Associations of calf inter- and intra-muscular adipose tissue with cardiometabolic health and physical function in community-dwelling older adults

OBJECTIVES: To determine associations of inter- and intra-muscular adipose tissue (IMAT) with cardiometabolic health and physical function in older adults. METHODS: 48 community-dwelling older adults aged =/>65 years (mean 71.6+/-4.8 years; 52 women) underwent whole-body dual-energy X-ray absorptiometry, to assess appendicular lean mass (ALM), and peripheral quantitative computed tomography (pQCT; 66 tibia), to assess calf IMAT cross-sectional area ([CSA]; cm(2)) and muscle density (mg/cm(3); higher values indicate lower fat infiltration). Fasting glucose, lipids, triglycerides and C-reactive protein (CRP) were analysed. Physical function was assessed by postural sway (computerised posturography; N=41), and gait analysis (GAITRite Electronic Walkway; N=40). RESULTS: Higher IMAT CSA and muscle density were associated with significantly higher (B=0.85 95 CI [0.34, 1.36]) and lower (-2.14 [-4.20, -0.08]) CRP and higher (0.93 [0.56, 1.30]) and lower postural sway (-3.12 [-4.74, -1.50]), respectively, after adjustment for age, sex and ALM/BMI. Higher IMAT CSA was associated with slower gait speed and cadence, and greater step time and step width (all P