Table 1.
Baseline characteristics at blood draw by levels of vitamin D-related biomarkers among controls*
| Quartiles of 25-hydroxyvitamin D |
P for trend † |
Quartiles of vitamin D binding protein |
P for trend † |
Quartiles of parathyroid hormone |
P for trend † |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
|
|
|
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| 1 | 2 | 3 | 4 | 1 | 2 | 3 | 4 | 1 | 2 | 3 | 4 | ||||
| Range | 19.8–51.2 | 51.4–62.9 | 62.9–75.0 | 75.0–416.4 | 73.8–204.0 | 204.5–251.4 | 251.6–302.7 | 303.2–452.2 | 9.1–28.4 | 28.5–35.4 | 35.4–45.4 | 45.9–210.5 | |||
| Age (year)‡ | 62.1±7.3 | 63.9±8.1 | 63.4±7.5 | 62.2±7.8 | 0.90 | 66.1±7.3 | 64.4±7.9 | 64.6±6.9 | 61.9±8.4 | <0.001 | 60.3±7.8 | 63.3±7.2 | 64.2±7.3 | 63.8±7.9 | <0.001 |
| White (%) | 97.9 | 99.3 | 100 | 100 | 0.02 | 100 | 100 | 100 | 99 | 0.18 | 99.3 | 99.3 | 99.3 | 99.3 | 0.99 |
| Body mass index (kg/m2) | 26.0±4.8 | 25.3±4.5 | 25.6±4.9 | 24.5±3.4 | 0.006 | 26.9±5.3 | 25.5±4.9 | 24.5±3.9 | 24.8±3.3 | <0.001 | 24.6±4.3 | 24.9±4.7 | 25.8±4.6 | 26.2±4.1 | <0.001 |
| Physical activity (MET-hr/week) | 14.0±14.5 | 16.4±14.2 | 20.5±19.7 | 18.1±18.0 | 0.01 | 17.3±18.1 | 18.0±17.3 | 16.8±16.5 | 18.7±17.3 | 0.64 | 18.2±17.9 | 16.6±15.8 | 18.9±15.8 | 15.3±18.0 | 0.23 |
| Alternate Healthy Eating Index score | 36.5±8.9 | 39.0±9.2 | 39.5±8.1 | 39.4±8.1 | 0.004 | 40.1±8.5 | 39.8±8.9 | 35.9±8.3 | 38.0±7.4 | 0.01 | 38.8±8.5 | 38.7±8.1 | 39.1±9.1 | 37.9±8.9 | 0.39 |
| Dietary vitamin D intake (IU/day) | 194.5±105.1 | 200.4±89.2 | 228.0±97.3 | 253.3±115.5 | <0.001 | 217.7±101.8 | 227.0±105.9 | 221.7±97.7 | 213.9±119.9 | 0.74 | 220.7±102.9 | 227.3±96.1 | 220.9±114.2 | 207.4±104.6 | 0.18 |
| Dietary calcium intake (mg/day) | 673.9±189.3 | 711.0±195.8 | 747.2±238.2 | 767.7±222.0 | <0.001 | 752.4±214.6 | 728.8±203.7 | 712.0±227.7 | 688.9±199.9 | 0.03 | 751.8±215.3 | 732.3±208.9 | 716.8±230.9 | 699.5±201.5 | 0.03 |
| Alcohol (g/d) | 5.5±7.9 | 6.8±11.0 | 8.9±12.7 | 8.3±10.5 | 0.01 | 5.6±8.2 | 6.9±9.3 | 7.0±10.3 | 7.6±10.5 | 0.15 | 6.7±9.4 | 7.6±11.6 | 8.1±11.1 | 7.1±10.7 | 0.82 |
| Never smoker (%) | 32.2 | 38.2 | 34.0 | 43.1 | 0.11 | 40.4 | 29.0 | 41.0 | 37.4 | 0.89 | 31.5 | 39.6 | 36.8 | 39.6 | 0.23 |
