Addition of long-acting beta-agonists to inhaled corticosteroids for chronic asthma in children

A total of 25 trials representing 31 control-intervention comparisons were included in the review randomising 5572 children. Most of the participants were inadequately controlled on current ICS dose. We assessed the addition of LABA to the same dose of ICS and to an increased dose of ICS:

(1) The addition of LABA to ICS was compared to same dose ICS, namely 400 mcg/day of beclomethasone or less in 16 of the 24 studies. The mean age of participants was 10 years and males accounted for 64% of the study populations. The mean FEV1 at baseline was 80% of predicted or above in 10 studies; FEV1 61% to 79% of predicted in eight studies; and unreported in the remaining study. Participants were inadequately controlled before randomisation in all but seven studies. Compared to ICS alone, the addition of LABA to ICS was not associated with a significant reduction in exacerbations requiring oral steroids (seven studies, RR 0.92 95% CI 0.60 to 1.40). Compared to ICS alone, there was a significantly greater improvement in FEV1 with the addition of LABA (nine studies; 0.08 Litres, 95% CI 0.06 to 0.11) but no statistically significant group differences in symptom-free days, hospital admission, quality of life, use of reliever medication, and adverse events. Withdrawals occurred significantly less frequently with the addition of LABA.

(2) A total of seven studies assessed the addition of LABA to ICS therapy compared with an increased dose of ICS randomising 1021 children. The mean age of participants was 8 years with 67% of males. The baseline mean FEV1 was 80% of predicted or above in 2 of the 3 studies reporting this characteristic. All trials enrolled participants who were inadequately controlled on a baseline dose equivalent to 400 mcg/day of beclomethasone or less. There was no group significant difference in the risk of an exacerbation requiring oral steroids with the combination of LABA and ICS compared to a double dose of ICS (two studies, RR 1.5 95% CI 0.65 to 3.48). The increased risk of hospital admission with combination therapy was also not statistically significant (RR 2.21 95% CI 0.74 to 6.64). Compared to double dose ICS, use of LABA was associated with a significantly greater improvement in morning PEF (four studies; MD 7.55 L/min 95% CI: 3.57 to 11.53) and evening PEF L/min (three studies, MD 5.5 L/min; 95% CI 1.21 to 9.79), but there were insufficient data to aggregate data on FEV1, symptoms, rescue reliever use, and quality of life. There was no statistically significant difference in the overall risk of all cause withdrawals (five studies; RR 0.71; 95% CI 0.42 to 1.20. There was no group difference in the risk of overall adverse effects detected. Short term growth was significantly greater in children treated with combination therapy compared to double dose ICS (two studies: MD 1.2 cm/year; 95% CI 0.72 to 1.7).