Table 2.
Factors associated with low IGF-1 levels (below the median) in univariate logistic regressions.
| IGF-1 levels | IGF-1 levels | OR (95% CI) | p value | |
|---|---|---|---|---|
| below the median | above the median | |||
| Age (years) | 56 [48; 64] | 49 [41; 59] | <0.0001 | |
| Q2 vs. Q1 | 1.70 (1.11; 2.61) | 0.0143 | ||
| Q3 vs. Q1 | 3.50 (2.30; 5.33) | <0.0001 | ||
| Q4 vs. Q1 | 4.23 (2.76; 6.48) | <0.0001 | ||
| Male gender (%) | 62.5 | 65.2 | 0.90 (0.67; 1.21) | 0.5003 |
| Anthropometric markers | ||||
| BMI (kg/m2)* | 30.8 [27.0; 34.9] | 29.1 [25.1; 33.9] | <0.0001 | |
| Q2 vs. Q1 | 1.66 (1.08; 2.55) | 0.0199 | ||
| Q3 vs. Q1 | 1.83 (1.20; 2.80) | 0.0051 | ||
| Q4 vs. Q1 | 2.83 (1.82; 4.41) | <0.0001 | ||
| Waist circumference (cm)* | 109.0 [100.0; 119.0] | 104.0 [93.0; 114.0] | <0.0001 | |
| Q2 vs. Q1 | 2.09 (1.29; 3.38) | 0.0026 | ||
| Q3 vs. Q1 | 2.25 (1.40; 3.63) | 0.0009 | ||
| Q4 vs. Q1 | 3.01 (1.85; 4.89) | <0.0001 | ||
| Sleep apnea severity | ||||
| AHI (events/hour)* | 30.0 [18.0; 49.0] | 22.0 [10.7; 35.0] | <0.0001 | |
| Q2 vs. Q1 | 1.02 (0.65; 1.61) | 0.9304 | ||
| Q3 vs. Q1 | 1.80 (1.14; 2.84) | 0.0116 | ||
| Q4 vs. Q1 | 3.03 (1.88; 4.88) | <0.0001 | ||
| Epworth score* | 9 [5; 12] | 9 [6; 13] | 0.7535 | |
| Q2 vs. Q1 | 1.20 (0.77; 1.87) | 0.4168 | ||
| Q3 vs. Q1 | 1.28 (0.82; 2.00) | 0.2843 | ||
| Q4 vs. Q1 | 1.18 (0.75; 1.86) | 0.4658 | ||
| Plasma glucose and lipid profile | ||||
| Glucose (mg/dL) | 101 [92; 114] | 96 [90; 105] | 1.33 (0.97; 1.82) | 0.0775 |
| Total cholesterol (g/L) | 2.08 [1.78; 2.34] | 2.01 [1.73; 2.26] | 1.36 (1.01; 1.84) | 0.0444 |
| HDL-c (g/L) | 0.51 [0.42; 0.61] | 0.50 [0.42; 0.61] | 0.68 (0.26; 1.77) | 0.4286 |
| LDL-c (g/L) | 1.25 [0.98; 1.48] | 1.22 [1.01; 1.44] | 1.30 (0.96; 1.75) | 0.0928 |
| Triglycerides (g/L) | 1.35 [0.95; 1.91] | 1.14 [0.79; 1.60] | 1.36 (1.13; 1.62) | 0.0008 |
Data are reported as median [interquartile range] for continuous variables and by percentage for qualitative variables in the subgroups of participants having IGF-1 below or above the median. Univariate logistic regressions with IGF-1 levels as dependent variable are reported by Odd ratios (95% CI) and are adjusted for age and gender. BMI, body mass index; Q, quartile; AHI, apnea+hypopnea index.