| Past smoker (%) | 30.1 | 41.0 | 43.1 | 39.6 | 0.09 | 44.4 | 46.0 | 36.0 | 35.4 | 0.09 | 39.9 | 38.9 | 42.4 | 32.6 | 0.32 |
| Current smoker (%)‡ | |||||||||||||||
| 1–14 cigarettes/d | 18.2 | 6.3 | 9.7 | 9.0 | 0.04 | 7.1 | 10.0 | 10.0 | 15.2 | 0.08 | 10.5 | 9.7 | 9.0 | 13.9 | 0.41 |
| 15–24 cigarettes/d | 11.2 | 9.0 | 9.0 | 2.8 | 0.01 | 3.0 | 9.0 | 9.0 | 9.1 | 0.13 | 6.3 | 9.0 | 6.3 | 10.4 | 0.34 |
| ≥25 cigarettes/d | 8.4 | 5.6 | 4.2 | 4.9 | 0.17 | 5.1 | 6.0 | 4.0 | 3.0 | 0.39 | 11.2 | 2.8 | 5.6 | 3.5 | 0.02 |
| Hypertension (%) | 36.4 | 37.5 | 30.6 | 31.9 | 0.25 | 37.4 | 32.0 | 46.0 | 31.3 | 0.85 | 25.2 | 35.4 | 36.8 | 38.9 | 0.02 |
| Hypercholesterolemia (%) | 42.0 | 48.6 | 52.1 | 44.4 | 0.56 | 55.6 | 54.0 | 51.0 | 43.4 | 0.08 | 40.6 | 43.8 | 51.4 | 51.4 | 0.03 |
| Diabetes (%) | 6.3 | 7.6 | 5.6 | 6.3 | 0.81 | 6.1 | 7.0 | 3.0 | 6.1 | 0.69 | 8.4 | 6.3 | 8.3 | 2.8 | 0.11 |
| Parental MI before age 65 years (%) | 19.6 | 20.8 | 22.2 | 19.4 | 0.95 | 31.3 | 22.0 | 21.0 | 19.2 | 0.05 | 16.1 | 20.1 | 22.2 | 23.6 | 0.10 |
| Fasting status (%)‡ | 67.8 | 73.6 | 78.5 | 73.6 | 0.18 | 78.8 | 82.0 | 82.0 | 68.7 | 0.10 | 67.1 | 73.6 | 75.0 | 77.8 | 0.04 |
| Postmenopausal (%) | 90.9 | 91.0 | 92.4 | 88.9 | 0.66 | 93.9 | 93.0 | 93.0 | 90.9 | 0.44 | 83.9 | 91.7 | 93.1 | 94.4 | 0.002 |
| Postmenopausal hormone use (%)§ | 59.2 | 71.8 | 66.9 | 75.0 | 0.02 | 60.2 | 73.1 | 62.4 | 75.6 | 0.11 | 71.7 | 67.4 | 70.9 | 63.2 | 0.23 |
| Use of aspirin (%) | 49.7 | 54.9 | 54.2 | 61.1 | 0.07 | 40.4 | 46.0 | 49.0 | 51.5 | 0.11 | 57.3 | 59.7 | 50.0 | 52.8 | 0.21 |
| Use of multivitamin (%) | 32.6 | 52.1 | 49.6 | 52.2 | 0.003 | 51.1 | 54.6 | 40.0 | 45.9 | 0.19 | 52.6 | 39.4 | 46.3 | 48.2 | 0.76 |
| Biomarkers | |||||||||||||||
| 25-hydroxyvitamin D (nmol/L) | 41.3±7.8 | 57.5±3.5 | 68.6±3.5 | 89.8±29.9 | <0.001 | 58.1±14.8 | 63.3±13.6 | 65.9±41.5 | 68.8±19.3 | 0.003 | 69.8±19.7 | 65.9±17.8 | 62.3±17.0 | 59.9±34.5 | <0.001 |
| Vitamin D binding protein (mg/L) | 241.1±73.3 | 238.7±61.7 | 257.3±79.3 | 267.8±75.4 | 0.006 | 156.3±35.7 | 227.1±13.3 | 273.5±14.3 | 345.0±38.4 | <0.001 | 259.3±79.8 | 250.1±70.5 | 247.6±66.6 | 246.4±76.7 | 0.28 |
