Prevalence of cortical osteoporosis in mild and severe primary hyperparathyroidism and its relationship with bone markers and vitamin D status.

Studies on the prevalence of site-specific osteoporosis in patients with different clinical presentations of primary hyperparathyroidism (PHPT) are scarce in the literature. The present study aims to determine the prevalence of cortical osteoporosis in such patients by using 3-site dual-energy X-ray absorptiometry (lumbar spine, femoral neck, 1/3 radius). We studied 49 patients, 12 males and 37 females, with PHPT, who were separated into 3 groups: asymptomatic (AS), renal stone disease (RS), and osteitis fibrosa cystica (OF). Osteoporosis occurred as follows: lumbar spine-48% for AS, 17.6% for RS, and 100% for OF (p=0.0004); femoral neck-20% for AS, 12% for RS, and 85.7% for OF (p=0.0014); 1/3 radius-71% for AS, 53% for RS, and 86% for OF (p=0.2845). Serum calcium, parathyroid hormone, alkaline phosphatase, and beta-carboxy-terminal telopeptide were significantly higher in the OF group. The mean values for 25-hydroxyvitamin D were lower in OF group than AS and RS groups (15.2+/-6.3 ng/mL vs. 22.7+/-11.9 ng/mL and 20.3+/-7.0 ng/mL; p=0.2139). Based on these results, we conclude that the prevalence of osteoporosis is high in all sites studied and is almost universal in the OF patients. The great prevalence of cortical osteoporosis is seen even in young patients with less severe forms of the disease.