Impact of Cardiovascular Disease on dyspnea and lung function in a population of Tunisian smokers without airflow limitation

Introduction: It is well known that cardiovascular and respiratory systems are closely linked with each other in physiology and pathophysiology. However, their association in smokers without airflow limitation has not been clearly defined. Aim of study: We aimed to evaluate the impact of cardiovascular disease (CVD) on respiratory function and dyspnea in a population of smokers without airflow limitation. Methods: We retrospectively analyzed 520 records of smoking men who underwent spirometry between 2016 and 2020. Study population were divided into 2 groups of smokers: G1 without CVD (n=396) and G2 with CVD (n=124). Data of demographic characteristics (age, BMI), tobacco consumption (PY), lung function (FEV1%, FVC%) and modified Medical research council dyspnea scale (mMRC) were compared between G1 and G2. Results: The mean age (years old) was 55 ± 6 for G1 and 56 ± 6 for G2. No significant difference has been noted between G1 and G2 when compared BMI and tobacco consumption. However, G2 had a higher mMRC (G1: 1.2 ± 0.9 vs G2:0.8 ± 0.8; p=0.001) and lower FEV1% (G1: 94.5 ± 11.8 vs G2: 91.2 ± 12.1; p= 0.007) and FVC% (G1: 95.3 ± 12.9 vs G2: 89.9 ± 12.5; p< 0.001) compared to G1. Conclusion: Despite the absence of airflow limitation in baseline spirometry, our data confirm the inverse relationship between CVD and lower values of FVC and FEV1 in smokers population. An early healthcare intervention on lifestyle could be useful to reduce the decline of pulmonary function.