title: Long-term effects of intermittent oral alphacalcidol, calcium carbonate and low-calcium dialysis (1.25 mmol L-1) on secondary hyperparathyroidism in patients on continuous ambulatory peritoneal dialysis.
abstract: OBJECTIVE
  (i) To examine the effect of alphacalcidol [1 alpha(OH)D3] given as an oral dose twice weekly in combination with CaCO3 and low-calcium dialysis (1.25 mmol L-1) on the secondary hyperparathyroidism in continuous ambulatory peritoneal dialysis (CAPD). (ii) To examine the changes in peritoneal mass transfer for calcium, phosphorus, magnesium, lactate, creatinine, urea, glucose, pH and albumin after shift to low-calcium dialysis solution.
  
  
  METHODS
  An open study in patients on CAPD.
  
  
  METHODS
  Renal division, Rigshospitalet, Copenhagen.
  
  
  METHODS
  Thirty-nine patients were included and completed 12 weeks of treatment. Thirty of the patients completed 52 weeks of treatment. A peritoneal equilibrium test (PET) was performed in seven patients.
  
  
  METHODS
  Following two sets of blood samples obtained as basal values the calcium concentration was reduced in the dialysis fluid from 1.75 mmol L-1 to 1.25 mmol L-1. Increasing doses of oral 1 alpha(OH)D3 were then administered under careful control of p-ionized calcium (p-Ca2+) and p-inorganic phosphate (p-P1). Blood samples were obtained every 2-4 weeks for 52 weeks. PET was performed using standard dialysis fluid and 1 week later using low-calcium dialysis fluid after a preceding overnight dwell. Two litres of glucose 22.7 mg mL-1 were used.
  
  
  METHODS
  Intact parathyroid hormone (PTH), p-Ca2+, p-P1, doses of CaCO3, doses of 1 alpha(OH)D3, peritoneal mass transfer for calcium, inorganic phosphate, magnesium, lactate, creatinine, urea, glucose and albumin.
  
  
  RESULTS
  Thirty nine patients with initial PTH values 144 +/- 26 pg mL-1 were followed for 12 weeks and 30 patients for 52 weeks. A negative calcium balance was induced after shifting to low-calcium dialysis fluid. After 2 weeks of treatment a significant increase of PTH by approximately 60% and a small but significant decrease of p-Ca2+ was observed. After 12 weeks of treatment with increasing doses of 1 alpha(OH)D3 and CaCO3, PTH was again reduced to levels not significantly different from the initial values. After 52 weeks of treatment no deterioration of the secondary hyperparathyroidism was seen.
  
  
  CONCLUSIONS
  A calcium concentration of 1.25 mmol L-1 in the CAPD dialysate made it possible to reduce the amount of aluminium-containing phosphate binder, to increase the doses of CaCO3 and to use pulse oral 1 alpha(OH)D3 without causing severe hyper-calcaemia in the patients. After a short elevation of PTH, the PTH levels remained at normal or near normal levels and the long-term results clearly demonstrated that an aggravation of the secondary hyperparathyroidism could be inhibited.
authors: Medical Department P, Rigshospitalet, University of Copenhagen, Denmark.
authors: L
authors: L
authors: Brandi
authors: P K
authors: PK
authors: Nielsen
authors: S
authors: S
authors: Bro
authors: H
authors: H
authors: Daugaard
authors: K
authors: K
authors: Olgaard
mesh_terms: D000418:Albumins / Q000378:metabolism; D002118:Calcium / Q000032:analysis* / Q000378:metabolism; D002119:Calcium Carbonate / Q000494:pharmacology*; D003404:Creatinine / Q000378:metabolism; D015314:Dialysis Solutions / Q000737:chemistry*; D005260:Female; D005947:Glucose / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006887:Hydroxycholecalciferols / Q000494:pharmacology*; D006934:Hypercalcemia / Q000209:etiology / Q000378:metabolism*; D006962:Hyperparathyroidism, Secondary / Q000209:etiology / Q000378:metabolism*; D019344:Lactic Acid / Q000378:metabolism; D008274:Magnesium / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D010531:Peritoneal Dialysis, Continuous Ambulatory / Q000009:adverse effects*; D010758:Phosphorus / Q000378:metabolism; D013997:Time Factors; D016896:Treatment Outcome; D014508:Urea / Q000378:metabolism
chemical_list: D000418:Albumins; D015314:Dialysis Solutions; D006887:Hydroxycholecalciferols; D010758:Phosphorus; D019344:Lactic Acid; D014508:Urea; D003404:Creatinine; D002119:Calcium Carbonate; D008274:Magnesium; D005947:Glucose; D002118:Calcium; C008088:alfacalcidol