Table 2.
Baseline participant characteristics by quartile of percentage of total lean body mass among womena
| All | Percentage of Lean Body Mass Quartile 1 (37.3%-52.2%) | Percentage of Lean Body Mass Quartile 2 (52.3%-57.6%) | Percentage of Lean Body Mass Quartile 3 (57.6%- 62.2%) | Percentage of Lean Body Mass Quartile 4 (62.2%-86.6%) | P Value | |
|---|---|---|---|---|---|---|
| N | 984 | 201 | 240 | 229 | 314 | |
| Mean age at baseline (years) | 57.4 (17.3) | 60.1 (14.4) | 59.3 (15.7) | 57.5 (18.3) | 54.1 (18.9) | 0.0002 |
| Sex (% female) | 100 | 100 | 100 | 100 | 100 | |
| Race (% AA) | 24.5 | 34.8 | 25.0 | 26.2 | 16.2 | <0.0001 |
| Mean BMI (kg/m2) | 26.6 (3.6) | 31.3 (4.1) | 26.9 (3.1) | 24.4 (2.2) | 21.6 (2.0) | <0.0001 |
| Mean height (cm) | 162.3 (6.7) | 162.5 (6.7) | 162.0 (6.2) | 162.1 (6.7) | 162.7 (7.0) | 0.60 |
| Mean weight (kg) | 67.3 (13.1) | 82.8 (12.8) | 70.6 (10.3) | 64.0 (6.9) | 57.3 (6.9) | <0.0001 |
| Mean total lean mass (kg) | 39.0 (4.9) | 40.0 (5.5) | 38.9 (5.4) | 38.4 (4.1) | 38.9 (4.6) | 0.01 |
| Mean total fat mass (kg) | 25.8 (9.8) | 39.4 (7.8) | 29.3 (5.0) | 23.2 (3.2) | 16.3 (3.9) | <0.0001 |
| % Incident diabetes | 6.9 | 8.0 | 6.7 | 8.7 | 5.1 | 0.37 |
| Median follow-up time in years (IQR range) | 7 (1, 16) | 11 (3, 18) | 6 (1, 15) | 6 (1, 15) | 6 (1, 14) | 0.31 |
| Incidence rate of diabetes per 1000 person-years | 7.6 | 8.9 | 7.5 | 10.0 | 5.4 | 0.41 |
| Mean number of visits | 3.3 (2.5) | 3.3 (2.3) | 3.5 (2.9) | 3.2 (2.4) | 3.4 (2.4) | 0.51 |
| Knee extensor strength (Nm)b | 91.7 (30.9) | 93.0 (33.4) | 92.0 (29.7) | 91.4 (28.6) | 91.0 (28.6) | 0.82 |
| Leg lean mass (Right, kg) | 6.5 (1.1) | 6.7 (1.3) | 6.2 (1.2) | 6.4 (1.0) | 6.6 (1.1) | 0.08 |
| Knee extensor strength/leg lean mass (muscle quality; Nm/kg)b | 13.9 (3.8) | 13.6 (3.8) | 14.5 (3.3) | 13.9 (4.3) | 13.7 (3.9) | 0.39 |
| Mean A1C (%)c | 5.6 (0.4) | 5.7 (0.4) | 5.6 (0.4) | 5.6 (0.4) | 5.6 (0.5) | 0.10 |
| Mean fasting plasma glucose (mg/dL) | 93.5 (8.6) | 95.4 (8.6) | 94.7 (8.2) | 93.8 (9.6) | 91.0 (7.5) | <0.0001 |
| Mean 2-hour plasma glucose (mg/dL)d | 119.8 (33.8) | 128.4 (35.2) | 123.6 (35.5) | 118.3 (31.7) | 111.8 (31.3) | <0.0001 |
| % Prediabetes | 29 | 35 | 36 | 31 | 18 | <0.0001 |
Abbreviations: A1C, hemoglobin A1c; AA, African American; BMI, body mass index; DXA, dual x-ray absorptiometry; IQR, interquartile range; SD, standard deviation.
aQuartile ranges are defined based on DXA measures available at all visits. Mean (SD) shown unless otherwise indicated.
bn = 212 women with knee extensor strength assessed at their baseline visit.
cn = 237 women with A1C measured at their baseline visit.
dn = 691 women with 2-hour plasma glucose measured at their baseline visit.