Table 1. Anthropometric characteristics and measurement results of paraspinal muscles and IMAT in 516 healthy Chinese women according to age by decade.
| Variable | 20–29 years (n=69) | 30–39 years (n=127) | 40–49 years (n=140) | 50–59 years (n=88) | 60–69 years (n=67) | 70–79 years (n=25) | P | Age*BMI interaction (P) |
|---|---|---|---|---|---|---|---|---|
| Age (years) | 26.84±2.03 | 34.39±2.88 | 44.21±2.61 | 54.08±3.04 | 63.60±2.72 | 74.16±2.70 | ||
| Height (m) | 161.88±4.85 | 161.28±6.60 | 160.63±6.42 | 159.85±5.93 | 158.13±5.26 | 153.92±5.51 | <0.001 | |
| Weight (kg) | 59.63±9.07 | 61.78±11.71 | 62.91±10.23 | 63.19±8.48 | 65.58±10.13 | 62.12±9.26 | 0.001 | |
| BMI (kg/m2) | 22.77±3.43 | 23.71±3.97 | 24.40±3.87 | 24.75±3.18 | 26.21±3.79 | 26.28±4.17 | <0.001 | |
| CSAIMAT (cm2) | 3.00±1.70 | 3.36±2.18 | 4.26±2.33 | 5.54±2.17 | 8.26±3.50 | 11.06±4.56 | — | 0.001 |
| CSAmuscle (cm2) | 38.46±6.33 | 40.02±6.88 | 39.62±6.43 | 38.59±7.39 | 35.56±5.26 | 30.86±5.37 | <0.001 | 0.174 |
| IMAT% (%) | 7.29±4.60 | 7.63±3.41 | 9.68±4.96 | 12.75±5.42 | 18.57±6.16 | 25.84±7.55 | <0.001 | 0.071 |
Data are expressed as mean ± SD. P by Kruskal-Wallis test for changes across age groups. BMI, body mass index; IMAT, Intermuscular adipose tissue; CSA, cross-sectional area. IMAT% referred to CSAIMAT / (CSAIMAT + CSAmuscle) as fatty infiltration ratio of muscle.