[Evolution over time in over perceivers of dyspnea in asthma].

OBJECTIVE

In previous studies we identified a subgroup of patients whose perception of breathlessness was exaggerated during acute bronchoconstriction and who were termed "over perceivers" or "hyperperceivers". In this study we aimed to determine whether such over perception is sporadic or stable over time. We also examined whether there is an association between over perception of dyspnea and hyperventilation syndrome.

PATIENTS AND METHODS

The subjects were 22 stable asthmatics (11 men, 11 women) who had been over perceivers of dyspnea in a study 9 years earlier. After a medical history was taken, a patient performed forced spirometry and a severity classification was made according to the criteria of the Global Initiative for Asthma (GINA). A bronchial histamine challenge was then administered to measure dose-related perception of dyspnea on a Borg scale, according to a procedure that was similar to the one used 9 years earlier by the same investigator. The patients were also asked for a subjective assessment of the severity of their asthma (scale, 0-10) and to respond to items on the Nijmegen hyperventilation questionnaire and the trait form of the State-Trait Anxiety Inventory.

RESULTS

The overall perception of severity of disease, level of anxiety, and perception of dyspnea at rest were lower after 9 years (P<.001). No change was observed in bronchial hyperresponsiveness (dose of inhaled histamine required to provoke a 20% decline in forced expiratory volume in the first second [FEV1]-PD20) or objective parameters of severity (FEV1 and GINA classification). Fourteen asthmatics (64%) were still over perceivers and the other patients had changed: 6 were normal perceivers and 2 were "poor perceivers". Only subjective perception of disease severity improved for the patients who were still over perceivers; the other patients, on the other hand, showed improvements in subjective assessments, objective ones (except PD20), and anxiety. Finally, those who remained over perceivers had higher scores for anxiety (24 vs 15; P<.05) and hyperventilation (18 vs 13; P= not significant).

CONCLUSIONS

Most over perceivers of dyspnea remain so over the years and this trait is related to anxiety. We have been unable to demonstrate an association with hyperventilation syndrome.