Natural History Study of Albright Hereditary Osteodystrophy: Includes Substudies on Effects of Growth Hormone in Patients With Pseudohypoparathyroidism Type 1A and Cognitive & Behavioral Studies in Albright Hereditary Osteodystrophy

Pseudohypoparathyroidism type 1A (PHP1A) is a disorder that causes many endocrine and developmental problems. To date, medical treatment has focused primarily on maintenance of normal serum levels of calcium, phosphorous, and thyroid hormone. However, these therapeutic interventions do not address the problems of short stature, obesity, and subcutaneous ossifications, which for many are a source of considerable morbidity and personal distress. These patients require frequent medical care, blood tests, and medication adjustments. PHP1A is an inherited condition with an estimated prevalence in the United States of 1:15,000- 20,000, and the studies that we propose provide an opportunity to improve the quality of life in affected patients. We have found that growth hormone (GH) deficiency is common in these patients, and our data suggest that GH testing should be part of their routine standard of care. We have been investigating whether GH treatment can increase final adult height and also whether GH treatment can reduce weight and improve a variety of metabolic disturbances and overall health in both children and adults.

GH deficiency not only leads to short stature and obesity, but also to osteoporosis, hyperlipidemia, depressed cardiac and renal function, as well as an overall lack of energy. It is quite possible that treatment of GH-deficient patients with PHP1A could improve any or all of the above problems. GH treatment has been FDA approved for use in both children and adults with GH deficiency. Therefore, it may be possible to provide improvement in health and overall quality of life in these patients.

Additionally, we completed a study in which we treated children with PHP1A who are not GH deficient (i.e., GH sufficient). The rationale is that GH treatment could maximize linear growth velocity prior to the premature bone fusion that occurs in this condition and potentially improve final adult height. The supply of growth hormone has ended for this study, and we are following those participants who were in this study and received the growth hormone supply. Some of these patients remain on growth hormone as per clinical care secondary to their responses.

This study also seeks to define the specific neurocognitive and psychosocial disabilities in individuals with AHO in order to develop therapies and improve quality of life. AHO includes two subtypes: pseudohypoparathyroidism type 1A (PHP1A) and pseudopseudohypoparathyroidism (PPHP).