Spirometry profiles of overweight and obese individuals with unexplained dyspnea in Saudi Arabia

Background: Obesity is a common cause of dyspnea. However, the impacts of obesity on spirometry parameters, particularly among individuals with unexplained dyspnea, have not been well investigated. Objectives: This study aimed to explore the prevalence of overweight and different classes of obesity and their effect on spirometry parameters among subjects with unexplained dyspnea in Saudi Arabia. Methods: We conducted a retrospective electronic medical record review of individuals with unexplained dyspnea who visited our pulmonary clinic between January 2016 and December 2022 and assessed the association of body mass index (BMI) with spirometry parameters. After we classified the subjects based on their BMI values, we determined the impacts of increased BMI on spirometry parameters. Results: The sample included a total of 978 subjects with unexplained dyspnea. The prevalence of overweight and obesity among our study sample was high (33 % and 47 %, respectively). All spirometry parameters: forced vital capacity (FVC) L, forced expiratory volume in 1 s (FEV1) L, forced expiratory flow at 25–75 % (FEF 25–75 %) L/sec and peak expiratory flow (PEF) L/sec were significantly lower in obese individuals with dyspnea compared to normal weight subjects. In addition, our findings showed a negative correlation between BMI and FVC, FEV1, FEF 25–75 %, and PEF. Conclusion: The high prevalence of obesity and overweight and the impairment of lung function because of high body weight among subjects with dyspnea point to the need for routine assessment and the evaluation of nutritional status in primary health care facilities for early intervention.