Table 1.
Characteristics of the study population by bone mineral density quartiles in the National Health and Nutrition Examination Survey 2011–2018
| Characteristic | Total bone mineral density | ||||
|---|---|---|---|---|---|
| Q1 ≤ 1.03 |
Q2 1.04–1.10 |
Q3 1.11–1.17 |
Q4 ≥ 1.18 |
P-value | |
| No | 2806 | 2805 | 2798 | 2818 | |
| Gender, n (%) | < 0.001 | ||||
| Male | 920 (32.79) | 1253 (44.67) | 1551 (55.43) | 1998 (70.90) | |
| Female | 1886 (67.21) | 1552 (55.33) | 1247 (44.57) | 820 (29.10) | |
| Age (mean ± SD, year) | 38.93 ± 13.45 | 36.66 ± 12.24 | 36.62 ± 11.70 | 36.72 ± 11.76 | < 0.001 |
| Race, n (%) | < 0.001 | ||||
| Mexican American | 538 (19.17) | 437 (15.58) | 463 (16.55) | 301 (10.68) | |
| Non-Hispanic White | 888 (31.65) | 1012 (36.08) | 972 (34.74) | 842 (29.88) | |
| Non-Hispanic Black | 278 (9.91) | 427 (15.22) | 607 (21.69) | 1090 (38.68) | |
| Other Race | 1102 (39.27) | 929 (33.12) | 756 (27.02) | 585 (20.76) | |
| Marital status, n (%) | < 0.001 | ||||
| Married/ cohabiting | 1560 (55.60) | 1591 (56.72) | 1543 (55.15) | 1470 (52.16) | |
| Widowed/divorced/separated | 412 (14.68) | 322 (11.48) | 319 (11.40) | 327 (11.60) | |
| Never married | 552 (19.67) | 664 (23.67) | 719 (25.70) | 795 (28.21) | |
| Unclear | 282 (10.05) | 228 (8.13) | 217 (7.76) | 226 (8.02) | |
| Education, n (%) | < 0.001 | ||||
| Under high school | 538 (19.17) | 476 (16.97) | 481 (17.19) | 408 (14.48) | |
| High school or equivalent | 545 (19.42) | 526 (18.75) | 582 (20.80) | 585 (20.76) | |
| Above high school | 1441 (51.35) | 1574 (56.11) | 1518 (54.25) | 1599 (56.74) | |
| Unclear | 282 (10.05) | 229 (8.16) | 217 (7.76) | 226 (8.02) | |
| PIR, n (%) | 0.042 | ||||
| ≤ 1.26 | 813 (28.97) | 730 (26.02) | 748 (26.73) | 704 (24.98) | |
| 1.27–3.24 | 822 (29.29) | 831 (29.63) | 851 (30.41) | 836 (29.67) | |
| ≥ 3.25 | 936 (33.36) | 1001 (35.69) | 962 (34.38) | 1052 (37.33) | |
| Unclear | 235 (8.37) | 243 (8.66) | 237 (8.47) | 226 (8.02) | |
| BMI (mean ± SD, kg/m 2 ) | 26.87 ± 6.40 | 28.18 ± 6.72 | 28.99 ± 6.84 | 29.79 ± 6.63 | < 0.001 |
| Activity, n (%) | < 0.001 | ||||
| Active | 1716 (61.15) | 1555 (55.44) | 1466 (52.39) | 1430 (50.75) | |
| Less active | 171 (6.09) | 197 (7.02) | 228 (8.15) | 204 (7.24) | |
| Inactive | 913 (32.54) | 1044 (37.22) | 1097 (39.21) | 1177 (41.77) | |
| Unclear | 6 (0.21) | 9 (0.32) | 7 (0.25) | 7 (0.25) | |
| MET scores (median, IQR) | 120.00 (60.00-257.50) | 130.00 (60.00-300.00) | 150.00 (60.00-360.00) | 180.00 (80.00-360.00) | < 0.001 |
| Smoking, n (%) | < 0.001 | ||||
| Never | 898 (32.00) | 946 (33.73) | 808 (28.88) | 861 (30.55) | |
| Former | 196 (6.99) | 196 (6.99) | 232 (8.29) | 232 (8.23) | |
| Current | 270 (9.62) | 288 (10.27) | 335 (11.97) | 324 (11.50) | |
