Effect of metabolic acidosis on hyperlipidemia in uremia.

Nine patients (aged 18+/-1 years) on maintenance hemodialysis with metabolic acidosis and hyperlipidemia were studied before and after 2 weeks of oral sodium bicarbonate (NaHCO(3)) treatment to correct the acidosis. To control for the effect of additional sodium, they were also studied after 2 weeks of an equivalent amount of oral sodium chloride (NaCl). Oral NaHCO(3 )treatment led to significant increases in venous pH, serum bicarbonate, and serum 1, 25-dihydroxyvitamin D(3) concentrations, but no significant change in total and ionized calcium, phosphate, sodium, potassium, creatinine, blood urea nitrogen, and intact parathyroid hormone concentrations. Oral NaCl did not change any of the biochemical parameters. Before treatment of acidosis, these uremic patients had high serum triglycerides, low serum high-density lipoprotein (HDL) cholesterol, but normal total cholesterol compared with controls. Following 2 weeks of NaHCO(3) treatment, there was a significant decrease in the serum concentrations of triglycerides (P<0.01). HDL and total cholesterol did not change. There were no changes in triglycerides, HDL or total cholesterol from baseline values following 2 weeks of NaCl. Thus treatment of metabolic acidosis ameliorated hypertriglyceridemia but had no effect on HDL and total cholesterol in patients with uremia on hemodialysis. The underlying mechanism may involve 1,25-dihydroxyvitamin D3.