Adipose tissue compartments, muscle mass, muscle fat infiltration, and coronary calcium in institutionalized frail nonagenarians

Abstract

Objective: to compare the different adipose tissue (AT) compartments, muscle mass, muscle fat infiltration, coronary calcium, as well as associations among changes in different AT compartments between frail and robust nonagenarians.

Materials and methods: Forty-two elderly subjects took part in this study: 29 institutionalized frail elderly (92.0 ± 8 years) and 13 robust elderly (88.2 ± 4.1 years). All patients underwent helical thoracic, abdominal and thigh computed tomography (CT). In addition, a non-enhanced prospectively ECG-triggered cardiac CT was performed to quantify the amount of coronary artery calcification and measure pericardial AT.

Results: The robust group presented significantly greater pericardial and abdominal AT volume, as well as greater axial and appendicular muscle size and high-density muscle tissue (greater muscle quality) than the frail group (P < 0.001), whereas no differences between groups were observed in coronary calcium. There were positive correlations between pericardial AT with visceral and subcutaneous AT values, as well as between pericardial AT and quadriceps, hamstrings, psoas and paravertebral low-density muscle tissues in the frail and robust groups (r = 0.57 to 0.91,P < 0.05).

Conclusions: Robust group presented greater muscle size and quality in the axial and appendicular muscles, as well as pericardial and abdominal AT area than the frail group.

Key points: • Robust nonagenarians presented more pericardial and abdominal AT volume than frail. • Frailty is associated with lower muscle size and high-density muscle tissue. • Muscle-fat infiltration shares analogous pattern of visceral and pericardial AT distribution.