The impact of recurrent acute chest syndrome on the lung function of young adults with sickle cell disease

The aim of this study was to assess the impact of recurrent acute chest syndrome (ACS) episodes on the lung function of young adults with sickle cell disease (SCD). Our prospective study included 80 SCD adults [26 with recurrent acute chest syndrome (ACS)] and 80 ethnically matched controls aged between 18 and 28 years. Lung function (spirometry and lung volumes) was measured and the results were expressed as the percentage predicted for height. Bronchial hyperresponsiveness (BHR) was assessed by the response to either a bronchodilator or an exercise challenge. The adults with recurrent ACS (two or more ACS episodes) had lower median forced vital capacity (74 vs. 83%, p = 0.03), forced expiratory volume in 1 s (79 vs. 90%, p <0.03), and total lung capacity (69 vs. 81%, p = 0.04) than SCD adults who had one or no ACS episodes. The greater the number of ACS episodes, the greater the reduction in lung function (p = 0.001). The adults with SCD had lower median forced vital capacity (81 vs. 106%), forced expiratory volume in 1 s (85 vs. 107%), and total lung capacity (80 vs. 87%) than the controls (p <0.001). Similar numbers in each group had BHR (p = 0.2). The prevalence of restrictive ventilatory defect in the patients with SCD was almost double that of the controls (p = 0.004). Young adults with SCD have worse lung function than ethnically matched controls, particularly if they have suffered recurrent ACS episodes.