Bone loss in celiac disease is related to secondary hyperparathyroidism

Celiac disease is a major cause of intestinal malabsorption. Previous studi es have demonstrated that celiac disease is associated with significant ost eoporotic bone loss. These studies have suggested that successful treatment of the malabsorption is associated with amelioration of the bone loss, Suc h studies have failed to examine bone mass at peripheral skeletal sites whi ch is more likely to be responsive to changes in parathyroid hormone (PTH) in response to calcium malabsorption. We hale examined bone density in the lumbar spine, femoral neck, and distal forearm in 35 patients with celiac d isease who had been established on gluten free diet. In addition, the conce ntrations of PTH and 1,25-dihydroxyvitamin D (1,25(OH)(2)D) were measured. Bone density was below that expected for the subject's age and gender at al l, sites. This was most marked in the distal forearm where the bone density was 1.40 SD before expected (p < 0.0001). In the forearm, there was a nega tive relationship between bone density and PTH concentration (r = -0.49, p = 0.009), in the forearm and lumbar spine, there was a negative relationshi p between 1,25(OH)(2)D concentration and bone density. Bone mass ass not re lated to the concentration of 25-hydroxyvitamin D at any of the skeletal si tes measured. Bone density is reduced in the peripheral skeleton in celiac disease and this deficit persists despite treatment with apparent normaliza tion at axial skeletal sites. This reduction in bone mass is related to the presence of secondary hyperparathyroidism which should be sought in all pa tients with treated celiac disease.