 patients with anxiety and somatoform disorders and 159 healthy subjects, self-reported symptoms, breathing pattern, and end-tidal CO 2 concentration (FetCO 2) were recorded during rest and following a hyperventilation provocation test (HVPT). The relationship between disorder category, symptoms, age, and score of STAI-trait (as a measure of negative affectivity) on the one hand, and breathing pattern on the other was investigated, separately in men and women. Results: Anxiety disorders, and to a lesser extent, somatoform disorders, were characterized by breathing instability (progressive decrease of FetCO 2 at rest during mouthpiece breathing, delayed recovery of FetCO 2 following HVPT), the mean values of respiratory frequency, and FetCO 2 being modulated by STAI-trait. After grouping the symptoms into independent factors, links were observed between symptoms and breathing pattern, independently from the presence of an anxiety or somatoform disorder. Conclusion: Some symptom factors appeared to be related to a lower FetCO 2 during hyperventilation, others likely directly influenced the breathing pattern. Among those, mainly respiratory symptoms were accompanied by a reduction of FetCO 2 at rest, with slower recovery of FetCO 2 following HVPT. The latter was observed also in the presence of marked anxiety. In contrast, subjects complaining of dizziness, fainting, and paresthesias in daily life presented higher values of FetCO 2 following HVPT, probably due to a voluntary braking of ventilation during HVPT.