Table 2 Comparison of baseline characteristics between participants and non-participants of clinical follow-up surveys
| Â | Â | Clinical follow-up surveys | |||||
|---|---|---|---|---|---|---|---|
Participants of baseline survey | Participants | Non-participants | p-value for difference | ||||
N | Average value | N | Average value | N | Average value | ||
Baseline characteristics | |||||||
 Age (years) | 2012 | 73.0 ± 5.2 | 1556 | 72.4±4.9 | 456 | 75.1±5.8 | <0.001 |
 Height (cm) | 2012 | 162.8 ± 5.7 | 1556 | 163.0±5.8 | 456 | 162.3±5.5 | 0.026 |
 Weight (kg) | 2012 | 60.9 ± 8.6 | 1556 | 61.2±8.4 | 456 | 59.8±9.1 | 0.004 |
 BMI (kg/m2) | 2012 | 22.9 ± 2.8 | 1556 | 23.0±2.7 | 456 | 22.7±3.1 | 0.042 |
 Waist circumference (cm) | 2012 | 85.5 ± 7.9 | 1552 | 85.6±7.7 | 460 | 85.3±8.7 | 0.452 |
 Physical activity (Mets·min/day) | 1848 | 181×/÷2.7 | 1443 | 184×/÷2.8 | 405 | 169×/÷2.6 | 0.129 |
 Energy intake (kcal/day) | 1689 | 2047±354 | 1338 | 2067±348 | 351 | 1971±367 | <0.001 |
 Calcium intake (mg/day) | 1689 | 514±190 | 1338 | 523±190 | 351 | 479±185 | <0.001 |
 Vitamin D intake (mg/day) | 1689 | 9.7±6.0 | 1338 | 9.6±6.0 | 351 | 10.2±6.1 | 0.099 |
 Vitamin K intake (mg/day) | 1689 | 207±111 | 1338 | 212±111 | 351 | 187±109 | <0.001 |
 LS-BMD (g/cm2) | 1914 | 1.026±0.191 | 1493 | 1.028±0.189 | 421 | 1.018±0.198 | 0.347 |
 TH-BMD (g/cm2) | 2006 | 0.878±0.126 | 1552 | 0.885±0.125 | 454 | 0.857±0.128 | <0.001 |
 FN-BMD (g/cm2) | 2006 | 0.740±0.115 | 1552 | 0.746±0.114 | 454 | 0.721±0.117 | <0.001 |
 PTH (pg/ml) | 1828 | 20.4×/÷1.6 | 1427 | 20.4×/÷1.5 | 401 | 20.2×/÷1.6 | 0.678 |
 OC (ng/ml) | 1963 | 4.90×/÷1.5 | 1519 | 4.92×/÷1.5 | 444 | 4.82×/÷1.5 | 0.334 |
 P1NP (mg/l) | 1417 | 34.7×/÷1.5 | 1119 | 34.5×/÷1.5 | 298 | 35.4×/÷1.5 | 0.359 |
 TRACP5b (mU/dl) | 2003 | 212.3×/÷1.7 | 1549 | 209.2×/÷1.7 | 454 | 223.1×/÷1.8 | 0.031 |
 CTX (ng/ml) | 1545 | 0.205×/÷1.6 | 1213 | 0.20×/÷1.6 | 332 | 0.21×/÷1.7 | 0.315 |
 ucOC (ng/ml) | 1970 | 2.89×/÷1.9 | 1526 | 2.87×/÷1.8 | 444 | 2.95×/÷2.0 | 0.487 |
 FPG (mg/dl) | 2008 | 104.2±31.4 | 1553 | 102.6±27.1 | 455 | 109.6±42.5 | <0.001 |
 HbA1c (%) | 2010 | 5.7±0.8 | 1555 | 5.7±0.7 | 455 | 5.8±0.9 | 0.002 |
