Table 1.
Clinical characteristics of the participants in NHANES 2003–2006 according to HbAA quartiles
| Variables | Total (n = 3234) | HbAA quartiles | ||||
|---|---|---|---|---|---|---|
| Q1 | Q2 | Q3 | Q4 | P | ||
| Age, year | 49.75 ± 0.55 | 52.26 ± 0.88 | 50.94 ± 0.80 | 49.48 ± 0.75 | 46.64 ± 0.63 | < 0.001 |
| Male, % | 49.6 (1.0) | 45.4 (2.0) | 44.1 (2.2) | 47.8 (2.2) | 60.2 (1.6) | < 0.001 |
| Race/ethnicity, % | < 0.001 | |||||
| Non-Hispanic White | 70.0 (2.1) | 73.0 (2.6) | 68.9 (2.1) | 72.0 (2.8) | 70.0 (2.1) | |
| Non-Hispanic Black | 11.3 (1.2) | 10.1 (1.2) | 11.1 (1.5) | 13.6 (1.6) | 11.3 (1.2) | |
| Mexican American | 7.8 (1.0) | 8.9 (1.4) | 9.6 (1.1) | 6.4 (1.3) | 7.8 (1.0) | |
| Others | 11.0 (0.8) | 8.0 (1.2) | 10.4 (1.4) | 8.0 (1.1) | 11.0 (0.8) | |
| Smokers, % | 20.9 (1.2) | 5.4 (1.1) | 6.2 (1.4) | 7.0 (1.0) | 62.2 (2.2) | < 0.001 |
| Marriage, % | 63.9 (1.1) | 67.8 (1.7) | 67.3 (2.8) | 67.8 (2.1) | 53.6 (1.8) | < 0.001 |
| Education levels, % | < 0.001 | |||||
| Under high school | 17.1 (1.1) | 17.6 (1.5) | 14.5 (1.5) | 15.1 (1.7) | 21.0 (2.0) | |
| High school | 25.0 (1.1) | 23.4 (2.2) | 22.4 (2.2) | 23.2 (1.8) | 30.5 (1.9) | |
| Above high school | 58.0 (1.5) | 59.0 (1.8) | 63.1 (2.4) | 61.6 (2.3) | 48.6 (2.7) | |
| Family PIR | 3.07 ± 0.04 | 2.96 ± 0.06 | 3.15 ± 0.06 | 3.31 ± 0.06 | 2.86 ± 0.06 | < 0.001 |
| Body mass index, kg/m2 | 29.09 ± 0.16 | 29.61 ± 0.22 | 29.64 ± 0.30 | 28.72 ± 0.35 | 28.46 ± 0.30 | 0.036 |
| Systolic blood pressure, mmHg | 123.23 ± 0.47 | 125.15 ± 0.81 | 123.6 ± 0.85 | 122.34 ± 1.11 | 122.07 ± 0.74 | 0.059 |
| Diastolic blood pressure, mmHg | 70.08 ± 0.32 | 70.41 ± 0.90 | 69.88 ± 0.53 | 70.27 ± 0.52 | 69.81 ± 0.60 | 0.846 |
| Albumin, g/L | 42.25 ± 0.10 | 42.23 ± 0.17 | 42.14 ± 0.15 | 42.34 ± 0.13 | 42.27 ± 0.15 | 0.708 |
| Alanine aminotransferase, U/L | 25.26 ± 0.54 | 24.97 ± 1.42 | 24.92 ± 0.68 | 26.37 ± 0.54 | 24.78 ± 0.48 | 0.151 |
| γ-Glutamyl transpeptidase, U/L | 25.64 ± 0.54 | 26.58 ± 1.11 | 24.73 ± 1.11 | 25.02 ± 1.06 | 26.29 ± 1.16 | 0.420 |
| Fasting triglyceride, mg/dl | 139.79 ± 2.60 | 144.28 ± 5.49 | 144.94 ± 5.71 | 124.59 ± 4.06 | 145.45 ± 6.16 | 0.008 |
| Total cholesterol, mmol/L | 5.15 ± 0.03 | 5.14 ± 0.05 | 5.19 ± 0.06 | 5.14 ± 0.04 | 5.14 ± 0.05 | 0.883 |
| HDL-C, mmol/L | 1.40 ± 0.01 | 1.39 ± 0.02 | 1.42 ± 0.02 | 1.47 ± 0.02 | 1.31 ± 0.02 | < 0.001 |
| LDL-C, mmol/L | 3.00 ± 0.02 | 2.94 ± 0.03 | 3.00 ± 0.04 | 2.99 ± 0.04 | 3.06 ± 0.04 | 0.165 |
| Platelet count, 1000 cells/μL | 259.26 ± 1.86 | 252.75 ± 2.67 | 258.53 ± 4.10 | 259.82 ± 2.46 | 265.19 ± 3.12 | 0.047 |
| Fasting blood glucose, mmol/L | 5.82 ± 0.04 | 5.98 ± 0.05 | 5.88 ± 0.08 | 5.68 ± 0.05 | 5.77 ± 0.08 | 0.002 |
| Total energy intake, kcal | 2150.57 ± 20.29 | 2001.84 ± 29.72 | 2111.09 ± 48.95 | 2165.01 ± 27.59 | 2305.21 ± 41.17 | < 0.001 |
| Total fat intake, gm | 84.14 ± 0.84 | 78.44 ± 1.42 | 82.01 ± 2.06 | 85.92 ± 1.85 | 89.45 ± 1.9 | < 0.001 |
| HbGA/HbAA | 0.95 ± 0.02 | 1.04 ± 0.05 | 0.98 ± 0.02 | 0.95 ± 0.02 | 0.82 ± 0.02 | < 0.001 |
| USFLI | 24.04 ± 0.46 | 26.61 ± 0.76 | 25.89 ± 1.03 | 21.52 ± 1.03 | 22.4 ± 0.83 | 0.002 |
| NAFLD, % | 30.8 (1.0) | 34.7 (1.8) | 34.0 (2.2) | 25.4 (1.8) | 29.5 (1.8) | 0.001 |
| Subgroup, NAFLD prevalence | ||||||
| BMI | ||||||
| < 30 kg/m2 | 13.1 (0.8) | 14.5 (1.9) | 15.5 (1.9) | 9.8 (1.1) | 13.0 (1.4) | 0.056 |
| ≥ 30 kg/m2 | 61.8 (1.7) | 65.4 (2.5) | 61.5 (3.7) | 57.4 (3.1) | 62.4 (3.7) | 0.408 |
| ALT | ||||||
| ≤ 40 U/L | 26.9 (1.0) | 29.9 (2.0) | 29.7 (2.2) | 20.7 (1.7) | 27.2 (1.8) | 0.002 |
| > 40 U/L | 69.1 (2.6) | 81.4 (5.1) | 75.0 (6.0) | 63.6 (5.6) | 56.4 (6.9) | 0.016 |
Participants were classified into quartiles according to HbAA levels: Q1, HbAA ≤ 36.10 pmol/g Hb; Q2, 36.10 < HbAA ≤ 47.60 pmol/g Hb; Q3, 47.60 < HbAA ≤ 66.50 pmol/g Hb; and Q4, HbAA > 66.50 pmol/g Hb
Continuous variables were presented as the weighted mean ± SE and compared by Survey regression models
Categorical variables were presented as weighted percent (SE) and compared by using the Rao–Scott χ2 test