Across eight randomised trials (1,204 participants with chronic kidney disease stages 3a-5), dietitian-delivered nutrition education reduced systolic blood pressure by 6.23 mmHg and diastolic by 4.01 mmHg versus usual care, rated high-certainty evidence from four trials (n = 398). Estimated glomerular filtration rate and body mass index showed little to no change. Quality of life appeared to improve substantially, but the confidence interval crossed zero (SMD 0.99, 95% CI -0.31 to 2.29) on low-certainty evidence. Individual and group formats performed similarly in exploratory analyses.
The blood pressure result is the clinically meaningful signal. A 6 mmHg systolic reduction is comparable to what a modest antihypertensive dose achieves, and in CKD, where hypertension both drives and results from kidney damage, that matters for cardiovascular risk, which outpaces kidney failure as a cause of death in earlier stages. The null eGFR finding deserves caution rather than dismissal: trials were short, and eGFR changes slowly, so these studies were likely underpowered to detect kidney-function effects. The quality-of-life estimate is too imprecise to act on, since the interval spans both harm and large benefit. Pooling heterogeneous interventions (sodium, protein, potassium advice) also blurs which components do the work. Practically, the group-versus-individual parity is useful: group sessions could extend dietitian reach at lower cost. Adults with CKD should ask about referral to a renal dietitian as an adjunct to, not replacement for, blood pressure medication. Confirmatory rather than paradigm-shifting, but it firmly supports a low-cost intervention.