Can Pulmonary Function Testing Predict the Functional Outcomes of Poststroke Patients?: An Observational Study

Patients with stroke may experience pulmonary dysfunction that reduces movement of the muscles involved in postural control and respiration. This study aimed to evaluate the relationship between postural control and respiratory muscle strength using pulmonary function testing. We sought to identify the respiratory function parameters that predict the functional outcomes patients with stroke at discharge.

We prospectively recruited 52 patients with first-ever stroke within 6 mos of onset. Peak cough flow, maximal inspired pressure, maximal expired pressure, forced vital capacity, and forced expiratory volume in 1 sec were measured at baseline and after 4 wks of rehabilitation. The primary outcomes were trunk balance measured using the Trunk Impairment Scale and functional outcomes measured using the Berg Balance Scale and functional independence measure.

The initial peak cough flow, forced vital capacity, and forced expiratory volume in 1 sec values correlated with the Trunk Impairment Scale scores at admission; only the initial peak cough flow and forced vital capacity were predictive factors for the final Trunk Impairment Scale score. Multivariable linear regression analysis showed that the initial peak cough flow was a significant predictive factor for follow-up test scores at discharge: Berg Balance Scale (P < 0.001) and functional independence measure (P < 0.025).

Initial respiratory function was significantly correlated with trunk balance and the functional outcomes.