Hyperventilation syndrome: an elegant but scientifically untenable concept

Abstract

The concept of hyperventilation and the principle of a vicious circle provide an elegant explanation for the development of a wide range of somatic and psychological symptoms, the so-called hyperventilation syndrome (HVS). The model has a high degree of credibility and has led to the development of therapeutic interventions that appeared beneficial. However, recent investigations dismiss hyperventilation as an important symptom-producing mechanism. First, the hyperventilation provocation test appears to be invalid as a diagnostic test. Second, studies using ambulant monitoring of pCO₂ demonstrate that the vast majority of real-life attacks are not attended by decreases in pCO₂. Third, the evaluation of therapy outcome studies indicate that the beneficial effect of breathing retraining is probably not mediated by reducing the tendency to hyperventilate. We conclude that a diagnosis of HVS should be avoided.