Cochrane · systematic review · CD010391
Vitamin C for asthma and exercise‐induced bronchoconstriction
Milan, SJ, Hart, A, Wilkinson, M · Cochrane Database of Systematic Reviews · 2013 · Cochrane Library
AirwaysAMSTAR 2: not assessed
SoF tableOnly the outcomes this review put in its Summary of Findings table are listed (the Cochrane Handbook caps them at about seven per comparison). Its other analyses are not shown here.
Questions
10
current version
GRADE rated
7
No studies
3
Included studies
NR
No studies 3 · 30%Ungraded 0 · 0%Very low 2 · 20%Low 3 · 30%Moderate 2 · 20%High 0 · 0%
Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.
Questions and results
Summary of findings: Vitamin C supplementation compared with placebo for asthma
Population: adults and children with asthma
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Health‐related quality of life (HRQL) Summary of findings: Vitamin C supplementation vs placebo | no estimate extracted | 1 study · 201 participants | Low Downgraded: risk of bias |
Asthma exacerbations Summary of findings: Vitamin C supplementation vs placebo | no estimate extracted | 1 study · 16 participants | Very low Downgraded: risk of bias, imprecision |
Lung function: FEV1 (ml) (change from 0 to 16 weeks) Summary of findings: Vitamin C supplementation vs placebo | no estimate extracted | 1 study · 201 participants | Moderate Downgraded: risk of bias |
Asthma symptoms (change from 0 to 16 weeks) Summary of findings: Vitamin C supplementation vs placebo | no estimate extracted | 1 study · 201 participants | Moderate Downgraded: risk of bias |
Adverse events Summary of findings: Vitamin C supplementation vs placebo | no estimate extracted | 1 study · 41 participants | Very low Downgraded: risk of bias, imprecision |
Summary of findings: Vitamin C supplementation compared with placebo for exercise ‐induced bronchoconstriction/asthma
Population: adults and children with exercise‐induced bronchoconstriction/asthma
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Health‐related quality of life (HRQL) Summary of findings: Vitamin C supplementation vs placebo | no estimate extracted | NR | No studies |
Asthma exacerbations Summary of findings: Vitamin C supplementation vs placebo | no estimate extracted | NR | No studies |
Lung function: FEV1 % drop Postexercise Summary of findings: Vitamin C supplementation vs placebo | no estimate extracted | 1 study · 8 participants | Low Downgraded: risk of bias |
Asthma symptoms Summary of findings: Vitamin C supplementation vs placebo | no estimate extracted | 1 study · 8 participants | Low Downgraded: risk of bias |
Adverse events Summary of findings: Vitamin C supplementation vs placebo | no estimate extracted | NR | No studies |