Cross-sectional studies showed an elevated prevalence of clinical and morphometric vertebral fractures (VFs) in adult patients with growth hormone deficiency (GHD). However, no data are available on incidence and determinants of radiological VFs in this clinical setting. In this prospective study, we investigated the incidence and risk factors of radiological VFs in adults with GHD. Forty patients with GHD (28 males, 12 females; median age 44 years, range 19-82) were studied for incident VFs using quantitative morphometric approach on spine X-ray at baseline and after 6 years of follow-up. GHD patients were also studied for bone mineral density (BMD) measured by DXA at lumbar spine. After 6 years of follow-up, 12 patients (30 %) experienced incident VFs. Patients with incident VFs had more frequently untreated GHD and prevalent VFs at baseline, as compared to patients who did not experience incident VFs. Untreated GHD patients were significantly older as compared to treated GHD (50 years, range 19-82 vs. 36 years, range 19-75; p = 0.003), but the correlation between high risk of VFs and untreated GHD remained significant even after adjustment for the age of patients (odds ratio 6.8, CI 95 % 1.1-41.8; p = 0.037). In GHD patients experiencing incident VFs, lumbar spine BMD decreased significantly whereas it did not change in patients not developing VFs. This is the first prospective study confirming the hypothesis suggested by cross-sectional studies that untreated GHD may cause high risk of VFs in adult patients and that recombinant human GH treatment may effectively decrease such a risk.
Keywords: Bone mineral density; Growth hormone deficiency; IGF-I; Osteoporosis; Vertebral fractures.