USA: Monthly diet therapy focused on lowering serum phosphate levels may be safe and effective for the treatment of persistent hyperphosphatemia in patients on hemodialysis, according to a recent review in the Clinical Journal of the American Society of Nephrology. Hyperphosphatemia is an electrolyte disorder characterized by increased blood level of phosphate.
In patients undergoing maintenance hemodialysis, hyperphosphatemia is a persistent problem that contributes to bone and vascular complications. Dietitians work with patients in some dialysis centers to help them manage serum phosphate. Given the regularity of hyperphosphatemia in this population and constraints on kidney dietitian time, David E. St-Jules, Department of Nutrition, University of Nevada, Reno, Nevada, and colleagues aimed to evaluate the evidence for this practice.
For the purpose, the researchers performed a systematic review and meta-analysis of clinical trials. The online databases were searched for RCTs that examined theeffect of phosphate-specific diet therapy provided by a dietitian on serum phosphate in individuals on hemodialysis..
Of the 8054 titles/abstracts that were identified 168 articles were reviewed, and 12 clinical trials (11 randomized, one nonrandomized) were included.
Key findings of the study include:
Diet therapy reduced serum phosphate compared with controls in all studies, reaching statistical significance in eight studies, although overall certainty of evidence was low, primarily due to randomization issues and deviations from protocol.
Monthly diet therapy (20–30 minutes) significantly lowered serum phosphate in patients with persistent hyperphosphatemia for 4–6 months, without compromising nutrition status (mean difference, −0.87 mg/dl), but appeared unlikely to maintain these effects if discontinued.
The trials were too varied in design, setting, and approach to appropriately pool in meta-analysis, and were too limited in number to evaluate the timing, dose, and strategy of phosphate-specific diet therapy.
"There is low-quality evidence that monthly diet therapy by a dietitian appears to be a safe and efficacious treatment for persistent hyperphosphatemia in patients on HD," wrote the authors.
"Effect of Phosphate-Specific Diet Therapy on Phosphate Levels in Adults Undergoing Maintenance Hemodialysis: A Systematic Review and Meta-Analysis," is published in the Clinical Journal of the American Society of Nephrology.
DOI: https://cjasn.asnjournals.org/content/16/1/107