Summary of findings 1. Vitamin D compared with placebo or no intervention for chronic liver diseases in adults.
| Vitamin D compared with placebo or no intervention for chronic liver diseases in adults | ||||||
| Patient or population: people with chronic liver diseases Setting: in‐ and outpatients Intervention: vitamin D Comparison: placebo or no intervention | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (trials) | Certainty of the evidence (GRADE) | Comments | |
| Risk with placebo or no intervention | Risk with vitamin D | |||||
| All‐cause mortality Follow‐up: mean 7 months (1 to 18 months) |
Study population | RR 0.86 (0.51 to 1.45) | 1979 (27 RCTs) | ⊕⊝⊝⊝ very low 1 | ||
| 21 per 1000 | 18 per 1000 (11 to 30) | |||||
| Liver‐related mortality Follow‐up: 12 months |
Study population | RR 1.62 (0.08 to 34.66) | 18 (1 RCT) | ⊕⊝⊝⊝ very low 2 | No information was available to calculate absolute effects. | |
| ‐ | ‐ | |||||
| Serious adverse events Follow‐up: mean 10.5 months (6 to 12 months) |
Study population | ‐ | ‐ | ⊕⊝⊝⊝ very low 3 | ||
| Several serious adverse events were reported: hypercalcaemia (RR 5.00, 95% CI 0.25 to 100.8; 1 trial; 76 participants); myocardial infarction (RR 0.75, 95% CI 0.08 to 6.81; 2 trials; 86 participants); thyroiditis (RR 0.33, 95% CI 0.01 to 7.91; 1 trial; 68 participants); circular haemorrhoidal prolapse (RR 3.00, 95% CI 0.14 to 65.9; 1 trial; 20 participants); bronchopneumonia (RR 0.33, 95% CI 0.02 to 7.32; 1 trial; 20 participants). | ||||||
| Liver‐related morbidity | Study population | ‐ | (0 RCTs) | ‐ | ||
| ‐ | ‐ | |||||
| Health‐related quality of life | Study population | ‐ | (0 RCTs) | ‐ | ||
| ‐ | ‐ | |||||
| Non‐serious adverse events Follow‐up: mean 7 months (3 to 12 months) |
Study population | ‐ | ‐ | ⊕⊝⊝⊝ very low 3 | ||
| 1 trial reported 1 single non‐serious adverse event, and another trial reported 16 single non‐serious adverse events, for a total of 17 types of non‐serious adverse events. | ||||||
| Failure of sustained virological response Follow‐up: mean 16 months (6 to 18 months) |
Study population | RR 0.65 (0.42 to 1.01) | 630 (7 RCTs) | ⊕⊝⊝⊝ very low4 | ||
| 484 per 1000 | 315 per 1000 (203 to 489) | |||||
| *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; RCT: randomised clinical trial; RR: risk ratio | ||||||
| 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. | ||||||
1Downgraded because of risk of bias (1 level) (all trials were at high risk of bias); and imprecision (2 levels) (few events, and the optimal information size of 63,116 participants (based on a proportion of 2% in the control group, a relative risk reduction of 20%, an alpha of 1.25%, and a beta of 10%) was not met; wide CI which included both benefits and harms). 2Downgraded because of risk of bias (1 level) (the trial was at high risk of bias); and imprecision (2 levels) (very few events, and wide CI which included both benefits and harms). 3Downgraded because of risk of bias (1 level) (all trials were at high risk of bias); and imprecision (2 levels) (very few events, and wide CI which included both benefits and harms). 4Downgraded because of risk of bias (1 level) (all trials were at high risk of bias); imprecision (2 levels) (the optimal information size of 7570 participants (based on a proportion of 48% in the control group, a relative risk reduction of 20%, an alpha of 1.25%, and a beta of 10%) was not met); inconsistency (1 level) (considerable heterogeneity); and indirectness (3 levels)(sustained virological response is a surrogate outcome).