What do systematic reviews say?

Inhaled corticosteroids plus standard care vs placebo or usual care

Inhaled corticosteroids plus standard care probably leads to lower admission to hospital or death compared with standard care (with or without placebo) (moderate certainty).

• Inhaled corticosteroids for the treatment of COVID‐19 2022 · Cochrane Headline outcomes only
  RR 0.72 [0.51, 0.99]
  2 studies · 2025 participants
  Moderate

Intervention not reported

The intervention showed no clear difference in death Duration of trials: 8 to 24 weeks (low certainty).

• Addition of anti‐leukotriene agents to inhaled corticosteroids for adults and adolescents with persistent asthma 2017 · Cochrane Headline outcomes only
  RR 3.1 [0.13, 75.1]
  6 studies · 1100 participants
  Low

Intervention not reported

The intervention showed no clear difference in death Duration of trials: 6 to 16 weeks (low certainty).

• Addition of anti‐leukotriene agents to inhaled corticosteroids for adults and adolescents with persistent asthma 2017 · Cochrane Headline outcomes only
  RR 0.35 [0.01, 8.49]
  2 studies · 761 participants
  Low

Intervention not reported

• Addition of anti‐leukotriene agents to inhaled corticosteroids for adults and adolescents with persistent asthma 2017 · Cochrane Headline outcomes only
  no estimate extracted
  3 studies · 834 participants
  Low