Bone mineral and calcium metabolism before, during and after treatment of osteoporosis with 1 alpha-hydroxyvitamin D3 and calcium.

A series of osteoporotic patients treated for 25 months (average) with 1 alpha-hydroxyvitamin D3 (1 alpha-OHD3) supplemented with calcium were examined in respect of calcium metabolism and bone mineral changes before, during, and 12 months after cessation of treatment. The bone mineral content, which increased during treatment, showed a decreasing post-treatment tendency. The decrease was more obvious in patients with senile osteoporosis. The levels of serum calcium and phosphate stayed within normal levels. The urinary calcium excretion rate, which also rose during treatment, returned to pre-treatment values after discontinuing treatment. Excretion of urinary phosphate, however, showed a tendency towards further decrease. Serum PTH stayed within normal levels, while serum alkaline phosphatase, which was depressed during treatment, rose again after treatment. The investigation speaks in favour of a continuous administration of 1 alpha-OHD3 and calcium which is generally noted to increase bone mineral during long-term treatment.