Does parathyroid hormone control bone quality?

Excerpt

The article in this issue of Endocrine by Cipriani and colleagues from Columbia University in New York contrasts the effects of restoring toward normal the parathyroid hormone (PTH) levels in two cohorts of patients: one with primary hyperparathyroidism and the other with hypoparathyroidism [1]. Patients in these two groups approach the euparathyroid state from two vastly different places as regards bone mass and microarchitecture and levels of formation/resorption and cellular activity. Over the last two decades, this team of investigators led by Drs. Bilezikian, Silverberg and Rubin have tenaciously gone after the question of how PTH mediates changes in skeletal mass and structure and more elusive properties of the mineral and matrix components of bone that comprise its “quality” using primary hyperparathyroidism and hypoparathyroidism as model systems. Their efforts first focused on defining the clinical, biochemical, and densitometric hallmarks of primary hyperparathyroidism—a condition mainly seen today in a mild and asymptomatic form, sometimes presenting as the normocalcemic variant. Observations from their 15-year cohort study of 116 patients [2] shaped our current Guideline for assessing and managing patients with this disorder [3]. …