| Parathyroid hormone (pg/mL) | 43.1±16.9 | 39.3±19.2 | 37.3±12.4 | 34.5±11.7 | <0.001 | 39.2±15.1 | 39.0±13.2 | 41.3±22.1 | 35.8±12.7 | 0.27 | 24.0±3.5 | 31.8±2.1 | 40.1±2.8 | 58.3±17.5 | <0.001 |
| Total cholesterol (mg/dL) | 232.1±38.1 | 223.6±37.4 | 227.6±47.1 | 221.5±32.3 | 0.05 | 230.7±44.6 | 228.2±43.9 | 228.4±31.4 | 222.9±42.0 | 0.19 | 216.7±37.8 | 229.1±36.7 | 228.2±45.6 | 230.6±34.7 | 0.01 |
| LDL cholesterol (mg/dL) | 135.8±34.9 | 127.6±33.6 | 132.7±36.4 | 128.0±34.6 | 0.14 | 129.8±36.7 | 138.7±37.6 | 132.8±35.8 | 126.3±34.5 | 0.35 | 120.9±32.8 | 131.9±37.0 | 132.8±35.8 | 138.4±32.1 | <0.001 |
| HDL cholesterol (mg/dL) | 58.5±15.9 | 62.4±18.6 | 59.2±17.7 | 63.9±19.5 | 0.04 | 58.7±15.5 | 57.4±14.6 | 63.8±21.4 | 64.4±18.3 | 0.005 | 62.1±17.9 | 62.6±19.0 | 60.8±17.7 | 58.5±17.6 | 0.05 |
| Triglycerides (mg/dL) | 135.5±101.9 | 115.2±72.3 | 125.7±68.7 | 114.1±55.9 | 0.05 | 116.0±77.8 | 116.2±56.1 | 120.7±89.7 | 128.1±69.6 | 0.22 | 115.5±62.4 | 117.8±59.1 | 128.0±92.8 | 129.1±86.9 | 0.09 |
| High-sensitivity C-reactive protein (mg/dL) | 0.40±0.55 | 0.36±0.42 | 0.39±0.44 | 0.30±0.34 | 0.10 | 0.36±0.42 | 0.28±0.26 | 0.28±0.33 | 0.39±0.41 | 0.61 | 0.37±0.56 | 0.32±0.38 | 0.39±0.45 | 0.37±0.37 | 0.67 |
| Creatinine (mg/dL) | 0.73±0.15 | 0.74±0.16 | 0.74±0.15 | 0.76±0.18 | 0.10 | 0.73±0.13 | 0.79±0.21 | 0.74±0.19 | 0.74±0.14 | 0.92 | 0.71±0.12 | 0.73±0.16 | 0.75±0.14 | 0.77±0.21 | 0.002 |
| Albumin (g/dL) | 4.6±0.31 | 4.5±0.33 | 4.6±0.31 | 4.6±0.30 | 0.37 | 4.5±0.26 | 4.5±0.27 | 4.5±0.30 | 4.6±0.32 | 0.15 | 4.6±0.30 | 4.5±0.29 | 4.5±0.32 | 4.6±0.35 | 0.58 |
| Hemoglobin A1c (%) | 5.7±0.63 | 5.6±0.51 | 5.7±0.41 | 5.6±0.58 | 0.35 | 5.7±0.69 | 5.6±0.40 | 5.6±0.42 | 5.6±0.49 | 0.10 | 5.6±0.56 | 5.6±0.51 | 5.7±0.60 | 5.7±0.47 | 0.63 |
*
Values are mean±SD for continuous variables or % for categorical variables.
N=575 for 25-hydroxyvitamin D and parathyroid hormone and N=398 for vitamin D binding protein.
†
P for trend was assessed by F test and modeling median values in each quartiles continuously for variables expressed as mean±SD or Cochran-Armitage trend test for variables expressed as percentages.
‡
Matching factors.
§
Among postmenopausal women only.