Impact of acidosis on nutritional status in chronic peritoneal dialysis patients

Malnutrition is a well-recognized risk factor for survival in chronic dialysis patients. Experimental evidence links acidosis to decreases in albumin synthesis and increased breakdown. We studied serum bicarbonate, albumin, and total protein concentrations in 79 peritoneal dialysis patients (mean age 53 +/- 14 years) during a 21-month observation period. No changes were observed in blood urea nitrogen (66 +/- 19 vs 61 +/- 18 mg/dL), serum creatinine (9.8 +/- 4.5 vs 10.7 +/- 4.5 mg/dL), serum bicarbonate (25 +/- 3 vs 25 +/- 3 mEq/L), anion gap (16 +/- 3 vs 17 +/- 3 mEq/L), and serum albumin (3.6 +/- 0.6 vs 3.6 +/- 0.6 g/dL) concentrations between the first and last trimester of follow-up. A poor correlation was also found between serum albumin concentration and anion gap (R = -0.373) and bicarbonate (R = -0.172) concentrations. Finally, when grouped by acid-base status, serum protein (6.5 +/- 0.7 vs 6.5 +/- 0.8 g/dL) and albumin (4.0 +/- 0.4 vs 3.9 +/- 0.4 g/dL), concentrations were similar in patients with serum bicarbonate levels < or > or = 22 mEq/L, respectively. In conclusion, a mild to moderate degree of acidosis is not associated with decreases in serum albumin concentrations in stable chronic peritoneal dialysis patients.