Table 2.
Descriptive Statistics, Cut Points, and Correlations Between System-Level and Allostatic Load Scores
| Biomarkers by system | M | SD | Cut points | r |
|---|---|---|---|---|
| Cardiovascular regulation | .40** | |||
| Resting SBP (mm Hg) | 133.86 | 20.47 | ≥145.00 | |
| Resting DBP (mm Hg) | 79.11 | 11.75 | ≥86.00 | |
| Resting heart rate (beats per min) | 73.53 | 10.87 | ≥80.30 | |
| Lipid metabolism | .47** | |||
| BMI (kg/m2) | 32.47 | 7.84 | ≥37.38 | |
| Waist-to-hip circumference ratio | .89 | .09 | ≥.96 | |
| Serum triglycerides (mg/dL) | 111.04 | 66.77 | ≥132.00 | |
| HDL cholesterol (mg/dL) | 59.16 | 19.23 | ≤45.00 | |
| LDL cholesterol (mg/dL) | 101.20 | 35.54 | ≥121.36 | |
| Glucose metabolism | .56** | |||
| Blood glycated hemoglobin (HbA1c) | 6.14 | .64 | ≥6.49 | |
| Fasting blood glucose (mg/dL) | 101.27 | 15.43 | ≥107.00 | |
| Homeostasis model insulin resistance | 3.73 | 2.68 | ≥5.24 | |
| Inflammation | .54** | |||
| Serum C-reactive protein (mg/L) | 2.89 | 2.48 | ≥4.12 | |
| Serum IL6 (ng/mL) | 3.41 | 1.99 | ≥4.70 | |
| Fibrinogen (mg/dL) | 384.09 | 87.78 | ≥439.00 | |
| E-selectin (ng/mL) | 50.45 | 25.93 | ≥63.72 | |
| ICAM-1 (ng/mL) | 266.58 | 138.09 | ≥356.14 | |
| Sympathetic nervous system | .41** | |||
| Urine epinephrine (mg/g of creatine) | 1.59 | 1.08 | ≥1.86 | |
| Urine norepinephrine (mg/g of creatine) | 24.64 | 11.90 | ≥29.83 | |
| Parasympathetic nervous system | .48** | |||
| R–R interval standard deviation (ms) | 38.15 | 17.61 | ≤24.95 | |
| Root mean square successive differences (ms) | 27.39 | 16.01 | ≤16.32 | |
| Low-frequency spectral power (ms2) | 353.59 | 291.89 | ≤116.25 | |
| High-frequency spectral power (ms2) | 291.07 | 248.17 | ≤99.80 | |
| Hypothalamic-pituitary-adrenal axis | .29** | |||
| Urine cortisol (mg/g of creatine) | 10.31 | 8.18 | ≥14.00 | |
| Blood DHEA-S (μg/dL) | 99.66 | 68.47 | ≥137.00 | |
| AL | 1.91 | 1.01 |
Note. r = pairwise correlations between the system-level risk scores and allostatic load (AL) summary index and are based on pooled estimates from multiple imputation; SBP = systolic blood pressure; DBP = diastolic blood pressure; BMI = body mass index; HDL = high-density lipoprotein; LDL = low-density lipoprotein; IL6 = interleukin-6; ICAM-1 = intracelleular adhesion molecule-1; R–R = heartrate-to-heartrate; DHEA-S = dehydroepiandrosterone sulfate.
**
p <.01.