1980 Volume 22 Issue 6 Pages 679-687
The effect of vitamin D2 (VD2) supplementation on hypocalcemia in 54 hypocalcemic patients (29 males and 25 females) on chronic hemodialysis were studied. Calcium lactate (3 g/day), or VD2 (10, 000 IU/day, 50, 000 IU/day, and 80, 000 IU/day) were administered for 4 months in order to cor-rect hypocalcemia observed in all patients before treatment. Serum calcium, phosphate and alkaline phosphatase levels were measured and the effects of VD2 supplementation of these parameters of calcium metabolism were also studied. 1) Calcium lactate, or 10, 000 IU/day of VD2 were not effec-tive for the correction of hypocalcemia, while the administration of 50, 000-80, 000 IU/day of VD2 were effective. The effects of VD2 supplementation on serum calcium concentration were dose-dependent, and the normalization of serum calcium concentrations was achieved more rapidly with higher dose of VD2. However, in the group treated with 80, 000 IU/day of VD2, many patients showed hypercalcemia, but in the group treated with 50, 000 IU/day of VD2i only a few patients showed it. From these results, suitable doses (initial and maintenance doses) of VD2 in Japanese dialysed patients will be 50, 000 lU/day. 2) When the responder group (normal serum calcium levels after 4 months of treatment with 50, 000 IU/day of VD2) and the non-responder group (less than 4.2 mEq/liter of serum calcium concentration on the same condition) were compared, the duration of dialysis were significantly shorter in the former than those in the latter. This fact may suggest that the effects of VD2 administration on hypocalcemia under chronic dialysis treatment are partly dependent on the residual renal function through the conversion of 25- (OH) -D3 into 1, 25 (OH2) D3.
