Table 2.
Determinants of total ghrelin, growth hormone, total IGF-1, and IGFBP-3 baseline concentrations
| Total ghrelin (pg/mL) | Growth hormone (pg/mL) (log10–transformed) | Total IGF–1 (ng/mL) | IGFBP–3(μg/mL) | |
|---|---|---|---|---|
| Explained variance (global P value) | R 2 = 0.50 P < .0001 | R 2 = 0.44 P = .0005 | R2 = 0.23 P = .14 | R2 = 0.20 P = .16 |
| Age (years) | –0.68 ± 3.5(–7.74, 6.39); partial r: 0.03; P value: 0.85 | 0.01 ± 0.01 (–0.01, 0.02); partial r: 0.18; P value: 0.26 | –0.85 ± 0.5 (–1.86, 0.16); partial r: 0.26; P value: 0.10 | –0.01 ± 0.01 (–0.02, 0.01); partial r: 0.16; P value: 0.30 |
| Sex (male) | –227.19 ± 108.17(–445.8, –8.58); partial r: 0.32; P value: .04 | –0.82 ± 0.19 (–1.22, –0.43); partial r: 0.56; P value: .0001 | 11.74 ± 15.69 (–19.99, 43.48); partial r: 0.12; P value: .46 | –0.22 ± 0.19 (–0.61, 0.18); partial r: 0.17; P value: .27 |
| Ethnicity (Native American) | 43.84 ± 108.73 (–175.92, 263.59); partial r: 0.06; P value: .69 | 0.53 ± 0.2 (0.13, 0.92); partial r: 0.39; P value: .01 | 0.65 ± 15.97 (–31.65, 32.95); partial r: 0.01; P value: .97 | 0.04 ± 0.2(–0.35, 0.44); partial r: 0.03; P value: .83 |
| Ethnicity (White) | 390.87 ± 115.26 (157.92, 623.81); partial r: 0.47; P value: .002 | 0.46 ± 0.21 (0.04, 0.87); partial r: 0.33; P value: .03 | 19.61 ± 17.04 (–14.86, 54.07); partial r: 0.18; P value: .26 | 0.35 ± 0.21 (–0.07, 0.77); partial r: 0.26; P value: .10 |
| Ethnicity (Black) | 227.11 ± 121.95(–19.35, 473.57); partial r: 0.28; P value: .07 | 0.46 ± 0.22(0.02, 0.9); partial r: 0.31; P value: .04 | 16.1 ± 18 (–20.33, 52.47); partial r: 0.14; P value: .38 | 0.03 ± 0.22(–0.41, 0.47); partial r: 0.02; P value: .90 |
| Percentage body fat | –4.26 ± 4.88 (–14.13, 5.61); partial r: 0.14; P value: .39 | –0.02 ± 0.01(–0.04, 0); partial r: 0.37; P value: .02 | 0.32 ± 0.7 (–1.1, 1.73); partial r: 0.07; P value: .65 | –0.01 ± 0.01(–0.02, 0.01); partial r: 0.12; P value: .44 |
| Intercept | 723.36 ± 238.14 (242.06, 1204.65); P value: .004 | 2.52 ± 0.43 (1.65, 3.38); P value: <.0001 | 55.25 ± 40.92 (–27.52, 138.02); P value: .18 | 2.29 ± 0.43 (1.42, 3.15); P value: <.0001 |
Multivariate models for the determinants of overnight-fasted values of total ghrelin, growth hormone, total IGF-1, and IGFBP-3 (average of prechamber values). A multivariate analysis with body mass index instead of percentage body fat as covariate yielded similar results. Similar results were also obtained when additionally including storage time in the multivariate model with total IGF-1 as dependent variable. The β coefficient estimate in each cell is reported with ± SE and 95% CI in parentheses, along with partial correlations and P value. Significant results are highlighted in bold.
Abbreviations: IGF-1, insulin-like growth factor 1; IGFBP-3, IGF-binding protein 3.