100 children of either sex, 5 to 15 years of age, with acute mild exacerbation of asthma attending Pediatric OPD or the Pediatric Chest Clinic were screened for enrolment in the study between May 2009 and April 2010. 10 of them were not enrolled as they had taken salbutamol or LABA prior to the screening. Ninety children were enrolled in the study and randomized to 2 groups- 45 to budesonide/salbutamol group (children received salbutamol and budesonide), and 45 to budesonide/formoterol group (children received formoterolbudesonide combination and placebo). Two patients in salbutamol group could not complete the study (one child could not perform spirometry and data were incomplete in the other patient). Trial profile is shown in Figure . No child failed to stabilize during the observation period.
Trial profile. ITT: Intention to treat.
The mean (SD) age of children in the budesonide/salbutamol group was 8.6 (2.3) years and 8.9 (2.1) years in the budesonide/formoterol group. The mean (SD) weight and height of children in budesonide/salbutamol group were 23.3 (6.3) kg and 127.2 (14.2) cm, respectively whereas in budesonide/formoterol group it was 25 (8.2) kg and 129 (13.5) cm, respectively. Presenting complaints like cough, breathlessness, night symptoms, type of asthma, frequency of exacerbation per year and family history of allergy or asthma were comparable between both the groups. The most common presenting symptoms were breathlessness, cough, night symptoms and wheeze in both the groups (Table ).
Baseline characteristics of the study subjects
The type of asthma presenting with mild acute exacerbation in this study were predominantly intermittent or mild persistent type in both the groups (Table ). Only one case of severe persistent asthma was enrolled in budesonide/salbutamol group. Presence of family history of allergy or asthma was present in 22 (49%) children in budesonide/salbutamol group and 21 (47%) in the budesonide/formoterol group.
The mean (SD) baseline MPIS score were 7.3 (1.2) and 7.2 (1.0) in the budesonide/salbutamol and budesonide/formoterol groups, respectively. The mean baseline spirometric parameters were similar in both the groups- FEV1 (% predicted) in the budesonide/salbutamol group at baseline was 58.2 (18.1)% while that of budesonide/formoterol group was 55.9 (14.8)%.
On comparing the post intervention values of percent predicted FEV1 between both the groups at 1, 5, 15, 30 and 60 min, there was no statistically significant difference at any of the time points and the difference between both the groups were always less than 10 (p > 0.05) (Table , Figure ). The mean (SD) absolute change in FEV1 (% predicted) from baseline to 60 min was 12.2 (13.2) in the budesonide/salbutamol group while in the budesonide/Formoterol group, it was 8.3 (13.0) with a p value of 0.16.
FEV1 (percent predicted) in the two groups at different time points
% predicted FEV1 at different time points in the 2 groups.
Intragroup analysis showed significant improvement in FEV1 (% predicted) (p < 0.0001) at 1, 5, 15, 30, 60 min compared to baseline in both the groups. The percentage change in FEV1 from baseline at different time points were also similar (Table ). Peak expiratory flow rates (PEFR), percentage predicted PEFR (Table ) and forced expiratory flow-50 (FEF 50) and percentage predicted FEF50 of both the groups were similar at different time points during the study. Table shows the percent change in PEFR from baseline at different time points. There was no significant difference between salbutamol and formoterol groups in other spirometric parameters also.
Percentage change in FEV1 from baseline at different time points
PEFR (percent predicted) in the two groups at different time points
Percentage change in PEFR from baseline at different time points
The Modified Pulmonary Index Scores of both the groups were similar at 1, 5, 15, 30 and 60 min of the study (Table ).
Modified Pulmonary Index Score (MPIS) in the two groups at different time points
Only 3 of the total 90 children experienced tremors. Two of them belonged to salbutamol group while one was from formoterol group; this difference was not statistically significant. None of the children had vomiting or palpitations. No child deteriorated during the study period or required hospitalization.