Background respiratory morbidity is common in patients with sickle cell anaemia (SCA). The quality of care and environmental factors might have an influence on their respiratory health.

Aims to compare spirometry lung function in children and adolescents attending sickle cell centres in UK and Italy.

Methods anthropometry and spirometry were undertaken in SCA-patients (SS,Sb⁰) aged 6–17 years. Exclusion criteria: SCArelated morbidity within the last two weeks and inability to perform an adequate spirometry. Portable spirometers (Pony FX, Cosmed-IT, Easy-on PC, NDD-CH) were used. Z-scores of anthropometric and spirometric data were derived, respectively, from CDC2000 and GLI-black equation (Quanjer, ERJ2012). Spirometry patterns were classified as normal, obstructive (zFEV₁/FVC < 1.64) or restrictive (zFVC < 1.64 +zFEV₁/ FVC ³ 1.64). Differences between groups were assessed by ttests and considered statistically significant for p values<0.05.

Results Eighty-five subjects of African ancestry were included (n.46 UK; n.39 Italy; 42% girls; age-range: 6.2–17.9 years). Prevalence of obstructive pattern was higher in SCA-patients from UK, while a restrictive pattern was more common in subjects living in Italy (table). Mean FEV1/FVC was ~0.6 z-scores lower in SCA patients from UK (p<0.01). Age was negatively correlated (p<0.05) with both zFEV1(R² 0.19) and zFVC(R² 0.136).

Conclusion obstructive lung disease is more common among paediatric subjects with SCA living in UK than in Italy. Differences in the level of ambient air pollution and prevalence of allergies, could have contributed to these findings. It seems that SCA patients from Italy develop earlier a restrictive picture. These results need further confirmation.