Endocrine Abstracts

Objective: Growth hormone (GH) and insulin-like growth factor 1 (IGF-1) excess results in both reversible and irreversible damage to the skeleton, and includes increased vertebral fracture (VF) risk in the presence of normal BMD. The prevalence of VFs is approximately 60% in controlled acromegaly patients, and these VFs can progress during short-term follow-up. We aimed to identify the course of VFs and their associated risk factors in a cohort of acromegaly patients in long-term remission during long-term follow-up.

Methods: Thirty-one patients with acromegaly (49% female, median age 60 yrs (IQR 53–66)), who were in biochemical disease remission for a median of 12 years (IQR 7–17) following uni- or multimodality treatment, were included in this longitudinal, prospective, follow-up study. Spine radiographs of vertebrae Th4 to L4 were assessed for VFs using the Genant score, at baseline, after 2.6 yrs and 9.1 yrs of follow-up. Progression was defined as either a new fracture, or a ≥1-point increase in the Genant score.

Results: The prevalence of VF at the baseline visit was 87.1% (27/31 patients), and the number of VFs was associated with active disease duration (r = 0.462, P = 0.009). Progression of VFs was observed in eleven patients (35.5%), during the 9.1-year follow-up period, with a total incidence rate of 65.5 per 1,000 PY (Males 59.8/1,000 PY vs females 71.6/1,000 PY). VF progression occurred more frequently between baseline and the first follow-up visit, with an incidence rate of 86.9/1,000 PY, compared to the period between the first and second follow-up visit (incidence rate of 57.7/1,000 PY). Patients treated with surgery or radiotherapy had a higher risk of VF progression in this cohort in comparison with medical treatment (OR 17.3 (95% CI 1.5–203.7), P = 0.023).

Conclusions: In this cohort of long-term well-controlled acromegalic patients, the prevalence and progression of VFs was high, showing that deleterious effects of the transient GH and IGF-1 excess persist despite achievement of longstanding remission. Therefore, there is a clinical unmet need for strategies to prevent fractures in newly diagnosed and chronic patients with acromegaly.