Association between lung function with postural balance and falls in individuals with moderate to very severe COPD: a cross sectional study and follow up

<bold>Background:</bold> Individuals with chronic obstructive pulmonary disease (COPD) have worse postural balance and higher fall risk. However, the association between lung function and these outcomes is poorly known. <bold>Aim:</bold> To investigate the association between lung function with postural balance and falls in individuals with moderate to very severe COPD. <bold>Methods:</bold> Were assessed pulmonary function test (body plethysmography) and postural balance (force platform). The center of pressure (COP) was quantified in the force platform in a neutral position at rest and after physical exertion (4 to 7 on the Borg Scale). Falls were assessed three months after the assessment. <bold>Results:</bold> Sixty-one individuals with moderate to very severe COPD (67±7 years; FEV1 45±15%pred; residual volume, RV 200±78%pred; carbon monoxide DLCO 70±24%pred) were included. At rest, the anteroposterior (AP) COP displacement showed a weak association with DLCO (r= 0.34, p<0.01). After physical exertion, AP-COP displacement showed a weak association with DLCO (r=0.31, p=0.01) and air trapping (RV%pred; r=0.35, p<0.01). Nineteen individuals (31%) experienced at least one fall during the follow-up period, and no significant differences were observed between fallers (n=19) and non-fallers (n=42) regarding age, lung function, and postural balance. However, after exertion, only fallers presented a strong association between AP-COP displacement with RV (r=0.79, p<0.001) and DLCO (r=0.63, p<0.001). Nevertheless, RV was the only independent outcome associated with falls. <bold>Conclusion:</bold> Our findings suggest tha air trapping is associated with falls in moderate to severe COPD individuals.