 Insulin (mU/l) a | 1957 | 4.9×/÷2.1 | 1513 | 4.8×/÷2.0 | 444 | 5.3×/÷2.3 | 0.036 |
 Homa-IR b | 1810 | 1.1×/÷2.0 | 1411 | 1.1×/÷2.0 | 399 | 1.1×/÷2.1 | 0.328 |
 Albumin (mg/dl) | 2012 | 4.5±0.3 | 1556 | 4.6±0.3 | 456 | 4.5±0.3 | <0.001 |
 Total protein (mg/dl) | 2012 | 7.3±0.5 | 1556 | 7.3±0.5 | 456 | 7.3±0.5 | 0.927 |
 AST (mg/dl) | 2012 | 25.8×/÷1.4 | 1556 | 25.5×/÷1.3 | 456 | 26.9×/÷1.4 | 0.002 |
 ALT (mg/dl) | 2012 | 20.1×/÷1.6 | 1556 | 20.2×/÷1.5 | 456 | 19.9×/÷1.6 | 0.627 |
 Triglyceride (mg/dl) | 2012 | 114.3×/÷1.6 | 1556 | 115.3×/÷1.6 | 456 | 110.8×/÷1.6 | 0.117 |
 LDL (mg/dl) | 2012 | 118.9×/÷1.3 | 1556 | 120.2×/÷1.3 | 456 | 114.7×/÷1.3 | <0.001 |
 HDL (mg/dl) | 2012 | 53.8×/÷1.3 | 1556 | 54.1×/÷1.3 | 456 | 53.0×/÷1.3 | 0.169 |
 Creatinine (mg/dl) | 2012 | 0.87×/÷1.2 | 1556 | 0.87×/÷1.2 | 456 | 0.89×/÷1.3 | 0.134 |
 eGFR (mL/min/1.73 m2) | 2012 | 65.6×/÷1.2 | 1556 | 66.1×/÷1.2 | 456 | 64.2×/÷1.3 | 0.022 |
 Cystatin-C (mg/l) | 1834 | 0.85×/÷1.2 | 1433 | 0.83×/÷1.2 | 401 | 0.89×/÷1.3 | <0.001 |
 hsCRP (ng/ml) | 2006 | 648.0×/÷3.2 | 1553 | 621.6×/÷3.2 | 453 | 747.1×/÷3.2 | 0.003 |
 Uric acid (mg/dl) | 2012 | 5.7×/÷1.3 | 1556 | 5.7×/÷1.3 | 456 | 5.7×/÷1.3 | 0.474 |
History or present situation (N, %) | |||||||
 Current smoker | 2012 | 340, 16.9% | 1556 | 240, 15.4% | 456 | 100, 22.0% | 0.001 |
 Habitual drinker | 2012 | 956, 47.5% | 1556 | 775, 49.8% | 456 | 181, 39.8% | <0.001 |
 Gastrectomy | 2012 | 136, 6.8% | 1556 | 103, 6.6% | 456 | 33, 7.3% | 0.714 |
 Prostate cancer | 2012 | 32, 1.6% | 1556 | 23, 1.5% | 456 | 9, 2.0% | 0.592 |
 Asthma | 2012 | 12, 0.6% | 1556 | 10, 0.6% | 456 | 2, 0.4% | 0.882 |
 Connective tissue diseases | 2012 | 15, 0.7% | 1556 | 12, 0.8% | 456 | 3, 0.7% | 0.805 |
 Glucocorticoid therapy | 2012 | 27, 1.3% | 1556 | 22, 1.4% | 456 | 5, 1.1% | 0.778 |
 Hyperthyroidism | 2012 | 1, 0.05% | 1556 | 1, 0.06% | 456 | 0, 0% | 1.000 |
 Parathyroid diseases | 2012 | 1, 0.05% | 1556 | 1, 0.06% | 456 | 0, 0% | 1.000 |
 Type 1 diabetes mellitus | 2012 | 4, 0.2% | 1556 | 4, 0.3% | 456 | 0, 0% | 0.628 |
 Type 2 diabetes mellitus | 2012 | 364, 18.1% | 1556 | 266, 17.1% | 456 | 98, 21.5% | 0.036 |