Longitudinal assessment of lung function in children with sickle cell disease

Objectives: To prospectively assess longitudinal lung function in children with sickle cell disease (SCD). Working hypothesis: Lung function in SCD children deteriorates with increasing age and the decline is more marked in younger children who have recently suffered ACS episodes. Study design: Two prospective longitudinal studies. Patient-subject selection: Two cohorts of SCD children and age and ethnic matched controls were recruited. Cohort One (47 SCD and 26 controls) had a median age of 8.8 years and follow up of 2 years and Cohort Two (45 SCD and 26 controls) a median age of 10.2 years and follow up of 10 years. Methodology: Forced expiratory volume in one second (FEV₁), vital capacity (VC), forced expiratory flow between 25% and 75% of VC (FEF _25-75), total lung capacity (TLC) and residual volume (RV) were measured on two occasions. Results: In both groups of SCD children, lung function declined significantly, but in neither control group. ACS episodes were more frequent during the follow up period in Cohort One than Cohort Two (P1 (P=0.008), VC (P=0.001), FEF_25-75 (P=0.030), TLC (P=0.004), and RV (P=0.043). In Cohort Two restrictive abnormalities were more common at follow up (P=0.006). Conclusions: Lung function deteriorated with increasing age in SCD children and the rate of decline was greater in younger children in whom ACS episodes were more common. Pediatr Pulmonol.