| Unclear | 1442 (51.39) | 1375 (49.02) | 1423 (50.86) | 1401 (49.72) | |
| Alcohol, n (%) | < 0.001 | ||||
| Yes | 1675 (59.69) | 1860 (66.31) | 1975 (70.59) | 2071 (73.49) | |
| No | 37 (1.32) | 42 (1.50) | 64 (2.29) | 44 (1.56) | |
| Unclear | 1094 (38.99) | 903 (32.19) | 759 (27.13) | 703 (24.95) | |
| Hypertension, n (%) | < 0.001 | ||||
| Yes | 650 (23.16) | 591 (21.07) | 666 (23.80) | 815 (28.92) | |
| No | 2156 (76.84) | 2214 (78.93) | 2132 (76.20) | 2003 (71.08) | |
| Diabetes, n (%) | 0.045 | ||||
| Yes | 270 (9.62) | 278 (9.91) | 265 (9.47) | 324 (11.50) | |
| No | 2536 (90.38) | 2527 (90.09) | 2533 (90.53) | 2494 (88.50) | |
| Thyroid disease, n (%) | < 0.001 | ||||
| Yes | 235 (8.37) | 168 (5.99) | 143 (5.11) | 108 (3.83) | |
| No | 2284 (81.40) | 2401 (85.60) | 2435 (87.03) | 2481 (88.04) | |
| Unclear | 287 (10.23) | 236 (8.41) | 220 (7.86) | 229 (8.13) | |
| Vitamin D intake (median (IQR), mcg) | 3.00 (1.45–5.45) | 3.25 (1.55–5.80) | 3.25 (1.55–5.80) | 3.50 (1.65–6.30) | 0.002 |
| Vitamin D supplements (median (IQR), (mcg) | 25.00 (10.00–35.00) | 25.00 (10.00–35.00) | 20.00 (10.05-30.00) | 20.00 (10.00-26.48) | 0.736 |
| Calcium intake (median (IQR), mg) | 792.50 (536.50-1087.25) | 834.50 (570.50-1156.25) | 876.50 (612.00-1226.75) | 921.25 (636.50-1274.50) | < 0.001 |
| Calcium supplements (median (IQR), mg) | 333.00 (200.00-535.00) | 220.00 (200.00-500.00) | 220.00 (200.00-500.00) | 210.00 (200.00-500.00) | < 0.001 |
| Vitamin D (mean ± SD, nmol/L) | 60.85 ± 26.00 | 59.97 ± 24.29 | 59.62 ± 24.26 | 58.70 ± 24.31 | 0.015 |
| Total calcium (mean ± SD, mg/dL) | 9.37 ± 0.37 | 9.37 ± 0.34 | 9.37 ± 0.34 | 9.40 ± 0.35 | 0.006 |
| ALT (median (IQR), U/L) | 20.00 (15.00–28.00) | 20.00 (15.00–28.00) | 21.00 (16.00–30.00) | 21.00 (16.00–30.00) | 0.026 |
| Total Cholesterol (mean ± SD, mg/dL) | 191.63 ± 39.68 | 188.38 ± 41.21 | 187.19 ± 39.61 | 185.22 ± 41.59 | < 0.001 |
| Serum uric acid (mean ± SD, mg/dL) | 5.00 ± 1.30 | 5.21 ± 1.34 | 5.41 ± 1.39 | 5.67 ± 1.39 | < 0.001 |
| Visceral fat mass (median (IQR),kg) | 0.44 (0.26–0.66) | 0.42 (0.26–0.62) | 0.43 (0.27–0.62) | 0.40 (0.25–0.59) | < 0.001 |
| Lean body mass (mean ± SD,kg) | 44.10 ± 10.40 | 49.30 ± 11.35 | 53.22 ± 11.58 | 59.67 ± 12.16 | < 0.001 |
| Log LM/VFM | 2.00 (1.85–2.19) | 2.06 (1.91–2.25) | 2.09 (1.94–2.28) | 2.17 (2.02–2.35) | < 0.001 |
| Total BMD (mean ± SD,g/cm 2 ) | 0.98 ± 0.05 | 1.08 ± 0.02 | 1.14 ± 0.02 | 1.26 ± 0.06 | < 0.001 |
Abbreviations:
BMD bone mineral density, SD standard deviation, IQR interquartile range, PIR ratio of family income to poverty, BMI body mass index, ALT alanine aminotransferase, LM/VFM lean body mass/ visceral fat mass, MET metabolic equivalent