Endocrine Abstracts

GH excess is considered as one of the causes of secondary osteoporosis with an increased risk of vertebral fractures in men and post-menopausal women with acromegaly. GH excess in acromegaly is also frequently associated with type 2 diabetes which is considered as a risk factor for fragility fractures in the general population. In this cross-sectional study, we evaluated whether type 2 diabetes may influence the prevalence vertebral fractures in acromegaly. Fifty-seven males with acromegaly (median age 47 years, range: 24–85) and 57 control males were evaluated for bone mineral density (BMD) by lumbar DXA and for vertebral fractures by a radiological and morphometric approach. Seventeen acromegalic patients were affected by type 2 diabetes. The prevalence of vertebral fractures was higher in acromegalic patients as compared with the control subjects (52.6 vs 10.5%; P<0.001). Acromegalic patients with fractures had serum IGF1 values significantly higher, and the duration of active disease significantly longer than those found in patients who did not fracture. The prevalence of fractures was significantly higher in acromegalic patients with diabetes as compared to those without diabetes (76.5 vs 42.5%; P=0.02), without significant difference in BMD-Z-score at lumbar spine. No significant difference in prevalence of vertebral fractures was observed between patients with controlled and those with uncontrolled diabetes. In the multivariate regression analysis, the correlation between diabetes and vertebral fractures was independent of activity of acromegaly (odds ratio 5.8, 95% CI 1.4–23.5; P=0.01). In conclusion, this study suggests that type 2 diabetes mellitus may be an adjunctive risk factor for vertebral fractures in men with acromegaly according to the hypothesis that GH hypersecretion and insulin resistance may exert synergic negative effects on the skeleton. On clinical point of view, our results would suggest to perform a strict skeletal monitoring of acromegalic patients with type 2 diabetes.