Summary of findings 4. Transfusions continued compared to transfusions halted for prevention of SCI in people with SCD and normalised TCD velocities.
| Transfusions continued compared to transfusions halted for prevention of SCI in people with SCD and normalised TCD velocities | ||||||
| Patient or population: prevention of SCI in people with SCD and normalised TCD velocities Setting: outpatients Intervention: transfusions continued Comparison: transfusions halted | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Risk with transfusions halted | Risk with transfusions continued | |||||
| Proportion of participants developing new or progressive SCI lesions | Trial population | RR 0.29 (0.09 to 0.97) | 77 (1 RCT) | ⊕⊕⊝⊝ LOW 1 2 | One patient in each group had no follow‐up MRI | |
| 275 per 1000 | 80 per 1000 (25 to 267) | |||||
| All‐cause mortality | Low** | Peto OR 8.00 (0.16 to 404.12) | 79 (1 RCT) | ⊕⊝⊝⊝ VERY LOW 1 2 3 | ||
| 26 per 1000 | 208 per 1000 (4 to 10,507) |
|||||
| High | ||||||
| 33 per 1000 | 264 per 1000 (5 to 13,336) |
|||||
| Clinical stroke | Trial population | RR 0.22 (0.01 to 4.35) | 79 (1 RCT) | ⊕⊝⊝⊝ VERY LOW 1 2 3 | ||
| 49 per 1000 | 11 per 1000 (0 to 212) | |||||
| SCD‐related SAEs ‐ ACS | See comment | ‐ | 79 (1 RCT) | ⊕⊝⊝⊝ VERY LOW 1 2 4 | No comparative numbers reported | |
| SCD‐related SAEs ‐ pain crisis | See comment | ‐ | 79 (1 RCT) | ⊕⊝⊝⊝ VERY LOW 1 2 4 | No comparative numbers reported | |
| 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; SAEs: serious adverse events; SCD: sickle cell disease; SCI: silent cerebral infarcts; TCD: transcranial doppler | ||||||
| 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 evidence by 1 due to risk of bias. There was no description of allocation concealment, there was a risk of performance bias, and the trial was stopped early
2 We downgraded the quality of evidence by 1 due to indirectness. Only children with HbSS or HbSβº thalassaemia included in the trial. 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 evidence by 1 due to imprecision. The estimate has wide CIs that include clinically relevant benefit and harm
4 We downgraded the quality of evidence by 1 due to imprecision. No comparative numbers were provided