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. 2017 Dec 11;9(12):1345. doi: 10.3390/nu9121345

Table 3.

Grading of Recommendations, Assessment, Development and Evaluation (GRADE) assessment of polyphenol supplementation compared to placebo for improving cardiovascular risk factors in haemodialysis patients.

Quality Assessment Number of Patients Effect Quality
Number of Studies Study Design Risk of Bias Inconsistency Indirectness Imprecision Other Considerations Polyphenol Placebo Absolute (95% CI)
Oxidative stress (myeloperoxidase)
2 Randomised trials Not serious Not serious Not serious Serious a Strong effect 82 44 MD 90.1 SD lower (135.8 lower to 44.4 lower) MODERATE
Oxidative stress (other markers—not pooled)
5 Randomised trials Not serious serious b Not serious Serious c None - - See comment MODERATE
Inflammation (CRP)
5 Randomised trials Not serious very serious d Not serious Serious e None 96 99 MD 1.9 mg/dL higher (2.2 lower to 6.1 higher) VERY LOW
Inflammation (IL-6)
2 Randomised trials Not serious very serious d Not serious Serious e Both pomegranate studies 79 49 MD 1.6 mg/dL lower (5.1 lower to 1.96 higher) VERY LOW
Inflammation (AOPP)
3 Randomised trials Not serious very serious d Not serious Serious e All pomegranate studies 96 57 MD 17.7 mg/dL lower (46.5 lower to 11.1 higher) VERY LOW
Diastolic blood pressure
4 Randomised trials Not serious Not serious Not serious Not serious None 133 112 MD 5.6 mmHg lower (8.47 lower to 2.78 lower) HIGH
Systolic blood pressure
4 Randomised trials Not serious Serious f Not serious Serious e None 107 86 MD 10 mmHg lower (21.4 lower to 1.4 higher) LOW
Hemodynamic measures (other markers—not pooled)
4 Randomised trials Not serious Serious g Not serious Serious h None - - Not pooled. See Table 2 LOW
Lipid profile (TG)
4 Randomised trials Not serious Serious f Not serious Very serious e None 110 81 MD 26.5 mg/dL lower (47.2 lower to 5.8 lower) VERY LOW
Lipid profile (Total-C)
4 Randomised trials Not serious Very serious d Not serious Very serious e None 110 81 MD 11.2 mg/dL lower (24.8 lower to 2.3 higher) VERY LOW
Lipid profile (HDL-C)
4 Randomised trials Not serious Not serious Not serious Serious e None 110 81 MD 2.4 mg/dL higher (0.1 lower to 4.8 higher) MODERATE
Lipid profile (LDL-C)
4 Randomised trials Not serious Not serious Not serious Serious e None 110 81 MD 3.3 mg/dL lower (14.5 lower to 7.8 higher) MODERATE

CI: Confidence interval; dL: decilitre; HDL-C, High Density Lipoprotein Cholesterol; LDL-C, Low Density Lipoprotein Cholesterol; MD: Mean difference; Total-C, Total Cholesterol; TG, Triglycerides. a Two studies were pooled in a meta-analysis for the outcome of myeloperoxidase. The 95%CI for the outcome was substantial (−135 to −44). b Although most measures of oxidative stress showed improvement from baseline in the intervention group; a number of control groups also showed improvement in this outcome. Therefore, decreasing confidence in the consistency of results for this outcome. c Although some had narrow measures of variance, other did show substantial imprecision in their measures of variance. d Heterogeneity was high (>70%). e The 95%CI was substantial. f Heterogeneity was substantial (50–70%). g Studies showed some improvement in mean arterial pressure and flow-mediated dilation; but other studies found no improvement. No improvement was seen in other measures. h Although individual studies and outcomes did not show significant variance; there is overall a small number of participants for each outcome as well as combined. This decreases confidence in the precision of the effects.