Tighter restriction of protein intake does not increase the likelihood of survival among CKD patients not yet on dialysis, according to an Italian study that also showed that serum phosphate levels predict progression to dialysis and death.
Andrea Pota, MD, PhD, of the University of Naples, and his colleagues compared the effect of two different low-protein diets—0.55 and 0.8 g/kg/day—on survival in 423 patients with stage 4 or 5 CKD. A total of 212 and 211 patients were assigned to the 0.55 and 0.8 g/kg/day diet, respectively. During follow up, which ranged from six to 48 months, 48 patients died and 83 required dialysis. Dr. Pota’s team observed no significant difference in death risk between the two groups.
In addition, each 1 mg/dL increment in serum phosphate level was associated with a 39% increased risk of death and a 36% increased risk of progressing to dialysis, the researchers found.
The use of ACE inhibitors and angiotensin receptor blockers was associated with a 44% decreased risk of death and need for dialysis.
“Therefore, these drugs are the first choice treatment for hypertension in CKD,” the researchers noted.
The study is the first to compare the effect of two low-protein diets on survival, Dr. Pota said.