Table 1.
Baseline Characteristics Dichotomized for High and Low Responders by Change in Lean Body Mass
| Variable (N=108) | High responders* (N=56) | Low responders* (N=52) | P-value |
|---|---|---|---|
| Week 17 Δ ≥ 1.5 kg | Week 17 Δ < 1.5 kg | ||
| Age, yrs | 71±4 | 71±4 | 0.54 |
| BMI, kg/m2 | 28.0±3.6 | 27.2±2.9 | 0.22 |
| Non-Hispanic Caucasian | 50 (89%) | 43 (83%) | 0.32 |
| On treatment for hypertension | 14 (25%) | 14 (27%) | 0.82 |
| History of Smoking | 20 (36%) | 19 (37%) | 0.93 |
| History of elevated cholesterol† | 8 (14%) | 5 (10%) | 0.46 |
| History ischemic heart events | 18 (32%) | 19 (37%) | 0.63 |
| Daily food intake | |||
| Caloric intake kcal/day | 2166±503 | 2242±464 | 0.42 |
| Protein g/kg/day | 1.09±0.34 | 1.14±0.32 | 0.42 |
| Carbohydrate g/day | 263±86 | 255±73 | 0.59 |
| Fat g/day | 88±53 | 88±28 | 0.96 |
| Systolic blood pressure mmHg | 129±14 | 137±19 | 0.01 |
| Diastolic blood pressure mmHg | 75±9 | 79±8 | 0.02 |
| Activity and Quality of Life | |||
| PASE‡ Score | 145±62 | 145±55 | >0.99 |
| Geriatrics Depression Score | 3.1±3.4 | 2.5±2.9 | 0.31 |
| SF-12 Physical Component Score | 52±6 | 53±5 | 0.36 |
| SF-12 Mental Component Score | 56±6 | 56±6 | 0.62 |
| Serum creatinine umol/L | 76.3±15.3 | 76.3±7.6 | 0.53 |
| Albumin g/L | 41±3 | 41±3 | 0.71 |
| Hematocrit % | 43.2±2.7 | 43.2±2.8 | 0.90 |
| Prostate Specific Antigen ug/L | 1.6±0.9 | 1.3±0.8 | 0.08 |
| Blood Lipids | |||
| Triglycerides mmol/L | 1.47±0.75 | 1.39±0.63 | 0.55 |
| Total cholesterol mmol/L | 4.56±0.75 | 4.45±0.73 | 0.46 |
| LDL cholesterol mmol/L | 1.17±0.31 | 1.06±0.34 | 0.16 |
| HDL cholesterol mmol/L | 2.72±0.70 | 2.75±0.65 | 0.95 |
| Hormones: | |||
| Total testosterone§, ηmol/L | 11.9±3.6 | 13±3 | 0.09 |
| IGF-1, nmol/L | 14.1±4.3 | 25±3.3 | 0.54 |
| QUICKI | 0.161±0.017 | 0.161±0.015 | 0.87 |
| Body Composition: | |||
| Lean body mass, kg | 58±7 | 59±7 | 0.43 |
| Appendicular lean mass, kg | 25±3 | 26±3 | 0.26 |
| Total adipose tissue mass, kg | 23.5±7.3 | 20.7±5.9 | 0.03 |
| Trunk fat mass, kg | 13.2±4.3 | 11.9±3.7 | 0.09 |
| Cardiovascular characteristics: | |||
| VO2 peak ml/kg/min | 24.6±4.9 | 24.9±4.8 | 0.73 |
| Aerobic endurance time sec | 308±102 | 359±135 | 0.051 |
| Framingham 10 year risk score % | 13.7±1.3 | 14±1.2 | 0.27 |
Baseline characteristics were dichotomized by total lean body mass (LBM), appendicular skeletal muscle mass (ASMM), total fat and trunk fat. Because dichotomized results were only minimally different for the four body composition parameters due to slightly different sample sizes created by their respective median splits, the dichotomized groups are only shown for total LBM.
Based on past or current treatment for elevated cholesterol
Physical Activity Scale for the Elderly
Screening testosterone levels for eligibility were determined by immunoassay in the local university clinical laboratories
Conversion to non-SI units: divide triglycerides by 0.0113 (mg/dL); total cholesterol (C), LDL-C, and HDL-C by 0.0259 (mg/dL); testosterone by 0.0347 (ηg/dL); and IGF-1 by 0.131 (ηg/mL)