Elevated PTH levels in hypovitaminosis D are more rapidly suppressed by the administration of 1,25-dihydroxy-vitamin D3 than by vitamin D3.

OBJECTIVE

To assess markers of bone metabolism in two groups of inpatients with hypovitaminosis D and elevated PTH levels receiving two different vitamin D medications.

METHODS

26 patients with secondary hyperparathyroidism (2 degrees HP) were treated either with 800 IU cholecalciferol and 1000 mg calcium or 0.5 microgram calcitriol plus 500 mg calcium daily for 6 months. 25-OH-vitamin D3, 1,25-dihydroxy-vitamin D3, intact PTH, calcium and urinary N-telopeptides of bone collagen I were measured at baseline, 3 and 6 months.

RESULTS

PTH levels decreased earlier in the calcitriol group than in the cholecalciferol group. After six month no difference could be documented. Lowering of urinary N-telopeptides excretion was observed in both groups.

CONCLUSION

The use of both forms of vitamin D supplementation appears to be useful for patients with hypovitaminosis D, elevated PTH levels and high telopeptide excretion.