Correlation between body mass index and pulmonary function indexes in patients with bronchial asthma and suggestions for patient management / 中华健康管理学杂志

ABSTRACT

Objective:To analyze the correlation between body mass index (BMI) and lung function in patients with bronchial asthma (asthma).Methods:This study was a retrospective study. A total of 828 patients with asthma were included from March 2013 to November 2022 in the first affiliated Hospital of Guangxi Medical University, including 292 males and 536 females, aged 21-82 years, with a median age of 47 years. According to BMI, these asthma patients were divided into high BMI group (BMI≥24 kg/m 2), normal BMI group (18.5 kg/m 2≤BMI<24 kg/m 2) and low BMI group (BMI<18.5 kg/m 2). Forced vital capacity (FVC), forced expiratory volume in first second (FEV 1), FEV 1/FVC, maximum mid-expiratory flow (MMEF), forced expiratory flow at 25%, 50% and 75% of FVC (FEF 25%, FEF 50%, FEF 75%), peak expiratory flow (PEF), absolute increases in measured values of FVC and FEV 1 and percentage increases in FVC%pred (“%pred” represents the percentage of related indicators to expected value) and FEV 1%pred after inhalation of bronchodilator (salbutamol) were measured by pulmonary function meter. The correlation between BMI and the above indexes was analyzed. Results:In the high BMI group, FEV 1%pred, MMEF, FEF 25%, FEF 50% and FEF 75% were significantly lower than those in the normal BMI group and the low BMI group (all P<0.05), FVC% pred was significantly lower than those in the normal BMI group( P<0.05), and the percentage increase of FEV 1%pred was significantly lower than those in low BMI group ( P<0.05). FVC% pred in the normal BMI group was significantly higher than that in the low BMI group ( P<0.05). In male patients, BMI was negatively correlated with the absolute increase of FEV 1 ( r=-0.148, P<0.05); In female patients, BMI was negatively correlated with FEV 1%, FEV 1/FVC, MMEF, FEF 25%, FEF 50%, FEF 75% and the percentage increase of FEV 1%pred ( r=-0.124, -0.127, -0.165, -0.138, -0.156, -0.162, -0.106, all P<0.05). Conclusion:There is a significant correlation between BMI and lung function in patients with asthma, and the lung function in patients with high BMI is relatively worse; and in female patients, the effect of BMI on lung function is more significant; the increase of BMI can lead to the decrease of lung function and airway reversibility, suggesting that attention should be paid to the management of BMI in asthma management.