Dietary Interventions for Mineral and Bone Disorder in People with Chronic Kidney Disease

Summary

A Cochrane review [Abstract] 1 included 9 studies with a total of 634 subjects. Study duration ranged from 4 to 24 weeks. Only one study reported death; none of the included studies reported cardiovascular events or fractures. Calcium-enriched bread increased serum calcium (MD 0.16 mmol/L, 95% CI 0.51 to 0.31;1 trial, n=53, low-quality evidence), decreased serum phosphorus (MD -0.41 mmol/L, 95% CI -0.51 to -0.31; n=53, low-quality evidence) and decreased the calcium × phosphate product (MD -0.62 mmol²/L², 95% CI -0.77 to -0.47; n=53, low-quality evidence).

Very low protein intake was not superior to conventional low protein intake in terms of effect on serum phosphorus (MD -0.12 mmol/L, 95% CI -0.50 to 0.25; 2 studies, n=41), serum calcium (MD 0.00 mmol/L, 95% CI -0.17 to 0.17), or alkaline phosphatase (MD -22.00 U/L, 95% CI -78.25 to 34.25). PTH was significantly lower in the very low protein intake group (MD -69.64 pmol/L, 95% CI -139.83 to 0.54; 2 studies, n=41).

One study reported no significant difference in the number of deaths between low phosphorus intake and normal diet (RR 0.18, 95% CI 0.01 to 3.82; n=279). Low phosphorus intake decreased serum phosphorus (MD -0.18 mmol/L, 95% CI -0.29 to -0.07; 2 studies, 359 participants; I²=0%).One study reported post-haemodialysis supplements did not increase serum phosphorus compared to normal diet (MD 0.12 mmol/L, 95% CI -0.24 to 0.49; n=40).One study reported low phosphorus intake plus lanthanum carbonate significantly decreased fibroblast growth factor 23 (19 participants: MD -333.80 RU/mL, 95% CI -526.60 to -141.00), but did not decrease serum phosphorus (MD -0.10 mg/dL, 95% CI -0.38 to 0.58; n=19) or PTH (MD 31.60 pg/mL, 95% CI -29.82 to 93.02; n=19).