Table 2.

Comparison of bronchodilator response and asthma prevalence in children with sickle cell disease and asthma.

Study (year)	Study design/description	Asthma (%)	Positive BD response (%)	Comment	Ref.
Leong et al. (1997)	Prospective study comparing BD response in 40 consecutive children with SCD-(SS, SC, Sβ+ thal) age range 6–19 years with ten healthy controls of siblings of study patients without history of reactive airway disease	40	12.5	No BD response in controls	[44]
Koumbourlis et al. (2001)	Retrospective evaluation of lung function in 63 children aged 5–18 years with SCD-SS to determine association between ACS, sickle cell pain and BD response	22	54	No association between BD response and VOC, ACS or abnormal lung function	[80]
Sylvester et al. (2006)	Prospective study of 40 children with SCD-SS, with and without ACS comparing BD response between the two groups	20	12.5	No difference in BD response between ACS and non-ACS	[79]
Ozbek et al. (2007)	Prospective study comparing BD response in 31 children aged 6–16 years with SCD (SS, SC, Sβ+ thal) and in steady state to 30 healthy controls	6.5	9.7	No BD response in controls	[42]
Field et al. (2010)	Prospective study of 99 children with SCD without regard to past SCD morbidity or physician diagnosis of asthma examining the relationship between BD response and methacholine)	22	15	No association between BD response and methacholine challenge	[43]

ACS: Acute chest syndrome; BD: Bronchodilator; SCD: Sickle cell disease; Sβ+ thal: Sickle cell with β+ thalassemia; SCD-SS: Hemoglobin SS sickle cell disease; VOC: Vaso-occlusive crisis.