Summary of findings 1. As-required FABA/ICS inhalers compared with as-required FABA inhalers for mild asthma
| As‐required FABA/ICS inhalers compared with as‐required FABA inhalers for mild asthma | ||||||
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Patient or population: Mild asthma Setting: Community Intervention: As‐required FABA/ICS inhalers Comparison: As‐required FABA inhalers | ||||||
| Outcomes | Anticipated absolute effects$ (95% CI) |
Relative effect
(95% CI) |
Number of participants
(studies) |
Certainty of the evidence
(GRADE) | Comments | |
| Risk with as-required FABA inhalers | Risk with as-required FABA/ICS inhalers | |||||
| Asthma exacerbation requiring systemic steroid follow‐up: 52 weeks | 109 per 1000 | 52 per 1000 (40 to 68) | OR 0.45, 95% CI 0.34 to 0.60 | 2997 (2 RCTs) | ⊕⊕⊕⊕ HIGH*† | People with mild asthma treated with combined inhalers have substantially fewer exacerbations requiring systemic steroid than those treated with FABA alone. |
| Hospital admission, ED and urgent care visits follow‐up: 52 weeks | 34 per 1000 | 12 per 1000 (7 to 21) | OR 0.35, 95% CI 0.20 to 0.60 | 2997 (2 RCTs) | ⊕⊕⊝⊝ LOW†‡ | People with mild asthma treated with combined inhalers probably have substantially fewer exacerbations requiring hospital admission, ED attendance or urgent care visit than those treated with FABA alone. |
| Asthma control follow‐up: 52 weeks Lower scores=better control | Mean baseline ACQ‐5 ranged from 1.1 to 1.61 | MD −0.15, 95% CI −0.20 to −0.10 | ‐ | 2859 (2 RCTs) | ⊕⊕⊕⊝ MODERATE† | MCID for ACQ‐5 is 0.5. A third study reported no difference in asthma symptom scores between the two arms. |
| Inhaled steroid dose assessed with: mean daily inhaled steroid dose, μg beclomethasone equivalent follow‐up: 52 weeks | The mean inhaled steroid dose was 18.7 µg beclomethasone | MD 76.50 µg beclomethasone higher (69.40 higher to 83.60 higher) | ‐ | 2554 (2 RCTs) | ⊕⊕⊕⊝ MODERATE† | People with mild asthma treated with a combined inhaler have a higher daily inhaled steroid dose than those treated with a FABA alone. |
| Total systemic steroid dose assessed with: mg prednisolone total over 52 weeks follow‐up: 52 weeks | The mean total systemic steroid dose was 17.4 mg prednisolone | MD 9.90 mg prednisolone lower (19.38 lower to 0.42 lower; participants=443) | ‐ | 443 (1 RCT) | ⊕⊕⊝⊝ LOW†§ | Total systemic steroid dose was similar and small in both: those given combined inhalers and those given FABA alone. |
| Adverse events follow‐up: 52 weeks | 486 per 1000 | 437 per 1000 (402 to 473) | OR 0.82 (0.71 to 0.95) | 3002 (2 RCTs) | ⊕⊕⊕⊝ MODERATE† | Slightly fewer adverse events occurred in those taking combination inhalers compared with those taking FABA alone. |
| $The risk in the intervention group (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). | ||||||
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GRADE Working Group grades of evidence
High certainty ⊕⊕⊕⊕: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty ⊕⊕⊕: we are moderately confident in the effect estimate; the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty ⊕⊕: our confidence in the effect estimate is limited; the true effect may be substantially different from the estimate of the effect. Very low certainty ⊕: we have very little confidence in the effect estimate; the true effect is likely to be substantially different from the estimate of effect. | ||||||
*Upgraded as large effect (OR <0.5) with fairly tight CIs.
†Downgraded as included open label study.
‡Downgraded as based on a small number of events.
§Downgraded as based on one study with a relatively small number of participants.
ACQ-5, Asthma Control Questionnaire‐5; ED, emergency department; FABA, fast‐acting β₂‐agonist; ICS, inhaled corticosteroid; MCID, minimum clinically important difference; MD, mean difference; RCT, randomised controlled trial.