Reduction in Serum Alkaline Phosphatase Levels by Treatment with Active Vitamin D (Alphacalcidol) in Primary and Secondary Hyperparathyroidism and in Euparathyroid Individuals

Abstract

Raised levels of alkaline phospatases (ALP) are seen in conditions with a high bone turn-over, such as in primary and secondary hyperparathyroidism (HPT). To study the effects of active vitamin D treatment on ALP, alphacalcidol (1-alpha-hydroxy-vitamin D₃), was given to patients with primary HPT as well as HPT secondary to chronic renal failure and also to healthy, euparathyroid subjects. Oral alphacalcidol (1 μg daily) significantly reduced serum ALP (3.2 ± 1.1 to 2.8 ± 1.2 μkat/l, p<0.05) in a 6-month double-blind, placebo-controlled study in patients with mild primary HPT, and alphacalcidol given intravenously to uremic subjects induced a reduction in serum ALP levels (3.5 ± 3.1 to 2.6 ± 1.7 μkat/l, p<0.05) during a 4 month's study. A reduction in serum ALP was also seen in the euparathyroid subjects (2.4 ± 0.77 to 2.2 ± 0.64 μkat/l, p=0.03). This study indicates that treatment with active vitamin D is effective in reducing the increased bone turnover seen in subjects with both primary and secondary HPT.