Mood states associated with transitory changes in asthma symptoms and peakexpiratory flow

Objective: This study examined the within-person relations between transito ry changes in mood, asthma symptoms, and peak expiratory flow rate (PEFR). Methods: Thrice-daily for 21 consecutive days, 48 adults with moderate to s evere asthma entered information in palm-top computers about their mood and asthma symptoms. A multidimensional model of mood, ie, the mood circumplex , informed the assessment of mood arousal and mood pleasantness. At each ob servation, participants also recorded their PEFR with peak flow meters that stored blinded data. Albuterol doses were also monitored electronically. B efore and after the 21-day study, spirometric measures of airways obstructi on were taken under controlled conditions. Results: Random effects regressi on models revealed a significant, but weak, within-person relation between symptoms and PEFR. Changes in mood vectors with an arousal component were s ignificantly related to PEFR changes, whereas changes in mood vectors with a pleasantness component tracked changes in asthma symptom reports, even af ter adjustment for contemporaneous PEFR and after controlling for time of d ay and albuterol dosing. Comparison of spirometric assessments with unsuper vised PEFR suggested that part of the relation between mood arousal and PEF R may be attributable to the "effort-dependence'' of peak flow self-monitor ing. Conclusions: Different dimensions of mood were associated with transit ory changes in asthma symptoms and PEFR. This may be one reason why individ uals with asthma misperceive the severity of their symptoms in relation to underlying airways obstruction.