Oliveira, CláudiaVeiga, AnabelaGuimarães, MiguelMartins, Cristiana2023-02-162023-02-162021-12-01http://hdl.handle.net/10400.14/40284Background and Aim of the Study: Obesity is currently one of the biggest social problems and can be assessed using several indicators. The Body Mass Index (BMI) is a simple method to evaluate body fatness. Thus, the effects of BMI on the respiratory system have been increasingly studied in the field of pneumology. The main objective of this work was to verify if there is an influence of BMI on the strength of the respiratory muscles and spirometric parameters. Material and Methods: This study was conducted using a sample that consisted of 374 individuals. For that, the clinical processes of patients who underwent preoperative assessment were consulted and divided according to different BMI classes. The data was analyzed in an encrypted database IBM SPSS Statistics software. Results: The results obtained showed that there are significant statistically differences between maximal inspiratory pressure (MIP) (p-value <0.001, p-value <0.001, p-value= 0.006, for gender, age and BMI, respectively), for maximal expiratory pressure (MEP) (p-value <0.001 for gender and p-value = 0.001 for BMI), for forced expiratory volume in one second (FEV1) (p-value =0.018 for gender), for forced expiratory volume (FEV) (p-value = 0.006 for gender, p-value = 0.005 for BMI) and FEV1/FVC relation (p-value <0.001, age). A negative correlation between BMI and MIP was evidenced. Moreover, the gender of the patient influences the variables studied since women have higher values of MIP and men of MEP. Conclusions: The current study is the first to address the relationship between BMI, spirometry tests and respiratory muscle strength in Portugal.engBody mass indexMaximal inspiratory pressureMaximal expiratory pressureSpirometryObesityjournal article