ObjectiveWe investigated the modulation of pulmonary function by mood states in the daily life of asthmatic patients and nonasthmatic control subjects and its relationship to the airway effects of laboratory induction of emotion using films.MethodsTwenty asthmatic patients and 20 nonasthmatic control subjects participated in a laboratory session in which various emotions (ie, anxiety, anger, depression, happiness, elation, contentment, and neutrality) were induced by films. Respiratory resistance (Ros) was measured by forced oscillation. After this session, participants kept mood diaries, including regular spirometric self-assessments, for at least 3 weeks. Episodes of strong negative or positive mood were selected from these diaries and compared with conditions of relative affective neutrality.ResultsIn asthmatic patients, negative mood states, and to a lesser degree positive mood states, were associated with a reduction in forced expiratory volume in the first second (FEV1) compared with neutral states. These effects were not observed in nonasthmatic control subjects. Self-reports of arousal varied in a reciprocal manner with FEV1, whereas physical activity did not vary systematically between mood episodes. A moderate negative relationship between changes in FEV1during negative mood episodes and changes in Rosduring viewing of the depressing film was also observed in asthmatic patients.ConclusionPulmonary function of asthmatic patients is negatively affected by strong mood states in daily life. Airway effects of negative emotion induction, particularly depression, can predict changes in pulmonary function in response to negative mood in the field.