Table 1 Characteristics of participants according to quartiles of serum magnesium.
Variables | All participants | Serum magnesium (mmol/L) | p value | |||
|---|---|---|---|---|---|---|
Quartile 1 ≤ 0.55 | Quartile 2 0.551–0.85 | Quartile 3 0.851–1.15 | Quartile 4 > 1.15 | |||
No. of participants (%) | 1257 (100) | 74 (5.9) | 493 (39.2) | 492 (39.1) | 198 (15.8) | |
Median of serum magnesium (quartile range, mmol/L) | 0.89 (0.73–1.06) | 0.50 (0.47–0.52) | 0.73 (0.67–0.79) | 0.98 (0.91–1.05) | 1.26 (1.19–1.39) | |
Age (years) | 42.5 ± 15.2 | 46.0 ± 20.1 | 39.0 ± 14.6 | 43.5 ± 14.7 | 47.7 ± 13.4 | 0.000 |
Age group, % | ||||||
Young (18–39 years) | 48.0 | 48.6 | 58.8 | 43.5 | 31.8 | 0.000 |
Middle-aged (40–64 years) | 42.5 | 28.4 | 33.7 | 47.2 | 58.6 | |
Elderly (≥65 years) | 9.5 | 23.0 | 7.5 | 9.3 | 9.6 | |
Sex (%) | ||||||
Male | 49.2 | 44.6 | 60.9 | 56.1 | 33.8 | 0.000 |
Female | 50.8 | 55.4 | 39.1 | 43.9 | 66.2 | |
Income (×1000 RMB/year, %) | ||||||
<10 | 4.5 | 14.9 | 4.5 | 4.3 | 1.0 | 0.000 |
10–50 | 49.6 | 56.8 | 54.2 | 47.0 | 42.4 | |
50–100 | 32.0 | 23.0 | 28.6 | 32.5 | 42.4 | |
≥100 | 13.9 | 5.4 | 12.8 | 16.3 | 14.1 | |
Smoking status (%) | ||||||
Never | 71.0 | 75.7 | 64.2 | 74.6 | 77.3 | 0.004 |
Occasionally | 1.5 | 0.0 | 1.8 | 1.4 | 1.0 | |
Frequently | 27.5 | 24.3 | 33.9 | 24.0 | 21.7 | |
BMI (kg/m2) | 24.7 ± 3.7 | 25.0 ± 4.6 | 24.4 ± 3.7 | 24.7 ± 3.7 | 25.1 ± 3.6 | 0.183 |
BMI (kg/m2) constitution, % | ||||||
<18.5 (marasmus) | 3.3 | 4.1 | 3.2 | 3.3 | 3.5 | 0.379 |
18.5–23.9 (moderate) | 42.7 | 44.6 | 44.8 | 41.1 | 40.5 | |
24–26.9 (overweight) | 28.9 | 21.6 | 29.6 | 30.7 | 24.7 | |
≥27 (obese) | 25.1 | 29.7 | 22.3 | 25.0 | 31.3 | |
Education | ||||||
Junior school or below | 18.1 | 32.4 | 18.7 | 18.5 | 10.6 | 0.000 |
High school | 54.2 | 56.8 | 58.6 | 50.4 | 52.0 | |
Junior college or a bove | 27.7 | 10.8 | 22.7 | 31.1 | 37.4 | |
