Bone metabolism in patients with newly diagnosed caeliac disease

Caeliac disease is an immune-mediated enteropathy induced by gluten in genetically predisposed individuals. Malabsorption of vitamins and minerals is a common finding in untreated patients and disturbance in bone metabolism is therefore a suspected complication. We wanted to assess vitamin D status, parathyroid hormone (PTH) and bone mineral density (BMD) in patients with newly diagnosed caeliac disease. Altogether 118 patients (93 females) were investigated. Median age was 42.5 years (range 20-87 years). Vitamin D metabolites, PTH and biochemical markers of bone metabolism were measured in blood. Lumbar spine, femoral neck and total body BMD were measured by dual x-ray absorptiometry (DXA); Z scores were obtained by comparison with locally derived age- and sex matched reference values. Vitamin D deficiency (25-hydroxyvitamin D < 30 nmol/l) was present in 20 % of the patients; 30 % of the patients had secondary hyperparathyroidism (PTH > or =7.0 pmol/l). BMD was significantly reduced (p < 0.001) at all skeletal sites measured. There was no relationship between vitamin D status and BMD, but PTH was negatively correlated to BMD at all skeletal sites (p < 0.005). Body mass index (BMI) was positively correlated to BMD in these patients (p < 0.001). Hypovitaminosis D and secondary hyperparathyroidism are common in patients with newly diagnosed caeliac disease in addition to low BMD.