Sickle-cell disease in Malawian children is associated with restrictive spirometry: a cross-sectional survey

BACKGROUND: A proportion of children with sickle-cell disease (SCD) demonstrate clinical findings consistent with the diagnosis of asthma. These children are at increased risk of complications, including acute chest syndrome. OBJECTIVE: To assess lung function and symptoms of asthma in children with SCD in Blantyre, Malawi. DESIGN: Twenty-five children aged 7–16 years with electrophoretically confirmed SCD were recruited to undergo spirometry and questionnaire screening of asthma symptoms. Forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC) and FEV1/FVC ratio were compared with local and international reference ranges. Symptoms were assessed using the International Study of Asthma and Allergies in Childhood questionnaire. RESULTS: Mean spirometric indices, represented as Z-scores derived from international reference ranges, were low: FEV1 −1.64 (95%CI −2.04 to −1.23), FVC −1.49 (95%CI −1.90 to −1.09), FEV1/FVC −0.39 (95%CI −0.76 to −0.03). Comparison with local reference ranges, represented as percentage of predicted value, revealed similar impairments: FEV1 86.9 (95%CI 81.1 to 92.7), FVC 89.0 (95%CI 83.5 to 94.4), FEV1/FVC ratio 97.7 (95%CI 95.4 to 99.9). The prevalence of wheeze was 16.7%. CONCLUSION: We present spirometric abnormalities suggestive of restrictive lung disease with no evidence of obstructive defects or increased prevalence of wheeze