Relationship between cough strength and functional level in elderly.

BACKGROUND Respiratory muscle strength is influenced by aging. OBJECTIVES To assess, in a healthy elderly population, the influence of physical activity and functional performance on the pulmonary function parameters, on respiratory muscle strength and on coughing. METHODS Observation study that sixty one elderly with age equal or more than 60 years (72.3 ± 7.2 years), with normal spirometry were included. Maximal Inspiratory Pressure (MIP), Maximal Expiratory Pressure (MEP), Peak Expiratory Flow (PEF), Peak Cough Flow (PCF) and Human Activity Profile (HAP) were evaluated. The elderly were separated in two groups (active and moderately active) according to HAP. Student`s test was used for univariate analysis and regression analysis models was used for multivariate analysis. RESULTS Elderly participants who were classified as active presented on average 13.5 cmH₂O higher MEP (88 ± 21.4 cmH₂O), and 16.2 cmH₂O higher MIP (76 ± 17.7 cmH₂O). Maximal respiratory pressure decreases 1 cmH₂O per year. The PEF and PCF were higher for male (p < 0.001) and active elderly (p = 0.046 e p = 0.004 respectively). A positive correlation was observed between HAP and the following variables: MEP MIP and PCF (r = 0.527, p < 0.001; r = 0.498, p < 0.001 and r = 0.365, p = 0.004, respectively). CONCLUSIONS The active life style can positively affect the respiratory muscle strength and PCF values. Aging is associated to respiratory muscle strength reduction (both inspiratory and expiratory). Women showed lower PEmax.