Physical activity, sex differences, and functional exercise capacity in bronchiectasis: Insights from a South Asian cohort.

Abstract

Bronchiectasis causes breathlessness and fatigue, reducing quality of life. Many affected individuals are less active than healthy peers, increasing their risk of exacerbations and hospitalizations. Correlates of physical activity (PA) and functional exercise capacity remain inconsistent, and most evidence comes from Western populations. Sex-specific differences in disease presentation and functional outcomes are recognised yet remain underexplored in South Asian cohorts. The aim of the study was to examine the relationship between PA and demographic, clinical, and functional variables; to compare these characteristics between sexes; and to identify predictors of functional exercise capacity in individuals with bronchiectasis. Fifty-five adults with stable bronchiectasis were assessed using the International Physical Activity Questionnaire for PA, the modified Medical Research Council scale (mMRC) for dyspnoea, the six-minute walk distance (6MWD) for functional exercise capacity and the bronchiectasis health questionnaire (BHQ) for health status. Bronchiectasis-related clinical characteristics, including disease severity, exacerbation frequency, microbiological status, radiological severity, and disease duration were also recorded. Associations and predictors were examined using correlation analyses and multivariate regression. Lower PA was associated with greater dyspnoea severity (rs = -0.344) and shorter disease duration (rs = 0.275). Females had shorter absolute walking distance (≈57 metres shorter 6MWD) but no significant difference in % predicted 6MWD compared with males. Females also reported higher PA (+1350 MET-minutes/week) than males. Reduced 6MWD correlated with older age, lower BHQ score, female sex, increased exacerbation frequency, greater dyspnoea severity and higher radiological severity. Dyspnoea severity and radiological severity independently predicted functional exercise capacity. Lower PA was weakly associated with greater dyspnoea severity and shorter disease duration. Females reported higher self-reported PA levels despite shorter absolute walking distances than males. Dyspnoea severity emerged as the strongest predictor of functional exercise capacity, while radiological severity was also associated with reduced 6MWD.