Perceived control and immune and pulmonary outcomes in children with asthma.

OBJECTIVE This study tested the relationships between perceived control and biological processes relevant to asthma in children. METHODS Forty children diagnosed with asthma completed the Children's Health Locus of Control (CHLC) scale. Participants also completed pulmonary function testing, measuring forced vital capacity (FVC), and forced expiratory volume in 1 second (FEV1). Blood was drawn to assess immune markers associated with asthma. Specifically, stimulated production of the cytokines interleukin 4 (IL-4), interleukin-5 (IL-5), interleukin-13 (IL-13), interferon-gamma (IFN-gamma), as well as eosinophil count, was measured. At home, participants completed peak expiratory flow rate (PEFR) measures to monitor their daily pulmonary function. RESULTS Higher levels of perceived control were associated with significantly better FVC, FEV1, and PEFR variability. Higher levels of perceived control were also associated with decreased production of asthma-related cytokines, including IL-4, IL-5, and IL-13. CONCLUSION These results suggest that psychological processes such as perceived control may play an important role in asthma-related biological processes among children with asthma.