Isolated GH deficiency due to a GHRH receptor mutation causes hip joint problems and genu valgum, and reduces size but not density of trabecular and mixed bone

J Clin Endocrinol Metab. 2013 Nov;98(11):E1710-5. doi: 10.1210/jc.2013-2349. Epub 2013 Sep 20.

Abstract

Context: The GH/IGF-I axis is important for bone growth, but its effects on joint function are not completely understood. Adult-onset GH-deficient individuals have often reduced bone mineral density (BMD). However, there are limited data on BMD in adult patients with untreated congenital isolated GH-deficient (IGHD). We have shown that adult IGHD individuals from the Itabaianinha, homozygous for the c.57+1G>A GHRHR mutation, have reduced bone stiffness, but BMD and joint status in this cohort are unknown.

Objective: The goal is to study BMD, joint function, and osteoarthritis score in previously untreated IGHD adults harboring the c.57+1G>A GHRHR mutation.

Design: This is a cross-sectional study.

Methods: Areal BMD by dual-energy X-ray absorptiometry was measured in 25 IGHD and 23 controls (CO). Volumetric BMD (vBMD) was calculated at the lumbar spine and total hip. Joint function was assessed by goniometry of elbow, hips, and knees. X-rays were used to measure the anatomic axis of knee and the severity of osteoarthritis, using a classification for osteophytes (OP) and joint space narrowing (JSN).

Results: Genu valgum was more prevalent in IGHD than CO. The osteoarthritis knees OP score was similar in both groups, and knees JSN score showed a trend to be higher in IGHD. The hips OP score and JSN score were higher in IGHD. Areal BMD was lower in IGHD than CO, but vBMD was similar in the two groups. Range of motion was similar in elbow, knee, and hip in IGHD and CO.

Conclusions: Untreated congenital IGHD due to a GHRHR mutation causes hip joint problems and genu valgum, without apparent clinical significance, reduces bone size, but does not reduce vBMD of the lumbar spine and hip.

MeSH terms

  • Absorptiometry, Photon
  • Adult
  • Bone Density
  • Cross-Sectional Studies
  • Dwarfism, Pituitary / diagnostic imaging
  • Dwarfism, Pituitary / epidemiology
  • Dwarfism, Pituitary / genetics*
  • Female
  • Genu Valgum / diagnostic imaging
  • Genu Valgum / epidemiology
  • Genu Valgum / genetics*
  • Hip Joint / diagnostic imaging
  • Hip Joint / pathology
  • Homozygote
  • Humans
  • Insulin-Like Growth Factor I / metabolism
  • Male
  • Middle Aged
  • Models, Biological
  • Osteoarthritis, Hip / diagnostic imaging
  • Osteoarthritis, Hip / epidemiology
  • Osteoarthritis, Hip / genetics*
  • Osteoarthritis, Knee / diagnostic imaging
  • Osteoarthritis, Knee / epidemiology
  • Osteoarthritis, Knee / genetics*
  • Point Mutation
  • Prevalence
  • Receptors, Neuropeptide / genetics*
  • Receptors, Pituitary Hormone-Regulating Hormone / genetics*
  • Young Adult

Substances

  • Receptors, Neuropeptide
  • Receptors, Pituitary Hormone-Regulating Hormone
  • Insulin-Like Growth Factor I
  • somatotropin releasing hormone receptor