Summary of findings 6. Hydroxyurea compared to RBC transfusion for prevention of SCI in people with SCD who had a stroke (secondary prevention).
| Hydroxyurea compared to RBC transfusion for prevention of SCI in people with SCD who had a stroke (secondary prevention) | ||||||
| Patient or population: prevention of SCI in people with SCD who had a stroke (secondary prevention) Setting: outpatients Intervention: hydroxyurea Comparison: RBC transfusion | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Risk with RBC transfusion | Risk with hydroxyurea | |||||
| Proportion of participants developing new or progressive SCI lesions | Moderate | Peto OR 7.28 (0.14 to 366.91) | 133 (1 RCT) | ⊕⊝⊝⊝ VERY LOW 1 2 3 | ||
| 72 per 1000 | 524 per 1000 (10 to 26,418) | |||||
| All‐cause mortality | Low** | OR 1.02 (0.06 to 16.41) | 133 (1 RCT) | ⊕⊝⊝⊝ VERY LOW 1 2 3 | ||
| 26 per 1000 | 208 per 1000 (4 to 10,507) |
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| High | ||||||
| 33 per 1000 | 264 per 1000 (5 to 13,336) |
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| SCD‐related SAEs ‐ ACS | Trial population | RR 0.33 (0.04 to 3.08) | 133 (1 RCT) | ⊕⊝⊝⊝ VERY LOW 1 2 3 | ||
| 45 per 1000 | 15 per 1000 (2 to 140) | |||||
| SCD‐related SAEs ‐ pain crisis | Trial population | RR 3.15 (1.23 to 8.11) | 133 (1 RCT) | ⊕⊕⊝⊝ LOW 1 2 | ||
| 76 per 1000 | 239 per 1000 (93 to 614) | |||||
| Clinical stroke | Moderate | RR 14.78 (0.86 to 253.66) | 133 (1 RCT) | ⊕⊝⊝⊝ VERY LOW 1 2 3 | ||
| 72 per 1000 | 1000 per 1000 (62 to 1000) | |||||
| Cognitive function ‐ not reported | ‐ | ‐ | ‐ | ‐ | ‐ | |
| Quality of life ‐ not reported | ‐ | ‐ | ‐ | ‐ | ‐ | |
| *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).
**Mortality risk for control estimates from: Leikin 1989 ACS: acute chest syndrome; CI: confidence interval; RCT: randomised controlled trial; RR: risk ratio; OR: odds ratio; SAEs: serious adverse events; SCI: silent cerebral infarcts | ||||||
| GRADE Working Group grades of evidence High‐quality: we are very confident that the true effect lies close to that of the estimate of the effect Moderate‐quality: 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‐quality: our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect Very low‐quality: we have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect | ||||||
1 We downgraded the quality of the evidence by 1 due to risk of bias. Trial was not blinded and was stopped early
2 We downgraded the quality of the evidence by 1 due to indirectness. Only children with HbSS and HbSβº thalassaemia were included. If this review was only considering the quality of evidence for children with HbSS the quality of evidence would not have been downgraded for indirectness.
3 We downgraded the quality of the evidence by 1 due to imprecision. The estimate has wide confidence intervals that include clinically relevant benefit or harm or both