Reduction of trabecular and cortical volumetric bone mineral density at the proximal femur in patients with acromegaly

Objective: Data on dual energy absorptiometry (DXA)-measured bone mineral density (BMD) at the level of the total hip (TH) and femoral neck (FN) in patients with acromegaly (ACRO) are conflicting. Increase in bone size associated with ACRO may limit the reliability of DXA. Our objective is to evaluate trabecular and cortical volumetric BMD (vBMD) across the proximal femur in ACRO patients. Design: Cross sectional study in a clinical research center. Patients: Thirty-five ACRO patients (19 males; mean age, 48 +/- 7 years; BMI, 27.5 +/- 4.4 kg/m(2); 17 with active disease) and 35 age, gender, and BMI-matched controls. Results: vBMD was assessed by quantitative computed tomography at the level of the TH, FN, trochanter (TR), and intertrochanteric (IT). Trabecular vBMD was lower in both total and active ACRO as compared with controls (P< 0.01). Cortical vBMD was lower in ACRO patients (active and controlled) vs controls at both TH and TR sites (P< 0.05). These findings were confirmed when only eugonadal patients were analyzed. Both total cross sectional area (CSA) and average cortical thickness (ACT) were greater in ACRO patients vs controls (P<0.05). An inverse association between disease duration and trabecular vBMD at TH (r=-0.42, P=0.023) and IT (r=-0.41, P=0.026) was also found. Conclusion: Both cortical and trabecular vBMD are reduced at the proximal femur in ACRO patients, regardless of gender, gonadal status, and disease activity. Disease duration is negatively associated with trabecular vBMD at the TH and IT.