Osteosarcopenia in acromegaly: reduced muscle quality and increased vertebral fat deposition

PURPOSE

Musculoskeletal disorders are among the most disabling comorbidities in patients with acromegaly. This study examined muscle and bone quality in patients with acromegaly.

METHODS

Thirty-three patients with acromegaly and nineteen age- and body mass index-matched healthy controls were included in the study. Body composition was determined using dual-energy X-ray absorptiometry. The participants underwent abdominal magnetic resonance imaging (MRI) for cross-sectional evaluation of muscle area and vertebral MRI proton density fat fraction (MRI-PDFF). Muscular strength was measured using hand grip strength (HGS). Skeletal muscle quality (SMQ) was classified as weak, low, or normal, according to HGS/ASM (appendicular skeletal muscle mass) ratio.

RESULTS

Groups had similar lean tissues, total body fat ratios, and total abdominal muscle areas. Acromegalic patients had lower pelvic BMD (p = 0.012) and higher vertebral MRI-PDFF (p = 0.014), while total and spine bone mineral densities (BMD) were similar between the groups. The SMQ score rate was normal only 57.5% in the acromegaly group, and 94.7% of the controls had a normal SMQ score (p = 0.01). Subgroup analysis showed that patients with active acromegaly (AA) had higher lean tissue and lower body fat ratios than controlled acromegaly (CA) and control groups. Vertebral MRI-PDFF was higher in the CA group than that in the AA and control groups (p = 0.022 and p = 0.001, respectively). The proportion of participants with normal SMQ was lower in the AA and CA groups than that in the control group (p = 0.012 and p = 0.013, respectively).

CONCLUSION

Acromegalic patients had reduced SMQ and pelvic BMD, but greater vertebral MRI-PDFF. Although lean tissue increases in AA, this does not affect SMQ. Therefore, increased vertebral MRI-PDFF in controlled acromegalic patients may be due to ectopic adiposity.

The feasibility of T2 mapping in the assessment of hepatic steatosis, inflammation, and fibrosis in patients with non-alcoholic fatty liver disease: a preliminary study

AIM

To determine the feasibility of magnetic resonance imaging T2 mapping in the quantification of liver steatosis in patients with biopsy-proven non-alcoholic fatty liver disease (NAFLD), and to assess the effect of inflammation and fibrosis on T2 values of the liver.

MATERIAL AND METHODS

Twenty-three consecutive patients with biopsy-proven NAFLD who underwent T2 mapping between December 2013 and September 2014 were included in this study. All patients underwent fast spin echo multi-echo sequence with eight echoes for T2 measurements.

RESULTS

The mean liver T2 value and percentage of histological steatosis was 64.9 ± 7.4 ms and 46.5 ± 27.6%, respectively. There was a good correlation between the liver T2 value and histology-determined steatosis (r = 0.780, p<0.001) and grade of steatosis (r_s = 0.779, p<0.001). The mean T2 value in patients with definitive non-alcoholic steatohepatitis (NASH) was significantly higher in comparison with patients without NASH (69 ± 7.37 versus 61.73 ± 5.99 ms, p=0.016). The correlation between T2 value and NAFLD activity score (NAS) was significant (r_s = 0.443, p=0.034); however, the correlation disappeared after adjustment for hepatic steatosis and fibrosis (r=0.131, p=0.572). There was a close inverse correlation between T2 value and fibrosis stage after adjusting for hepatic steatosis (r=-0.536, p=0.012).

CONCLUSION

T2 mapping can be used for quantification of hepatic steatosis, as there is a close correlation between T2 relaxation values and histology-determined steatosis. Patients with definite NASH have increased T2 values and there is an inverse correlation between the T2 value and fibrosis stage of the liver. T2 mapping in NAFLD may be a useful clinical tool for disease assessment and prognostication.