Calcium regulating hormones and bone mineral content in patients after subtotal gastrectomy.

Twenty-nine men who had undergone Billroth I gastrectomy and 19 men who had undergone Billroth II gastrectomy were studied to examine the changes in their calcium regulating hormones and bone mineral content following surgery. The serum calcium and phosphate concentrations in the patients with Billroth I and Billroth II were normal. The Billroth II group had an elevated level of serum alkaline phosphatase and reduced bone mineral content. The 24,25(OH)2D concentration was reduced (P < 0.01) and 25(OH)D and 1,25(OH)2D concentrations were increased (P < 0.01, P < 0.05, respectively) in the Billroth II group. It was suggested by our study that the Billroth II patients had a reduced bone mineral content and an elevated 1,25(OH)2D concentration. Therefore, the pathophysiology of postgastrectomy bone metabolic disease is not due to vitamin D deficiency, but may instead be due to reduced calcium absorption in the intestine.