Available evidence from this systematic review suggests that high dose vitamin D may prevent  asthma exacerbation .
CONTEXT Observational studies have suggested a relationship between vitamin D status and asthma-related respiratory outcomes .
The benefit of vitamin D supplementation for pulmonary function , symptoms and exacerbations is not well established .
OBJECTIVE To systematic ally review paediatric clinical trials investigating the role of vitamin D on asthma-related respiratory outcomes .
Budesonide/formoterol maintenance plus reliever therapy: a new strategy in pediatric asthma.
OBJECTIVES A fixed combination of long-acting beta(2)-agonists ( LABA ) plus inhaled corticosteroids ( ICS ) has never been proven to reduce asthma exacerbations vs ICS alone in children . This 12-month , double-blind , r and omized study in 341 children ( age range , 4 to 11 years ) with asthma uncontrolled on ICS investigated whether a novel regimen using budesonide/formoterol for maintenance and reliever therapy ( Symbicort maintenance and relief therapy [ SMART ] ) [ Symbicort ; AstraZeneca R&D , Lund , Sweden ] could reduce exacerbations . METHODS Patients received SMART ( budesonide/formoterol 80/4.5 microg qd maintenance plus additional inhalations for symptom relief ) , budesonide/formoterol 80/4.5 microg qd for maintenance ( fixed combination ) , or higher-dose budesonide 320 microg qd ( fixed-dose budesonide ) . Blinded as-needed medication ( terbutaline 0.4 microg ) was provided in both fixed-dose groups . RESULTS SMART prolonged the time to first exacerbation vs fixed-dose budesonide ( p = 0.02 ) and fixed-dose combination ( p < 0.001 ) . Rates of exacerbation requiring medical intervention were reduced by 70 to 79 % with SMART vs fixed-dose budesonide and fixed-dose combination ( 0.08/patient vs 0.28/patient and 0.40/patient , respectively ; both p < 0.001 ) . Mild exacerbation days and awakenings were significantly lower with SMART ; yearly growth improved by 1.0 cm vs fixed-dose budesonide ( p < 0.01 ) . CONCLUSION The SMART regimen using budesonide/formoterol for both maintenance and as-needed symptom relief reduces the exacerbation rate compared with both fixed-dose combination and higher fixed-dose ICS alone in children with asthma
Available evidence from this systematic review suggests that high dose vitamin D may prevent  asthma exacerbation .
CONTEXT Observational studies have suggested a relationship between vitamin D status and asthma-related respiratory outcomes .
The benefit of vitamin D supplementation for pulmonary function , symptoms and exacerbations is not well established .
OBJECTIVE To systematic ally review paediatric clinical trials investigating the role of vitamin D on asthma-related respiratory outcomes .