Characteristics of postural control among young adults with asthma

Objective: We investigated whether young adults with asthma have impaired balance and whether this impairment is related to altered musculoskeletal function and/or psychological characteristics. Methods: 21 participants with a self-reported asthma diagnosis but no known postural instability or history of falls, and 18 control participants were recruited from undergraduate psychology courses. Participants performed a postural control task of maintaining the center of pressure (COP) in a fixed position with visual feedback (feedback condition) and while standing as still as possible without visual feedback (no-feedback condition). COP variability, regularity and task performance were used to characterize the quality of balance. To document group differences in musculoskeletal function, we measured neck and lower back angles as well as range of motion (ROM) of the neck in the frontal and sagittal planes. To document group differences in psychological state, we administered self-report questionnaires to assess symptoms of anxiety and depression, anxiety sensitivity and negative effect. Results: COP variability and task performance were similar between the groups, but participants with asthma exhibited more regular anterior-posterior COP dynamics. Participants with asthma had smaller ROM of neck extension, a more forwardly bent neck, greater thoracic spine angle, and they reported greater levels of the physical concerns facet of anxiety sensitivity. These musculoskeletal and affective variables moderated COP differences between the groups. Conclusions: Young adults with asthma showed a different postural control strategy in the absence of any obvious balance impairment. This change in strategy is related to musculoskeletal and affective characteristics of individuals with asthma.