Cochrane · systematic review · CD013590
Antioxidant supplementation for sickle cell disease
Bolarinwa, AB, Oduwole, O, Okebe, J, et al. · Cochrane Database of Systematic Reviews · 2024 · Cochrane Library
Cystic Fibrosis and Genetic DisordersAMSTAR 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
35
current version
GRADE rated
21
No studies
13
Included studies
NR
No studies 13 · 37.1%Ungraded 1 · 2.9%Very low 11 · 31.4%Low 10 · 28.6%Moderate 0 · 0%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
Vitamin C 1400 mg plus vitamin E 800 mg versus placebo for sickle cell disease at up to six months
Population: adults with sickle cell disease (adults with homozygous SCA or sickle beta 0 thalassaemia SCD)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Frequency of pain crisis Vitamin C 1400 mg plus vitamin E 800 mg vs placebo | RR 1.18 [0.64, 2.18] | 1 study · 83 participants | Very low Downgraded: risk of bias, imprecision |
Severity of pain (use of opioid analgesics) Vitamin C 1400 mg plus vitamin E 800 mg vs placebo | RR 1.33 [0.4, 4.37] | 1 study · 83 participants | Very low Downgraded: risk of bias, imprecision |
QoL of participants living with SCD and their caregivers Vitamin C 1400 mg plus vitamin E 800 mg vs placebo | no estimate extracted | NR | No studies |
Adverse effects Vitamin C 1400 mg plus vitamin E 800 mg vs placebo | RR 0.56 [0.31, 1] | 1 study · 83 participants | Very low Downgraded: risk of bias, imprecision |
Frequency of hospitalization Vitamin C 1400 mg plus vitamin E 800 mg vs placebo | no estimate extracted | NR | No studies |
Frequency of sickle cell‐related complications: acute chest syndrome Vitamin C 1400 mg plus vitamin E 800 mg vs placebo | RR 2.66 | 1 study · 83 participants | Very low Downgraded: risk of bias, imprecision |
Haemoglobin status (g/L) Vitamin C 1400 mg plus vitamin E 800 mg vs placebo | no estimate extracted | 1 study · 83 participants | Very low Downgraded: risk of bias, imprecision |
Zinc versus placebo for sickle cell disease at up to six months
Population: children and adults with sickle cell disease
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Frequency of crisis Zinc vs placebo | Rate ratio 0.62 [0.17, 2.29] | 1 study · 36 participants | Low Downgraded: risk of bias, imprecision |
Severity of pain Zinc vs placebo | no estimate extracted | NR | No studies |
QoL of participants living with SCD and their caregivers Zinc vs placebo | no estimate extracted | NR | No studies |
Adverse effects Zinc vs placebo | no estimate extracted | NR | No studies |
Frequency of hospitalization Zinc vs placebo | no estimate extracted | NR | No studies |
Frequency of sickle cell‐related complications: number of participants with completely healed leg ulcer ( Zinc vs placebo | RR 2 [0.6, 6.72] | 1 study · 34 participants | Very low Downgraded: risk of bias, imprecision |
Haemoglobin status (g/dL) Zinc vs placebo | MD 1.26 [0.44, 1.26] | 1 study · 36 participants | Low Downgraded: risk of bias, imprecision |
N‐acetylcysteine (1200 mg) versus placebo for sickle cell disease at up to six months
Population: sickle cell disease
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Frequency of crisis (number of pain days) N‐acetylcysteine (1200 mg) vs placebo | Rate ratio 0.99 [0.53, 1.84] | 1 study · 96 participants | Low Downgraded: risk of bias, imprecision |
Severity of pain (maximum pain intensity on pain days) N‐acetylcysteine (1200 mg) vs placebo | MD 0.17 | 1 study · 96 participants | Low Downgraded: risk of bias, imprecision |
QoL of participants living with SCD and their caregivers (measured using SF‐36 scale) N‐acetylcysteine (1200 mg) vs placebo | no estimate extracted | 1 study · 96 participants | Very low Downgraded: risk of bias, imprecision |
Adverse effects N‐acetylcysteine (1200 mg) vs placebo | RR 0.92 [0.75, 1.14] | 1 study · 96 participants | Low Downgraded: risk of bias, imprecision |
Frequency of hospitalization N‐acetylcysteine (1200 mg) vs placebo | rate ratio 0.98 | 1 study · 96 participants | Low Downgraded: risk of bias, imprecision |
Frequency of sickle cell‐related complications (acute chest syndrome) N‐acetylcysteine (1200 mg) vs placebo | RR 5 [0.25, 101.48] | 1 study · 96 participants | Very low Downgraded: risk of bias, imprecision |
Haemoglobin status N‐acetylcysteine (1200 mg) vs placebo | no estimate extracted | 1 study · 96 participants | Low Downgraded: risk of bias, imprecision |
L‐arginine versus placebo for sickle cell disease at up to six months
Population: sickle cell disease
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Frequency of crisis (monthly crisis) L‐arginine vs placebo | RR 0.71 [0.26, 1.95] | 1 study · 50 participants | Low Downgraded: risk of bias, imprecision |
Severity of pain (assessed using a 10‐cm visual analogue scale from 0 to 10; lower score is better) L‐arginine vs placebo | no estimate extracted | 2 studies · 125 participants | Low Downgraded: risk of bias |
QoL of participants living with SCD and their caregivers L‐arginine vs placebo | no estimate extracted | NR | No studies |
Adverse effects L‐arginine vs placebo | no estimate extracted | 2 studies · 125 participants | Ungraded |
Frequency of hospitalization (number of days in hospital) L‐arginine vs placebo | no estimate extracted | 2 studies · 125 participants | Very low Downgraded: risk of bias, imprecision |
Frequency of sickle cell‐related complications L‐arginine vs placebo | no estimate extracted | NR | No studies |
Haemoglobin status (g/dL) L‐arginine vs placebo | MD 0.4 | 2 studies · 106 participants | Low Downgraded: risk of bias, imprecision |
Omega‐3 versus placebo for sickle cell disease at up to six months
Population: sickle cell disease
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Frequency of crisis Omega‐3 vs placebo | no estimate extracted | NR | No studies |
Severity of pain Omega‐3 vs placebo | no estimate extracted | NR | No studies |
QoL of participants living with SCD and their caregivers Omega‐3 vs placebo | no estimate extracted | NR | No studies |
Adverse effects (any adverse effect) Omega‐3 vs placebo | RR 1.05 [0.74, 1.48] | 1 study · 67 participants | Very low Downgraded: risk of bias, imprecision |
Frequency of hospitalization Omega‐3 vs placebo | no estimate extracted | NR | No studies |
Frequency of sickle cell‐related complications Omega‐3 vs placebo | no estimate extracted | NR | No studies |
Haemoglobin status Omega‐3 vs placebo | MD 0.36 | 1 study · 67 participants | Very low Downgraded: risk of bias, imprecision |