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Behavior of respiratory muscle strength in morbidly obese women by using different predictive equations
Eli M Pazzianotto-Forti1, Fabiana S Peixoto-Souza, Camila Piconi-Mendes
1Postgraduate Physical Therapy Program, Universidade Metodista de Piracicaba, Piracicaba, SP, Brasil. empforti@unimep.br
Background:
Studies on the behavior of respiratory muscle strength (RMS) in morbidly obese patients have found conflicting results.
Objectives:
To evaluate RMS in morbidly obese women and to compare the results by using different predictive equations.
Method:
This is a cross-sectional study that recruited 30 morbidly obese women and a control group of 30 normal-weight women. The subjects underwent anthropometric and maximal respiratory pressure measurement. Visual inspection of the Bland-Altman plots was performed to evaluate the correlation between the different equations, with a p value lower than 0.05 considered as statistically significant.
Results:
The obese women showed a significant increase in maximal inspiratory pressure (MIP) values (-87.83±21.40 cmH(2)O) compared with normal-weight women (-72±15.23 cmH(2)O) and a significant reduction of MIP (-87.83±21.40 cmH(2)O) according to the values predicted by the EHarik equation (-130.71±11.98 cmH(2)O). Regarding the obtained maximal expiratory pressure (MEP), there were no between-group differences (p>0.05), and no agreeement was observed between obtained and predicted values of MEP and the ENeder and ECosta equations.
Conclusions:
Inspiratory muscle strength was greater in the morbidly obese subjects. The most appropriate equation for calculating the predicted MIP values for the morbidly obese seems to be Harik-Khan equation. There seem to be similarities between the respiratory muscle strength behavior of morbidly obese and normal-weight women, however, these findings are still inconclusive.
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