3D DXA Hip Differences in Patients with Acromegaly or Adult Growth Hormone Deficiency

Abstract

The skeleton is regulated by and responds to pituitary hormones, especially when the circulating levels are perturbed in disease. This study aims to analyse the between-group differences in 3D dual-energy X-ray absorptiometry (DXA) parameters at the hip site among patients with acromegaly or adult growth hormone deficiency (AGHD) and a healthy control group. The current cross-sectional study includes data for 67 adults, 20 with acromegaly, 14 with AGHD and 33 healthy controls. We obtained the areal bone mineral density (aBMD) outcomes using DXA and cortical and trabecular parameters using 3D-DXA software (3D-SHAPER). The mean-adjusted 3D-DXA parameters did not differ between acromegaly patients and the controls (p > 0.05); however, we found cortical bone impairment (-7.3% to -8.4%; effect size (ES) = 0.78) in AGHD patients (p < 0.05). Differences in the cortical bone parameters were more evident when comparing AGHD patients (-8.5% to -16.2%; ES = 1.22 to 1.24) with acromegaly patients (p < 0.05). In brief, the 3D mapping highlighted the trochanter as the site with greater cortical bone differences between acromegaly patients and the controls. Overall, AGHD patients displayed lower cortical parameters at the trochanter, femoral neck and intertrochanter compared to the controls and acromegaly patients. To sum up, 3D-DXA provided useful information about the characteristics of bone involvement in growth hormone (GH)-related disorders. Patients with AGHD showed distinct involvement of the cortical structure.

Keywords: DXA; bone QCT/microCT; bone modelling and remodelling; osteoporosis.

Figure 1

Adjusted differences (%) (by age, sex and body mass index) in (A) the areal bone mineral density (aBMD, g/cm²) and (B) 3D-DXA parameters between patients with acromegaly (n = 20), adult growth hormone deficiency (AGHD, n = 14) and the healthy control group (n = 33). * p < 0.05 and ^¥ p < 0.09 relative to the control group.

Figure 2

Distribution of the average differences (p < 0.05) in (A1–A3) the cortical surface bone mineral density (cortical sBMD), (B1–B3) cortical volumetric bone mineral density (cortical vBMD) and (C1–C3) cortical thickness of the total femur region among groups: acromegaly (n = 20), adult growth hormone deficiency (AGHD, n = 14) and the healthy control group (n = 33). Regions with no significant differences are coloured in grey (p > 0.05).