Summary of findings 1. Carnitine supplements versus control (placebo or standard care) for people with chronic kidney disease requiring dialysis.
| Carnitine supplements versus control (placebo or standard care) for people with CKD requiring dialysis | ||||||
| Patient or population: people with CKD requiring dialysis Setting: haemodialysis and peritoneal dialysis Intervention: carnitine supplements Comparison: placebo or standard care | ||||||
| Outcomes | Anticipated absolute effects (95% CI) | Relative effect (95% CI) | No. of participants (RCTs) | Certainty | ||
| Risk with control | Risk with L‐carnitine | |||||
| Quality of life |
SF‐36 PCS Follow‐up: range 2 to 12 months |
The PCS SMD was 0.57 higher in the L‐carnitine group (0.15 lower to 1.28 higher) compared to the control group | ‐ | 134 (4) | ⨁⨁OO Low1,2,3 | |
|
SF‐36 MCS Follow‐up: range 2 to 12 months |
The MCS SMD was 0.70 higher in the L‐carnitine group (0.22 higher to 1.18 higher) compared to the control group | ‐ | 134 (4) | ⨁⨁OO Low1,3 | ||
|
Total scores Follow‐up: range 4 to 6 months |
The total QoL compared score SMD was 0.02 lower in the L‐carnitine group (0.29 lower to 0.25 higher) compared to the control group | ‐ | 230 (3) | ⨁⨁OO Low1,3 | ||
|
Fatigue score Follow‐up: range 3 to 6 months |
The fatigue score SMD was 0.01 higher in the L‐carnitine group (0.20 lower to 0.23 higher) compared to the control group | ‐ | 353 (2) | ⨁⨁OO Low3,4 | ||
|
Adverse events Follow‐up: range 3 to 12 months |
113 per 1,000 | 129 per 1,000 (97 to 170) | RR 1.14 (0.86 to 1.51) | 1041 (12) | ⨁⨁OO Low3,5 | |
|
Muscle cramps Follow‐up: range 2 to 6 months |
315 per 1,000 | 139 per 1,000 (57 to 343) | RR 0.44 (0.18 to 1.09) | 102 (2) | ⨁⨁OO Low1,3 | |
| Anaemia‐related markers |
Hb Follow‐up: range 0.5 to 12 months |
The mean Hb was 0.46 g/dL higher in the L‐carnitine group (0.18 g/dL higher to 0.74 g/dL higher) compared to the control group | ‐ | 1795 (26) | ⨁⨁OO Low2,6 | |
|
HCT Follow‐up: range 3 to 18 months |
The mean HCT was 1.78% higher in the L‐carnitine group (0.38% higher to 3.18% higher) compared to the control group | ‐ | 950 (14) | ⨁⨁OO Low1,2 | ||
|
Intradialytic hypotension Follow‐up: range 2 to 4 months |
179 per 1,000 | 136 per 1,000 (61 to 303) | RR 0.76 (0.34 to 1.69) | 128 (3) | ⨁⨁OO Low1,3 | |
| *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). CI: confidence interval; CKD: chronic kidney disease; Hb: haemoglobin; HCT: haematocrit; MCS: mental component scale; MD: mean difference; PCS: physical component scale; RCT: randomised controlled trial; RR: risk ratio; SMD: standardised mean difference; VAS: visual analogue scale | ||||||
| GRADE Working Group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect Moderate certainty: 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 certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect | ||||||
1. Down‐graded one level due to a serious risk of bias: all studies had a high overall risk of bias
2. Down‐graded one level due to inconsistency: there was considerable heterogeneity
3. Down‐graded because the number of the included participants did not meet the optimal information size of 400
4. Down‐graded one level due to a serious risk of bias: 1 of the 2 studies had a high overall risk of bias
5. Down‐graded one level due to a serious risk of bias: 8 of the 11 studies had a high overall risk of bias
6. Down‐graded one level due to a serious risk of bias: 21 of the 23 studies had a high overall risk of bias