Summary of findings 2. Creatine for treating metabolic myopathies.
| Creatine for treating metabolic myopathies | ||||||
| Patient or population: patients with metabolic myopathies Settings: outpatient treatment Intervention: creatine Comparison: placebo | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of Participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| placebo | creatine | |||||
| Maximum voluntary contraction in mitochondrial diseases % | The mean maximum voluntary contraction in mitochondrial diseases in the control groups was 693.43 N (foot plantar flexion)1 | The mean maximum voluntary contraction in mitochondrial diseases in the intervention groups was 3.65 lower (11.17 lower to 3.86 higher) | 38 (2 studies) | ⊕⊕⊕⊕ high | ||
| Maximum voluntary contraction in glycogen storage disease type V % | The mean maximum voluntary contraction in glycogen storage disease type v in the control groups was 942.71 N (foot plantar flexion) | The mean maximum voluntary contraction in glycogen storage disease type V in the intervention groups was 1.69 lower (6.48 lower to 3.09 higher) | 28 (1 study) | ⊕⊕⊕⊕ high | ||
| Impairment of activities of daily living (ADL) in glycogen storage disease type V Visual numeric scale. Scale from: 1 to 10. | The mean impairment of activities of daily living (ADL) in glycogen storage disease type v in the control groups was 2.82,3 | The mean impairment of activities of daily living (ADL) in glycogen storage disease type V in the intervention groups was 0.54 higher (0.14 to 0.93 higher)3 | 19 (1 study) | ⊕⊕⊕⊕ high | ||
| Adverse events in mitochondrial diseases | See comment | See comment | 38 (3 studies) | Two patients reported muscle cramps during creatine treatment. | ||
| Adverse events in glycogen storage disease type V | See comment | See comment | 28 (2 studies) | Significant increase in muscle pain episodes in one trial. | ||
| *The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (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 | ||||||
| GRADE Working Group grades of evidence High quality: Further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate. | ||||||
1 Data obtained from the study by Kornblum et al. (Kornblum 2005). 2 Additional data from the study by Vorgerd et al. (Vorgerd 2002). 3 Higher values indicate more impairment.