Decreased circulating epinephrine, possibly secondary to decreases hypothalamic-adrenal medullary discharge; a supplementary hypothesis of bronchial asthma pathogenesis

Emotions and stress increase respiratory resistance in asthma

OBJECTIVES

Clinical reports suggest that various emotions and types of stress can precipitate asthmatic symptoms, but there is little experimental evidence to substantiate this claim. We studied the impact of different emotional states and stress on respiratory resistance in asthmatic and nonasthmatic individuals.

METHODS

Participants (24 asthmatic and 24 nonasthmatic patients) viewed short film sequences selected to induce anxiety, anger, depression, elation, happiness, contentment, or a neutral affective state and completed two stressful tasks, mental arithmetic to induce active coping efforts and viewing of medical slides to induce passive coping efforts. Oscillatory resistance, heart rate, blood pressure, baroreflex sensitivity, skin conductance level, respiration rate and volume, and self-reported affective state were measured throughout the session.

RESULTS

Uniform increases in oscillatory resistance were found in all emotional states compared with the neutral state and during mental arithmetic in both groups. Asthmatic patients showed stronger reactions to the medical slides than healthy control subjects, with significant increases in oscillatory resistance, blood pressure, skin conductance level, and minute volume, as well as higher levels of self-reported depression, arousal, and shortness of breath. Changes in oscillatory resistance were inconsistently correlated with other physiological indices.

CONCLUSIONS

Various emotional states and stress increase oscillatory resistance largely independently of concurrent increases in autonomic or ventilatory activity. The particular sensitivity of asthmatics to passive coping demand requires additional research.

Changes in serum catecholamine levels during acute bronchospasm

STUDY OBJECTIVES

Previous studies reported that norepinephrine levels increased during acute asthma, while epinephrine levels have remained at normal levels. The purpose of this study was to determine whether the lack of rise in epinephrine levels is due to an inherent defect in catecholamine secretion in asthmatics or is a result of an insufficient stimulus for epinephrine release.

DESIGN

County-owned, university-affiliated emergency department.

SETTING

Prospective study.

TYPE OF PARTICIPANTS

Patients more than 18 years old presenting to the ED with an acute exacerbation of asthma or chronic obstructive pulmonary disease (COPD).

INTERVENTIONS

Initial phlebotomy and spirometry were followed by treatment with either albuterol or albuterol and glycopyrrolate. Asthmatic patients received steroids. Phlebotomy and spirometry were performed again after treatment.

MEASUREMENTS AND MAIN RESULTS

There was no difference in epinephrine levels between patients with asthma and those with COPD either before or after treatment. Norepinephrine levels were higher in patients with COPD, both before and after treatment. There was only a weak correlation between epinephrine levels and pretreatment FEV1 for asthma but not for COPD.

CONCLUSION

Moderate bronchospasm is not a major stimulus for epinephrine release in either acute asthma or COPD.